A mechanically responsive piezoelectric material, a method for preparing the same, a method and device for remediating farmland pollution in combination with agricultural organic waste

Abstract

The application belongs to the technical field of soil pollution remediation environmental engineering, and discloses a mechanical response type piezoelectric material, a preparation method thereof, a method and a device for remediation of farmland pollution in combination with agricultural organic waste, the mechanical response type piezoelectric material comprises a core and a shell coated on the core, the core is obtained by mixing and granulating first raw materials, the first raw materials include first hydroxyl aluminum pillared fluorophlogopite, peroxodisulfate and a first inorganic binder; the shell is formed by a coating slurry, the coating slurry includes a piezoelectric catalytic material, second hydroxyl aluminum pillared fluorophlogopite, water and a second inorganic binder; the piezoelectric catalytic material is a defect type cerium modified lutetium, iron co-doped bismuth calcium niobate. The application organically integrates piezoelectric catalysis, oxidant slow release and biological stabilization, and constructs a new system for continuous treatment of farmland composite pollution, which takes mechanical disturbance as driving force, takes core-shell composite material as core, and connects physical and chemical remediation and biological remediation.

Description

Technical Field

[0001] This application belongs to the field of environmental engineering technology for soil pollution remediation, and specifically relates to a mechanically responsive piezoelectric material, its preparation method, and a method and apparatus for remediating farmland pollution using agricultural organic waste. Background Technology

[0002] Soil pollution is the phenomenon of soil quality decline caused by the introduction of harmful substances into the environment through human activities. It poses a wide-ranging and profound threat to ecosystems and human health. Polluted soil can not only cause secondary pollution of groundwater and damage the original ecological structure of the soil, but also enter the food chain through pathways such as crop bioaccumulation, ultimately affecting the quality of agricultural products and human health. Therefore, how to effectively reduce the concentration of pollutants in the soil, alleviate environmental pressure, and gradually restore the natural ecological functions of the soil has always been an important issue that urgently needs to be addressed in the field of environmental engineering.

[0003] Currently, remediation technologies for organically contaminated soils at industrial sites can be broadly categorized into three types: physical remediation, chemical remediation, and bioremediation. Physical remediation technologies, such as soil replacement, deep tillage, and thermal desorption, are relatively simple to operate and suitable for large-scale pollution treatment, but generally suffer from high treatment costs. Some processes may also cause secondary pollution due to pollutant migration or volatilization. Chemical remediation technologies, such as oxidation-reduction, precipitation, and leaching, are capable of treating various pollutants and are relatively quick to take effect. However, they also face challenges such as high reagent costs and the potential for secondary pollution from byproducts. For example, the traditional iron-based activated persulfate advanced oxidation system easily generates large amounts of iron sludge that clogs soil pores and causes soil acidification during the reaction. Bioremediation technologies, including microbial remediation, phytoremediation, and animal remediation, offer advantages such as environmental friendliness, no secondary pollution, and contribution to soil ecological restoration. However, their remediation cycles are generally long, and their treatment effectiveness is highly dependent on environmental conditions such as temperature, moisture content, and oxygen content, resulting in insufficient stability in practical engineering applications.

[0004] Piezoelectric catalysis is an emerging catalytic technology that combines the piezoelectric effect with catalysis. With its high efficiency, environmental friendliness, sustainability, low operating costs, and ease of operation, it has shown promising application prospects in water pollution treatment and air purification. However, research on piezoelectric catalysis technology in soil remediation is still relatively rare, and its application in practical engineering scenarios is even more scarce. This is due to two main reasons. First, it is difficult to achieve uniform, stable, and continuous mechanical energy input at the soil remediation site. The heterogeneity of the soil system causes the mechanical force to decay rapidly during transmission. Piezoelectric catalytic materials buried deep within the soil often cannot obtain sufficient deformation to generate piezoelectric polarization charges, severely limiting the efficiency of piezoelectric catalysis. Second, soil pollutants are diverse and have varying properties. Some hydrophobic or strongly adsorbed organic pollutants are difficult to effectively contact the active sites of piezoelectric catalytic materials. Furthermore, the charge carriers generated by piezoelectric catalysis have short lifetimes and are prone to recombination. Without effective interfacial charge extraction and oxidant activation mechanisms, relying solely on the piezoelectric material itself is often insufficient to achieve efficient degradation of organic pollutants in the soil. Furthermore, if the oxidant is simply mixed and added with the piezoelectric catalytic material, the oxidant will quickly diffuse and be lost in the soil pore water. This not only makes it impossible to maintain a stable concentration near the catalytic site, but also easily leads to waste of the reagent and soil residue, further limiting the engineering application of piezoelectric catalytic technology in soil remediation. Summary of the Invention

[0005] This application aims to improve at least one technical problem in the background art.

[0006] The first aspect of this application provides a mechanically responsive piezoelectric material, including a core and a shell covering the core, wherein the core is obtained by mixing and granulating a first raw material, the first raw material including a first aluminum hydroxyl pillared fluorophlogopite, persulfate and a first inorganic binder; The outer shell is formed by a coating slurry, which includes a piezoelectric catalytic material, a second hydroxyl aluminum-pillared fluorophlogopite, water, and a second inorganic binder. The piezoelectric catalyst is lutetium-iron co-doped calcium niobate modified with defective cerium oxide, with the general chemical formula Ca. 1-α Lu α Bi2Nb 2-β Fe β O 9-δ @CeO 2-x Where 0.05≤α≤0.3, 0.05≤β≤0.3, and β≥α / 2; 0.01≤δ≤0.275, and δ=β-α / 2; 0.02≤x≤0.35; Both the first hydroxyl aluminum-pillared fluorophlogopite and the second hydroxyl aluminum-pillared fluorophlogopite were obtained by modifying fluorophlogopite with hydroxyl aluminum-pillared liquid.

[0007] In some embodiments, the defective cerium oxide is loaded onto the surface of the lutetium-iron co-doped bismuth niobate calcium niobate at an amount of 0.5%-15% of the mass of the lutetium-iron co-doped bismuth niobate calcium niobate.

[0008] In some embodiments, the aluminum hydroxyl pillared liquid is prepared by reacting an aluminum salt solution with an alkaline solution, wherein the alkaline solution contains OH... - With Al in the aluminum salt solution 3+ The molar ratio is 1:(1.5-2.8); The aluminum salt is at least one of aluminum chloride, aluminum nitrate, aluminum sulfate, and aluminum isopropoxide; The alkaline solution is at least one of sodium hydroxide, potassium hydroxide, ammonia, and sodium carbonate; The fluorophlogopite and the aluminum hydroxide pillar solution contain Al 3+ The mass ratio is 1:(0.02-0.50).

[0009] In some embodiments, the mass ratio of the first aluminum hydroxyl pillared fluorophlogopite, the persulfate, and the first inorganic binder is (35-75):(10-45):(1-15).

[0010] In some embodiments, the mass ratio of the piezoelectric catalytic material, the second aluminum hydroxyl pillared fluorophlogopite, the water, and the second inorganic binder is (10-40):(5-30):(30-80):(1-10).

[0011] In some embodiments, the mass ratio of the core to the outer shell is 1:(0.1-1.5).

[0012] In some embodiments, the persulfate is at least one of sodium persulfate, potassium persulfate, and ammonium persulfate.

[0013] In some embodiments, the first inorganic binder and the second inorganic binder are both at least one of silica sol, water glass, aluminum dihydrogen phosphate, bentonite sol, and kaolin sol.

[0014] In some embodiments, the particle size of the fluorophlogopite is 100-800 mesh.

[0015] In some embodiments, the particle size of the mechanically responsive piezoelectric material is 0.5 mm to 5 mm.

[0016] The second aspect of this application provides a method for preparing the aforementioned mechanically responsive piezoelectric material, comprising the following steps: A calcium source, a lutetium source, a bismuth source, a niobium source, and an iron source are mixed in stoichiometric ratios, and a molten salt medium is added. The mixture is then subjected to ball milling, a first drying, a first calcination, a first washing, and a second drying to obtain the lutetium and iron co-doped bismuth calcium niobate. The lutetium and iron co-doped bismuth calcium niobate was dispersed in a cerium salt solution, a precipitant was added to carry out a deposition reaction, and the material was obtained by a second washing, a third drying, a second calcination and reduction treatment. The fluorophlogopite was dispersed in the aluminum hydroxide pillared liquid, and after stirring, aging, third washing, fourth drying and activation treatment, the first aluminum hydroxide pillared fluorophlogopite and the second aluminum hydroxide pillared fluorophlogopite were obtained. The first aluminum hydroxide pillared fluorophlogopite was mixed with the persulfate and the first inorganic binder, and then granulated and dried to obtain the core. The piezoelectric catalytic material is mixed with the second aluminum hydroxyl pillared fluorophlogopite, the second inorganic binder and the water to form the coating slurry. The coating slurry is then coated onto the surface of the core and dried in a sixth step to obtain the mechanoresponsive piezoelectric material.

[0017] In some embodiments, the calcium source is at least one of calcium carbonate, calcium nitrate, and calcium acetate; The lutetium source is at least one of lutetium oxide, lutetium nitrate, lutetium chloride, and lutetium acetate; The bismuth source is at least one of bismuth oxide, bismuth nitrate and bismuth citrate; The niobium source is at least one of niobium pentoxide, ammonium niobium oxalate, and niobium chloride; The iron source is at least one of iron oxide, ferric nitrate, ferric chloride, ferric acetate, and ferric oxalate.

[0018] In some embodiments, the molten salt medium is at least one of sodium chloride, potassium chloride, sodium sulfate, and a sodium chloride-potassium chloride mixture; the total mass ratio of the calcium source, the lutetium source, the bismuth source, the niobium source, and the iron source to the molten salt medium is 1:(1-1.8).

[0019] In some embodiments, the cerium salt is at least one of cerium nitrate, cerium chloride, cerium sulfate, and cerium acetate; the molar ratio of Bi in the lutetium-iron co-doped bismuth niobate calcium to Ce in the cerium salt is 1:(0.02-0.30).

[0020] In some embodiments, the precipitant is at least one selected from urea, ammonia, ammonium carbonate, and sodium hydroxide.

[0021] In some embodiments, the ball milling time is 4h-24h; the first calcination temperature is 750℃-950℃, and the first calcination time is 2h-6h; the first drying and second drying temperatures are both 50℃-90℃, and the first drying time is 4h-18h.

[0022] In some embodiments, the deposition reaction temperature is 60℃-120℃, and the deposition reaction time is 3h-18h; the second calcination temperature is 200℃-400℃, and the second calcination time is 1h-5h; the reduction treatment is one of sodium borohydride solution, ascorbic acid solution, nitrogen-hydrogen mixture, or inert atmosphere heat treatment; the reduction treatment temperature is 20℃-350℃, and the reduction treatment time is 0.5h-6h.

[0023] In some embodiments, the stirring temperature is 40℃-90℃, the stirring time is 4h-24h, the aging time is 6h-48h, the activation temperature is 250℃-380℃, and the activation time is 1h-8h.

[0024] In some embodiments, the granulation temperature is 10°C-40°C.

[0025] In some embodiments, the temperature of the sixth drying is 20°C-45°C, and the drying time is 6h-48h.

[0026] A third aspect of this application provides a method for remediating farmland pollution using a mechanically responsive piezoelectric material in conjunction with agricultural organic waste, comprising the following steps: The above-mentioned mechanically responsive piezoelectric material was added to the soil to be remediated and mixed to obtain mixture A; Adding persulfate solution to mixture A yields mixture B; Periodic mechanical stress is applied to the mixture B, and then it is allowed to stand for a catalytic oxidation repair reaction to obtain treated product A; The treatment material A is subjected to soil return treatment. Agricultural organic waste is scattered on the soil surface, followed by spraying reduction bacteria solution, deep plowing to a depth of 20cm-30cm, ridging, watering to maintain the field moisture content at 50%-70%, and covering with black plastic film for 2-3 months to complete soil remediation. The amount of the mechanically responsive piezoelectric material added is 0.1%-10% of the dry weight of the soil to be remediated; The persulfate solution is at least one selected from sodium persulfate solution, potassium persulfate solution, and ammonium persulfate solution; the concentration of the persulfate solution is 0.01 mol / L-2.0 mol / L, and the amount of persulfate solution added is 0.05%-8% of the dry weight of the soil to be remediated; The frequency of the periodic mechanical stress is 5Hz-120Hz, the amplitude is 0.5mm-15mm, the duration of a single cycle is 5min-120min, and the mechanical stress is applied periodically 1-10 times. The catalytic oxidation repair reaction takes 0.5 h to 48 h and is carried out at a temperature of 5 °C to 45 °C. The agricultural organic waste is fermented cow manure or decomposed straw, and the amount of agricultural organic waste spread is 600 kg / mu to 1200 kg / mu. The cultivation of the reducing bacterial solution includes the following steps: Desulfuric Vibrio was inoculated into Postgate medium at an inoculation rate of 5%-10% and cultured in a constant temperature anaerobic incubator at 37℃ for 7-14 days. The spraying volume of the reducing bacterial solution is 10L / mu to 20L / mu.

[0027] The fourth aspect of this application provides an apparatus for implementing the above-described method of remediating farmland pollution using mechanically responsive piezoelectric materials in conjunction with agricultural organic waste, comprising a soil treatment box, a catalyst addition device, a persulfate addition device, and an eccentric vibrating plate-type piezoelectric mechanical disturbance system. The soil treatment box is used to hold the soil to be remediated; The catalyst dosing device is used to add the mechanically responsive piezoelectric material into the soil treatment tank; The persulfate dosing device is used to add the persulfate solution into the soil treatment tank; The eccentric vibrating pressure plate piezoelectric mechanical disturbance system includes a support frame, a lifting rod, a vibrating pressure plate, an eccentric vibrating motor, and a vibration controller. The vibratory plate is positioned above the soil treatment box, and the vibratory plate is connected to the support frame via the lifting rod. The lower surface of the vibrating pressure plate is provided with raised pressure teeth, which are at least one of hemispherical, conical, strip-shaped and cylindrical protrusions; The lifting rod is used to adjust the pressing depth of the vibrating plate. As the vibrating plate presses down, the protruding pressure teeth extend into the soil to be remediated inside the soil treatment box. The eccentric vibration motor is fixed to the vibration plate, and the eccentric vibration motor is used to drive the vibration plate to perform periodic movements, thereby driving the protruding pressure teeth to apply mechanical stress to the soil to be repaired in the soil treatment box. The vibration controller is electrically connected to the eccentric vibration motor, and the vibration controller is used to adjust the vibration frequency and vibration time of the eccentric vibration motor.

[0028] The beneficial effects of this application are as follows: This application breaks through the traditional soil remediation technology framework, organically integrates piezoelectric catalysis, oxidant slow release and biological stabilization, and constructs a new system for the continuous treatment of farmland compound pollution with mechanical disturbance as the driving force, core-shell composite material as the core and physical-chemical remediation and biological remediation connected before and after, thus opening up a practical path for piezoelectric catalysis technology to be applied to soil remediation engineering.

[0029] In terms of material design, the core-shell composite particle structure arranges persulfate slow-release storage and piezoelectric catalytic response activation in an orderly spatial arrangement, enabling the oxidant to be released uniformly from the core and efficiently activated near the catalytic sites on the shell. This fundamentally solves the problems of rapid reagent loss and spatiotemporal misalignment between catalytic sites and oxidant in traditional dosing methods, significantly improving oxidant utilization efficiency. The hydroxyl aluminum pillar fluorophlogopite simultaneously serves as a dual carrier for the fixation and slow release of oxidant and the stable loading of catalytic materials, giving the particles good mechanical strength and environmental durability.

[0030] In the catalytic system, lutetium and iron dual-ion co-doping precisely controls the lattice strain and defect concentration of bismuth calcium niobate. Combined with the interfacial charge extraction effect of surface defect-type cerium oxide, a complete energy conversion chain is constructed from mechanical energy input to piezoelectric generation, charge separation and oxidant activation. This significantly improves the piezoelectric response and carrier separation efficiency, gets rid of the inherent defect of rapid deactivation of iron ions in traditional iron-based activation systems, and avoids secondary pollution such as iron mud and soil acidification from the source.

[0031] At the engineering and environmental levels, the material formulation and operating parameters are adaptable to a wide range of farmland conditions, from acidic to slightly alkaline, and from sandy to clayey. The remediation temperature covers year-round climatic conditions, and it is applicable to both ex-situ and in-situ scenarios. The accompanying disturbance device integrates vibration, compression, and shearing combined effects, with adjustable parameters and integrated construction, significantly reducing energy consumption and labor time. The entire process produces no toxic byproducts. The subsequent microbial remediation simultaneously decomposes sulfates and immobilizes heavy metals, restoring the soil to agricultural standards. The raw materials are conventional and inexpensive, combining environmental benefits with economic feasibility. Attached Figure Description

[0032] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of an apparatus for implementing a method of remediating farmland pollution using mechanically responsive piezoelectric materials in conjunction with agricultural organic waste, according to one embodiment. Figure 2This is a cross-sectional layered structural diagram of an apparatus for implementing a method of remediating farmland pollution using mechanically responsive piezoelectric materials in conjunction with agricultural organic waste, according to one embodiment. Figure 3 SEM images of the lutetium and iron co-doped bismuth calcium niobate and piezoelectric catalytic material prepared in Example 1; Figure 4 The image shows the XRD pattern of the piezoelectric catalytic material prepared in Example 1. Figure 5 This is a diagram showing the remediation effect of contaminated soil obtained after the catalytic oxidation remediation reaction in Example 1. Figure 6 This is a graph showing the accumulation of soluble sulfates after the catalytic oxidation remediation reaction in Example 1. Figure 7 This is a graph showing the degradation of soluble sulfates obtained after soil remediation in Example 1.

[0033] In the attached diagram: 1-Support frame; 2-Lifting rod; 3-Vibration pressure plate; 31-Raised pressure teeth; 4-Eccentric vibration motor; 5-Vibration controller; 6-Soil treatment box; 7-Catalyst dosing device; 8-Persulfate dosing device. Detailed Implementation

[0034] The present application will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the application. Furthermore, it should be understood that after reading the contents of this application, those skilled in the art can make various alterations or modifications to this application, and these equivalent forms also fall within the scope defined by the appended claims.

[0035] In the description of this specification, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature.

[0036] This application provides a mechanically responsive piezoelectric material, comprising a core and a shell covering the core, wherein the core is obtained by mixing and granulating a first raw material, the first raw material comprising a first aluminum hydroxyl-pillared fluorophlogopite, persulfate and a first inorganic binder; The outer shell is formed by a coating slurry, which includes a piezoelectric catalytic material, a second hydroxyl aluminum-pillared fluorophlogopite, water, and a second inorganic binder. The piezoelectric catalyst is lutetium niobate calcium co-doped with iron and modified with defect-type cerium oxide, with the general chemical formula Ca. 1-α Lu α Bi2Nb 2-β Fe β O9-δ @CeO 2-x Where 0.05≤α≤0.3, 0.05≤β≤0.3, and β≥α / 2; 0.01≤δ≤0.275, and δ=β-α / 2; 0.02≤x≤0.35; Both the first hydroxyl aluminum-pillared fluorophlogopite and the second hydroxyl aluminum-pillared fluorophlogopite were obtained by modifying fluorophlogopite with hydroxyl aluminum-pillared liquid.

[0037] The mechanically responsive piezoelectric material provided in this application is used for contaminated soil remediation. It adopts a core-shell composite particle structure, consisting of an inner core and an outer shell covering the core's surface. The design of this layered structure aims to spatially arrange the slow-release storage of the oxidant and the piezoelectric catalytic response activation in an orderly manner, ensuring that the two are both independent and functionally interconnected, thereby forming a continuous and efficient catalytic oxidation system under soil mechanical disturbance conditions.

[0038] The core of this mechanoresponsive piezoelectric material is obtained by mixing and granulating a first raw material, which includes a first aluminum hydroxyl-pillared fluorophlogopite, persulfate, and a first inorganic binder. Persulfate, as the main oxidant in the system, functions to generate reactive oxygen species after activation, thereby degrading organic pollutants. The first aluminum hydroxyl-pillared fluorophlogopite serves as the core's carrier framework. Through its well-developed interlayer pores and enhanced ion exchange capacity formed after modification with the aluminum hydroxyl-pillar, it adsorbs and fixes persulfate molecules, allowing for a uniform and slow release of persulfate into the soil water environment, avoiding the waste and residue risks caused by a large-scale dissolution of the oxidant at once. The first inorganic binder binds the two components together during the granulation process, giving the core particles a certain mechanical strength, making them less prone to breakage and disintegration during subsequent coating processes and soil tillage disturbances.

[0039] The shell of this mechanoresponsive piezoelectric material is formed by a coating slurry, which includes a piezoelectric catalytic material, a second aluminum hydroxyl-pillared fluorophlogopite, water, and a second inorganic binder. The shell, located on the outermost layer of the particle, is the part that directly bears the mechanical stress of the soil. Therefore, placing the piezoelectric catalytic material within the shell allows it to receive maximum mechanical energy input and deform, thereby generating piezoelectric polarization charges. The second aluminum hydroxyl-pillared fluorophlogopite also acts as a carrier and framework within the shell, stabilizing the piezoelectric catalytic material and preventing powder loss with soil and water. Furthermore, its interlayer structure facilitates the migration and accumulation of water molecules and persulfate slowly released from the core to the catalytic sites. Water serves as the dispersion medium for the coating slurry, enabling the components to form a uniform, coatable slurry system. The second inorganic binder, after drying, solidifies the components of the shell into a coating layer with a certain strength, achieving a tight bond between the shell and the core.

[0040] The piezoelectric catalyst in the shell of this mechanoresponsive piezoelectric material is lutetium-iron co-doped bismuth calcium niobate modified with defect-type cerium oxide. This material uses a layered perovskite structure of bismuth calcium niobate as the piezoelectric substrate. The lattice strain and defect concentration are controlled by co-doping lutetium and iron ions, thereby improving the conversion efficiency of mechanical energy to electrical energy. Here, α represents the substitution ratio of lutetium at calcium sites, and β represents the substitution ratio of iron at niobium sites. Both are controlled within 0.05-0.3, and satisfy β≥α / 2. This constraint ensures that the oxygen vacancy concentration introduced by doping is within a reasonable range. δ, as the oxygen vacancy quantification parameter, is determined by the difference between β and α, ranging from 0.01-0.275. Values ​​below this range indicate insufficient doping and limited improvement in piezoelectric response; values ​​above this range indicate excessive lattice distortion, leading to a decrease in piezoelectric performance. Furthermore, defect-type cerium oxide (CeO) is further modified onto the surface of the aforementioned co-doped piezoelectric substrate. 2-x Where x represents the oxygen vacancy content, controlled between 0.02 and 0.35; defective cerium oxide relies on Ce 3+ With Ce 4+ The reversible cycle and abundant oxygen vacancies between the piezoelectric material and the oxidant can efficiently capture the polarization charge generated by the piezoelectric substrate, suppress the recombination of electrons and holes, and continuously transfer electrons to persulfate molecules to promote their activation, thereby building a stable interfacial charge migration channel between the piezoelectric material and the oxidant.

[0041] Both the first and second aluminum hydroxyl-pillared fluorophlogopite were obtained by modifying fluorophlogopite with an aluminum hydroxyl-pillaring solution. Fluorophlogopite itself has a layered silicate structure. After treatment with the aluminum hydroxyl-pillaring solution, the aluminum hydroxyl polymeric cations enter the interlayer space of the mica, widening the interlayer spacing. Upon activation, a pillared structure is formed, significantly improving the material's specific surface area, interlayer porosity, and ion exchange capacity. Based on this modification characteristic, the aluminum hydroxyl-pillared fluorophlogopite can adsorb and immobilize persulfate in its core and achieve slow release, while in its outer shell it can stably support piezoelectric catalytic materials and promote mass migration, becoming a key carrier component connecting the two functional modules of oxidant storage and piezoelectric catalytic activation.

[0042] Overall, the mechanically responsive piezoelectric material provided in this application organically combines a slow-release persulfate core with a piezoelectric catalytic shell through a core-shell structure. When external mechanical disturbances are applied to the particles, the piezoelectric catalytic material in the shell first undergoes deformation under stress to generate piezoelectric polarization charges. These charges are extracted and transferred through the interface of defective cerium oxide, activating the persulfate that is slowly released from the core to the vicinity of the catalytic site in the shell, thereby generating reactive oxygen species to oxidize and degrade organic pollutants in the soil. The hydroxyl aluminum pillared fluorophlogopite configured in both the core and the shell plays a synergistic role in the fixation and slow release of oxidants and the stable loading of catalytic materials, respectively, enabling the entire system to continuously and stably output catalytic oxidation efficiency under soil disturbance conditions.

[0043] Preferably, the molar ratio of Ca, Lu, Bi, Nb and Fe in lutetium and iron co-doped bismuth calcium niobate is 0.85:0.15:2:1.98:0.02.

[0044] In some embodiments, the defective cerium oxide is loaded onto the surface of the lutetium-iron co-doped bismuth niobate calcium niobate at an amount of 0.5%-15% of the mass of the lutetium-iron co-doped bismuth niobate calcium niobate.

[0045] In some embodiments, the aluminum hydroxyl pillared liquid is prepared by reacting an aluminum salt solution with an alkaline solution, wherein the alkaline solution contains OH... - With Al in the aluminum salt solution 3+ The molar ratio is 1:(1.5-2.8); The aluminum salt is at least one of aluminum chloride, aluminum nitrate, aluminum sulfate, and aluminum isopropoxide; The alkaline solution is at least one of sodium hydroxide, potassium hydroxide, ammonia, and sodium carbonate; The fluorophlogopite and the aluminum hydroxide pillar solution contain Al 3+ The mass ratio is 1:(0.02-0.50).

[0046] In some embodiments, the mass ratio of the first aluminum hydroxyl pillared fluorophlogopite, the persulfate, and the first inorganic binder is (35-75):(10-45):(1-15).

[0047] In some embodiments, the mass ratio of the piezoelectric catalytic material, the second aluminum hydroxyl pillared fluorophlogopite, the water, and the second inorganic binder is (10-40):(5-30):(30-80):(1-10).

[0048] In some embodiments, the mass ratio of the core to the outer shell is 1:(0.1-1.5).

[0049] In some embodiments, the persulfate is at least one of sodium persulfate, potassium persulfate, and ammonium persulfate.

[0050] In some embodiments, the first inorganic binder and the second inorganic binder are both at least one of silica sol, water glass, aluminum dihydrogen phosphate, bentonite sol, and kaolin sol.

[0051] In some embodiments, the particle size of the fluorophlogopite is 100-800 mesh.

[0052] In some embodiments, the particle size of the mechanoresponsive piezoelectric material is 0.5 mm to 5 mm. More preferably, the particle size of the mechanoresponsive piezoelectric material is 1 mm to 3 mm.

[0053] In some embodiments, the mechanically responsive piezoelectric material comprises, by mass fraction: 10%-40% piezoelectric catalyst, 30%-70% of the sum of the mass of the first aluminum hydroxyl-pillared fluorophlogopite and the second aluminum hydroxyl-pillared fluorophlogopite, 10%-40% persulfate, and 1-15% of the mass of the sum of the mass of the first inorganic binder and the second inorganic binder, and the sum of the mass fractions of each component is 100%.

[0054] This application also provides a method for preparing the above-mentioned mechanically responsive piezoelectric material, comprising the following steps: A calcium source, a lutetium source, a bismuth source, a niobium source, and an iron source are mixed in stoichiometric ratios, and a molten salt medium is added. The mixture is then subjected to ball milling, a first drying, a first calcination, a first washing, and a second drying to obtain the lutetium and iron co-doped bismuth calcium niobate. The lutetium and iron co-doped bismuth calcium niobate was dispersed in a cerium salt solution, a precipitant was added to carry out a deposition reaction, and the material was obtained by a second washing, a third drying, a second calcination and reduction treatment. The fluorophlogopite was dispersed in the aluminum hydroxyl pillared liquid, and after stirring, aging, third washing, fourth drying and activation treatment, the first aluminum hydroxyl pillared fluorophlogopite and the second aluminum hydroxyl pillared fluorophlogopite were obtained (here the prepared aluminum hydroxyl pillared fluorophlogopite is divided into two parts, namely the first aluminum hydroxyl pillared fluorophlogopite and the second aluminum hydroxyl pillared fluorophlogopite, wherein the first aluminum hydroxyl pillared fluorophlogopite is used for core preparation and the second aluminum hydroxyl pillared fluorophlogopite is used for shell preparation). The first aluminum hydroxide pillared fluorophlogopite was mixed with the persulfate and the first inorganic binder, and then granulated and dried to obtain the core. The piezoelectric catalytic material is mixed with the second aluminum hydroxyl pillared fluorophlogopite, the second inorganic binder and the water to form the coating slurry. The coating slurry is then coated onto the surface of the core and dried in a sixth step to obtain the mechanoresponsive piezoelectric material.

[0055] In some embodiments, the calcium source is at least one of calcium carbonate, calcium nitrate, and calcium acetate; The lutetium source is at least one of lutetium oxide, lutetium nitrate, lutetium chloride, and lutetium acetate; The bismuth source is at least one of bismuth oxide, bismuth nitrate and bismuth citrate; The niobium source is at least one of niobium pentoxide, ammonium niobium oxalate, and niobium chloride; The iron source is at least one of iron oxide, ferric nitrate, ferric chloride, ferric acetate, and ferric oxalate.

[0056] The above calculations for the calcium, lutetium, bismuth, niobium, and iron sources are based on the molar ratio Ca:Lu:Bi:Nb:Fe = (1-α):α:2:(2-β):β. Here, the values ​​of α and β correspond to the general chemical formula Ca of piezoelectric catalysts. 1-α Lu α Bi2Nb 2-β Fe β O 9-δ @CeO 2-x Consistent.

[0057] In some embodiments, the molten salt medium is at least one of sodium chloride, potassium chloride, sodium sulfate, and a sodium chloride-potassium chloride mixture; the total mass ratio of the calcium source, the lutetium source, the bismuth source, the niobium source, and the iron source to the molten salt medium is 1:(1-1.8).

[0058] In some embodiments, the cerium salt is at least one of cerium nitrate, cerium chloride, cerium sulfate, and cerium acetate; the molar ratio of Bi in the lutetium-iron co-doped bismuth niobate calcium to Ce in the cerium salt is 1:(0.02-0.30).

[0059] In some embodiments, the precipitant is at least one selected from urea, ammonia, ammonium carbonate, and sodium hydroxide.

[0060] In some embodiments, the ball milling time is 4h-24h; the first calcination temperature is 750℃-950℃, and the first calcination time is 2h-6h; the first drying and second drying temperatures are both 50℃-90℃, and the first drying time is 4h-18h.

[0061] In some embodiments, the deposition reaction temperature is 60℃-120℃, and the deposition reaction time is 3h-18h; the second calcination temperature is 200℃-400℃, and the second calcination time is 1h-5h; the reduction treatment is one of sodium borohydride solution, ascorbic acid solution, nitrogen-hydrogen mixture, or inert atmosphere heat treatment; the reduction treatment temperature is 20℃-350℃, and the reduction treatment time is 0.5h-6h.

[0062] In some embodiments, the stirring temperature is 40℃-90℃, the stirring time is 4h-24h, the aging time is 6h-48h, the activation temperature is 250℃-380℃, and the activation time is 1h-8h.

[0063] In some embodiments, the granulation temperature is 10°C-40°C.

[0064] In some embodiments, the temperature of the sixth drying is 20°C-45°C, and the drying time is 6h-48h.

[0065] This application also provides a method for remediating farmland pollution using mechanically responsive piezoelectric materials in conjunction with agricultural organic waste, comprising the following steps: The above-mentioned mechanically responsive piezoelectric material was added to the soil to be remediated and mixed to obtain mixture A; Adding persulfate solution to mixture A yields mixture B; Periodic mechanical stress is applied to the mixture B, and then it is allowed to stand for a catalytic oxidation repair reaction to obtain treated product A; The treatment material A is subjected to soil return treatment. Agricultural organic waste is scattered on the soil surface, followed by spraying reduction bacteria solution, deep plowing to a depth of 20cm-30cm, ridging, watering to maintain the field moisture content at 50%-70%, and covering with black plastic film for 2-3 months to complete soil remediation. The amount of the mechanically responsive piezoelectric material added is 0.1%-10% of the dry weight of the soil to be remediated; The persulfate solution is at least one selected from sodium persulfate solution, potassium persulfate solution, and ammonium persulfate solution; the concentration of the persulfate solution is 0.01 mol / L-2.0 mol / L, and the amount of persulfate solution added is 0.05%-8% of the dry weight of the soil to be remediated; The frequency of the periodic mechanical stress is 5Hz-120Hz, the amplitude is 0.5mm-15mm, the duration of a single cycle is 5min-120min, and the mechanical stress is applied periodically 1-10 times. The catalytic oxidation repair reaction takes 0.5 h to 48 h and is carried out at a temperature of 5 °C to 45 °C. The agricultural organic waste is fermented cow manure or decomposed straw, and the amount of agricultural organic waste spread is 600 kg / mu to 1200 kg / mu. The cultivation of the reducing bacterial solution includes the following steps: Purchased *Nitratidesulfovibrio vulgaris* (deposited at Guangdong Provincial Microbial Culture Collection Center, accession number GDMCC NO. 1.3160) was inoculated into Postgate medium at an inoculation rate of 5%-10% and cultured in a constant temperature anaerobic incubator at 37℃ for 7-14 days; the resulting reducing bacterial solution had a concentration ≥10 μL. 8 CFU / g; The spraying volume of the reducing bacterial solution is 10L / mu to 20L / mu.

[0066] The method for remediating farmland pollution provided in this application combines physicochemical catalytic oxidation with biological stabilization. First, mechanical disturbance drives a piezoelectric catalytic system (the aforementioned mechanically responsive piezoelectric material) to rapidly degrade organic pollutants in the soil (mainly including one or more of petroleum hydrocarbons, polycyclic aromatic hydrocarbons, chlorinated organics, pesticides, antibiotics, dyes, and phenolic pollutants). Then, the synergistic effect of reducing bacteria and agricultural organic waste is used to subsequently stabilize oxidation byproducts and activated heavy metals, thereby achieving integrated remediation of farmland contaminated soil.

[0067] First, the aforementioned mechanically responsive piezoelectric material is added to the soil to be remediated and mixed thoroughly to obtain mixture A. The amount of piezoelectric material added is controlled at 0.1%-10% of the dry weight of the soil to be remediated. This dosage range covers different working conditions from light to heavy pollution. If the dosage is too low, there will be insufficient catalytic sites and limited degradation efficiency. If the dosage is too high, it will not only increase costs but may also affect the uniform reception of mechanical energy due to particle agglomeration. The purpose of thorough mixing is to ensure that the core-shell catalytic particles are uniformly dispersed in the soil system, ensuring that every polluted area can obtain a piezoelectric catalytic response.

[0068] Subsequently, a persulfate solution was added to mixture A to obtain mixture B. The persulfate solution was selected from at least one of sodium persulfate solution, potassium persulfate solution, and ammonium persulfate solution, with a concentration controlled between 0.01 mol / L and 2.0 mol / L, and the amount added was 0.05%-8% of the dry weight of the soil to be remediated. Although the core of the piezoelectric material already contained slow-release persulfate, the additional addition of a certain concentration of persulfate solution at the initial stage of remediation could quickly establish an initial concentration gradient of oxidant, forming a rapid start-up and continuous supply synergy with the long-term slow release of the core. The addition in solution form also facilitated the rapid penetration and diffusion of the oxidant in the soil pores, ensuring full contact with the catalytic sites on the outer shell surface.

[0069] Next, periodic mechanical stress is applied to mixture B, followed by a catalytic oxidative remediation reaction. The periodic mechanical stress (compression, vibration, and shear) is directly transmitted to the core-shell catalytic particles in the soil, causing lattice deformation and piezoelectric polarization of the lutetium iron co-doped bismuth niobate calcium in the outer shell. The surface-modified defective cerium oxide then undergoes Ce... 3+ With Ce 4+ The reversible cycle extracts polarized charges and transfers them to surrounding persulfate molecules, causing persulfate to break down and generate reactive oxygen species such as sulfate radicals, thereby oxidizing and degrading organic pollutants in the soil. The periodic application rather than continuous pressure method allows the polarized lattice to fully relax during stress intervals, while also allowing time for the oxidant and pollutants to diffuse to the catalytic interface, avoiding catalytic fatigue and charge recombination caused by continuous high-load operation. The adjustable range of frequency and amplitude is adapted to different soil textures from sandy soil to clay soil, ensuring that catalytic particles in various soil types can obtain sufficient deformation. The temperature range of the catalytic oxidation reaction covers the annual temperature range of farmland in most parts of my country, making this remediation method not significantly limited by seasonal low temperatures.

[0070] After the physical and chemical remediation phase, treatment A is returned to the soil. Agricultural organic waste is evenly spread on the soil surface, followed by spraying with reducing bacteria solution, deep plowing, ridging, and watering to maintain the field moisture content. Finally, black plastic film (black polyethylene film) is used for covering to complete the entire soil remediation process. Agricultural organic waste plays multiple roles at this stage. It can improve soil aggregate structure, provide a colony carrier for microorganisms, and serve as a carbon source and electron donor to support the metabolic activities of reducing bacteria. In the anaerobic environment, desulfurizing Vibrio in the reducing bacterial solution reduces the sulfate produced in the early oxidation stage to sulfides. The sulfides can combine with heavy metal ions in the soil to form insoluble precipitates, thereby achieving in-situ stabilization of heavy metals. Deep plowing fully mixes agricultural organic waste and bacterial solution into the soil layer. Ridging and watering create a moist living environment for anaerobic microorganisms. Black plastic film covering can isolate air, maintain soil temperature and soil moisture, significantly promote the reproduction of desulfurizing Vibrio and reduce soil redox potential, creating favorable anaerobic conditions for sulfate reduction and heavy metal precipitation. The covering cycle of 2 to 3 months is sufficient for microbial metabolism to proceed fully, reducing the soluble sulfate content to a safe level and effectively controlling the concentration of heavy metal leaching.

[0071] Overall, this method for remediating farmland pollution rapidly reduces the load of organic pollutants through piezoelectric catalytic oxidation driven by mechanical disturbance in the early stage, and then utilizes an anaerobic stabilization system of agricultural organic waste coupled with desulfurizing Vibrio bacteria in the later stage to decompose oxidation byproducts and immobilize heavy metals. The two stages are connected and complementary, which not only solves the problems of sulfate accumulation and heavy metal activation in simple chemical oxidation, but also avoids the shortcomings of the long cycle of simple bioremediation. It provides an efficient, low-carbon and engineerable remediation path for farmland soil with complex pollution.

[0072] In some implementations, the contaminated soil is first pretreated, the pretreatment including the following steps: Remove impurity particles with a diameter >50mm from the contaminated soil, crush the contaminated soil to a particle size of 0.5mm-30mm, and adjust the moisture content of the contaminated soil to 20%-85% and the pH to 3.0-8.0 to obtain the soil to be remediated.

[0073] Removing impurity particles is to avoid the uniform transmission of stress caused by hard objects during subsequent mechanical disturbance, and also to prevent sharp particles from causing excessive wear on the outer shell of the catalyst particles. Breaking the soil to a suitable particle size can increase the contact area between soil particles and catalyst materials, allowing oxidants and reactive oxygen species to diffuse more fully into the microenvironment where pollutants reside. The control of moisture content is directly related to the dissolution and migration of persulfate and the effective conduction of piezoelectric charges in soil pore water. If the moisture content is too low, the migration of substances will be hindered; if it is too high, mechanical energy will be excessively dissipated by water. The setting of the pH range takes into account both the stability of the piezoelectric catalyst material and the acid-base adaptability of the persulfate activation reaction, so that the method can operate normally under a wide range of farmland soil conditions from acidic to weakly alkaline.

[0074] like Figure 1 and Figure 2 As shown, this application also provides an apparatus for implementing the above-described method of using mechanically responsive piezoelectric materials in conjunction with agricultural organic waste to remediate farmland pollution, including a soil treatment box, a catalyst dosing device, a persulfate dosing device, and an eccentric vibrating plate piezoelectric mechanical disturbance system; The soil treatment box is used to hold the soil to be remediated; The catalyst dosing device is used to add the mechanically responsive piezoelectric material into the soil treatment tank; The persulfate dosing device is used to add the persulfate solution into the soil treatment tank; The eccentric vibrating pressure plate piezoelectric mechanical disturbance system includes a support frame, a lifting rod, a vibrating pressure plate, an eccentric vibrating motor, and a vibration controller. The vibratory plate is positioned above the soil treatment box, and the vibratory plate is connected to the support frame via the lifting rod. The lower surface of the vibrating pressure plate is provided with raised pressure teeth, which are at least one of hemispherical, conical, strip-shaped and cylindrical protrusions; The lifting rod is used to adjust the pressing depth of the vibrating plate. As the vibrating plate presses down, the protruding pressure teeth extend into the soil to be remediated inside the soil treatment box. The eccentric vibration motor is fixed to the vibration plate, and the eccentric vibration motor is used to drive the vibration plate to perform periodic movements, thereby driving the protruding pressure teeth to apply mechanical stress to the soil to be repaired in the soil treatment box. The vibration controller is electrically connected to the eccentric vibration motor, and the vibration controller is used to adjust the vibration frequency and vibration time of the eccentric vibration motor.

[0075] This device integrates functional units such as soil bearing capacity, reagent dosing, and mechanical disturbance to stimulate piezoelectric catalysis, enabling the physicochemical remediation stage of contaminated soil to be completed in an orderly manner within the same treatment space, avoiding the cumbersome operation and material loss caused by rotating multiple devices.

[0076] The entire system mainly consists of four parts: a soil treatment tank, a catalyst dosing device, a persulfate dosing device, and an eccentric vibrating plate piezoelectric mechanical disturbance system. The soil treatment tank serves as the carrying space for the entire remediation operation, containing the pre-treated soil to be remediated. It provides a well-defined and easily operable reaction area for subsequent reagent mixing and mechanical disturbance. The tank's spaciousness also prevents the soil from scattering outwards when subjected to vibration and compression, ensuring that mechanical energy is concentrated on the soil and catalyst particle system within the tank.

[0077] The catalyst dosing device is used to add the aforementioned mechanically responsive piezoelectric material into the soil treatment tank. Since the piezoelectric material is a granular solid, the dosing device can be in the form of a storage silo combined with a quantitative feeding mechanism. For example, a screw feeder or vibrating feeder can be installed below the storage silo, and the dosing controller controls the operating time and speed of the feeding mechanism according to the preset dosing amount, so that the catalyst particles are evenly scattered into the soil treatment tank according to the set mass. The persulfate dosing device is used to add persulfate solution into the tank. This device can be in the form of a storage tank combined with a metering pump. For example, the persulfate solution in the storage tank can be transported to the spray head above the soil treatment tank through a pipeline by a diaphragm metering pump or a peristaltic pump. The dosing controller controls the pump flow rate and running time according to the preset concentration and dosing amount to achieve quantitative and uniform spraying of the oxidant solution. The two dosing devices are independent of each other and each performs its own function. They can be added separately according to the order of the remediation process, or the dosage can be flexibly controlled according to the degree of soil pollution, so that the catalyst particles and oxidant have a relatively uniform initial distribution when they enter the soil system.

[0078] The core functional unit of the device is an eccentric vibrating plate piezoelectric mechanical disturbance system, which consists of a support frame, a lifting rod, a vibrating plate, an eccentric vibrating motor, and a vibration controller. The support frame serves as the load-bearing foundation of the entire disturbance system, providing stable suspension and support for the lifting rod and the vibrating plate. The vibrating plate is positioned directly above the soil treatment box and connected to the support frame via the lifting rod. The lifting rod drives the vibrating plate to move vertically up and down, thereby adjusting the pressing depth of the vibrating plate relative to the soil surface inside the box. As the vibrating plate presses downwards, the protruding pressure teeth on its lower surface extend into the soil to be treated within the soil treatment box, allowing the mechanical force to be directly transmitted to the deeper soil layers rather than remaining only on the surface.

[0079] The lower surface of the vibrating plate is equipped with raised pressure teeth. The shape of the pressure teeth can be selected from at least one of hemispherical, conical, strip, and cylindrical shapes. After the pressure teeth of different shapes penetrate into the soil, they will produce different modes of squeezing, shearing, and kneading effects on the surrounding catalytic particles, thereby stimulating the piezoelectric deformation of the core-shell catalytic particles in multiple dimensions. The presence of raised pressure teeth also significantly increases the effective contact area between the plate and the soil, making the transfer of mechanical energy more complete and uniform, and avoiding the problem that only the surface soil is subjected to force when the plate is pressed, while the deep particles do not receive sufficient deformation stimulation.

[0080] An eccentric vibration motor is fixedly mounted on the vibrating pressure plate. During operation, the high-speed rotation of the eccentric block generates periodic excitation force, which drives the vibrating pressure plate to vibrate periodically. This, in turn, causes the protruding pressure teeth on the lower surface to continuously apply mechanical stress to the soil to be remediated in the soil treatment box. This method of directly driving the pressure plate to vibrate by the eccentric vibration motor has a simple structure and direct transmission of excitation force. It can efficiently transmit vibration energy to every catalytic particle in the soil, causing the piezoelectric material in the shell to undergo lattice deformation and generate polarization charge, thereby initiating the subsequent piezoelectric catalytic oxidation process.

[0081] The vibration controller is electrically connected to the eccentric vibration motor to adjust the vibration frequency and vibration time of the eccentric vibration motor. The vibration controller can flexibly set the appropriate vibration frequency and single working time according to the soil texture, pollution level and response characteristics of the catalytic particles, and realize multi-cycle cyclic disturbance, so that the piezoelectric catalytic system is always in a highly efficient excitation state during the remediation process, while avoiding energy waste and excessive damage to soil structure that may be caused by continuous high-intensity vibration.

[0082] Overall, the device provides a stable remediation space through a soil treatment box, achieves precise replenishment of catalytic materials and oxidants through two independent dosing devices, and directly applies controllable periodic mechanical stress to the catalytic particles in the soil using an eccentric vibrating plate piezoelectric mechanical disturbance system. This provides a compact, easy-to-operate, and parameter-adjustable engineering implementation platform for the physicochemical catalytic oxidation stage in the aforementioned remediation method, allowing the catalytic efficiency of the mechanically responsive piezoelectric materials to be fully released in actual soil remediation scenarios.

[0083] In some embodiments, the vibrating pressure plate is one of stainless steel plate, polytetrafluoroethylene plate, polypropylene plate or ceramic composite plate.

[0084] In some embodiments, the thickness of the vibrating pressure plate is 3mm-30mm.

[0085] In some embodiments, the length of the raised pressure teeth in the vertical direction is 2mm-30mm; the center distance between adjacent raised pressure teeth is 5mm-80mm.

[0086] In some embodiments, the vibration frequency of the vibrating plate is 5Hz-120Hz; the amplitude of the vibrating plate is 0.5mm-15mm.

[0087] In some embodiments, the protruding pressure teeth extend into the soil to be treated to a degree of 5%-80% of the soil thickness.

[0088] In some embodiments, the power of the eccentric vibration motor is 50W-1500W; the single vibration treatment time is 5min-120min; and the number of vibration treatments is 1-10 times.

[0089] To provide a clearer and more detailed description of the modified molecular sieves, their preparation methods, and applications provided in the embodiments of this application, the following description will be provided in conjunction with specific embodiments. Example 1

[0090] A mechanically responsive piezoelectric material with a particle size of 1 mm to 3 mm, comprising a core with a mass ratio of 1:0.8 and a shell covering the core.

[0091] The core is obtained by mixing and granulating the first raw material, which includes a first hydroxyl aluminum pillar fluorophlogopite, persulfate (sodium persulfate) and a first inorganic binder (silica sol) in a mass ratio of 55:30:8.

[0092] The outer shell is formed by a coating slurry, which includes a piezoelectric catalyst material in a mass ratio of 25:18:52:5, a second hydroxyl aluminum-pillared fluorophlogopite, deionized water, and a second inorganic binder (silica sol). The piezoelectric catalyst material is lutetium-iron co-doped calcium bismuth niobate modified with defect-type cerium oxide, with the chemical formula Ca. 0.85 Lu 0.15 Bi2Nb 1.8 Fe 0.2 O 8.875 @CeO 1.85 The loading of defective cerium oxide on the surface of lutetium-iron co-doped bismuth niobate calcium is 8% of the mass of lutetium-iron co-doped bismuth niobate calcium.

[0093] Both the first and second aluminum hydroxyl-pillared fluorophlogopite were obtained by modifying fluorophlogopite (300 mesh) with an aluminum hydroxyl-pillaring solution. The aluminum hydroxyl-pillaring solution was prepared by reacting an aluminum salt solution (aluminum chloride) with an alkaline solution (ammonia). The OH- in the alkaline solution... - With Al in aluminum salt solution 3+ The molar ratio was 1:2.2; Al in the fluorophlogopite and aluminum hydroxyl columnar liquid 3+ The mass ratio is 1:0.2.

[0094] The mechanically responsive piezoelectric material comprises, by mass fraction: 26% piezoelectric catalyst, 42% (sum of first hydroxyl aluminum-pillared fluorophlogopite and second hydroxyl aluminum-pillared fluorophlogopite), 27% persulfate, and 5% (sum of first inorganic binder and second inorganic binder).

[0095] The preparation method of this mechanically responsive piezoelectric material includes the following steps: Calcium source (calcium carbonate), lutetium source (lutetium oxide), bismuth source (bismuth oxide), niobium source (niobium pentoxide), and iron source (iron oxide) were mixed in stoichiometric ratios (molar ratio Ca:Lu:Bi:Nb:Fe = 0.85:0.15:2:1.8:0.2). A molten salt medium (a sodium chloride-potassium chloride mixture, with a sodium chloride to potassium chloride mass ratio of 1:1, and the total mass of the calcium, lutetium, bismuth, niobium, and iron sources being 1:1.4 of the molten salt medium) was added. The mixture underwent ball milling (planetary ball mill, 12 h, 1000 r / min), first drying (70℃ for 10 h), first calcination (850℃ for 3 h), first washing (washed three times with deionized water after cooling), and second drying (70℃) to obtain lutetium and iron co-doped bismuth calcium niobate (SEM image of lutetium and iron co-doped bismuth calcium niobate is shown below). Figure 3 As shown in a and b in the figure, a is the surface morphology and b is the fracture morphology. Lutetium and iron co-doped bismuth calcium niobate was dispersed in a cerium salt (cerium nitrate) solution (the molar ratio of Bi in the lutetium and iron co-doped bismuth calcium niobate to Ce in the cerium salt was 1:0.12). A precipitant (urea) was added for deposition (stirring at 90℃ for 10 h). The mixture underwent a second washing (washing and filtration to obtain the solid), a third drying, a second calcination (calcination at 300℃ for 3 h), and a reduction treatment (reduction treatment at room temperature for 2 h using 0.2 mol / L sodium borohydride solution) to obtain a piezoelectric catalytic material (SEM image of the piezoelectric catalytic material is shown below). Figure 3 As shown in c and d, c represents the surface morphology, and d represents the fracture morphology; the XRD pattern of the piezoelectric catalytic material is shown in... Figure 4 As shown, Figure 4 (where a is bismuth calcium niobate and b is a piezoelectric catalytic material). Fluorophyllite was dispersed in aluminum hydroxyl columnar liquid, and after stirring (stirring at 60℃ for 12h), aging (24h), third washing, fourth drying and activation treatment (activation at 320℃ for 4h), first aluminum hydroxyl columnar fluorophlogopite and second aluminum hydroxyl columnar fluorophlogopite were obtained. The first hydroxyl aluminum pillar fluorophlogopite was mixed with persulfate and the first inorganic binder, and then granulated (granulated at 25°C) and dried to obtain the core. A piezoelectric catalyst material is mixed with a second hydroxyl aluminum pillar fluorophlogopite, a second inorganic binder and water to form a coating slurry. The coating slurry is then coated onto the surface of the core (dispersing the core in the coating slurry). After a sixth drying process (drying at 30°C for 30 hours), a mechanically responsive piezoelectric material is obtained.

[0096] A method for remediating farmland pollution using mechanically responsive piezoelectric materials in conjunction with agricultural organic waste includes the following steps: Remove impurity particles with a diameter >50mm from the contaminated soil, crush the contaminated soil to a particle size of 5mm, and adjust the moisture content of the contaminated soil to 55% and the pH to 7.2 to obtain the soil to be remediated. Add the mechanically responsive piezoelectric material prepared above (3% of the dry weight of the soil to be remediated) to the soil to be remediated, mix (manually stir and mix) to obtain mixture A; Add persulfate solution (sodium persulfate solution, concentration 0.5 mol / L, added at 3% of the dry weight of the soil to be remediated) to mixture A to obtain mixture B; Periodic mechanical stress was applied to mixture B (the frequency of the periodic mechanical stress was 40 Hz, the amplitude was 6 mm, the duration of a single cycle was 40 min, and the periodic application of mechanical stress was repeated 3 times), and then the mixture was allowed to stand for catalytic oxidation repair reaction (25 °C, 10 h) to obtain treated material A. For treatment A, soil return treatment was carried out by spreading agricultural organic waste (fermented cow manure) on the soil surface (spreading amount of 800 kg / mu), followed by spraying reduction bacteria solution (spraying amount of 15 L / mu), then deep plowing to 20 cm-30 cm, ridging, and watering to maintain the field moisture content at 50%-70%, and covering with 0.02 mm thick black polyethylene film for 2 months to complete soil remediation.

[0097] The cultivation of the reducing bacterial solution includes the following steps: Desulfuric Vibrio was inoculated into Postgate medium at an 8% inoculum and cultured in a constant temperature anaerobic incubator at 37°C for 14 days.

[0098] The above-mentioned device can be used for the physicochemical remediation stage of farmland remediation. The device parameters are as follows: The vibratory pressure plate is made of 304 stainless steel and has a thickness of 12mm. The raised pressure teeth are hemispherical protrusions with a vertical length of 10 mm and a center-to-center distance of 30 mm between adjacent raised pressure teeth. The raised pressure teeth extend into the soil to be treated to a depth of 40% of the soil thickness. The vibration frequency of the vibrating pressure plate is 40Hz; the amplitude of the vibrating pressure plate is 6mm. The power of the eccentric vibration motor is 600W; the single vibration treatment time is 40min; the number of vibration treatments is 3.

[0099] Using this method to remediate farmland pollution in soil contaminated with polycyclic aromatic hydrocarbons (PAHs), after the catalytic oxidation remediation reaction was completed (i.e., testing of treatment A), the PAH degradation rate in the soil was 93% (e.g., ...). Figure 5 As shown), soluble persulfate levels rise (e.g. Figure 6 As shown). Tests conducted after soil remediation (i.e., soil testing 2 months after black polyethylene mulch covering) revealed: stable soil pH 7.5, and no excessive soluble sulfates (such as...). Figure 7 (As shown).

[0100] Example 2 A mechanically responsive piezoelectric material, differing from Example 1 in that: The mechanically responsive piezoelectric material has a particle size of 2 mm; The first raw material includes a first aluminum hydroxide pillar fluorophlogopite, persulfate (sodium persulfate), and a first inorganic binder (silica sol) in a mass ratio of 35:45:1. The coating slurry comprises a piezoelectric catalyst material in a mass ratio of 10:30:80:10, a second aluminum hydroxyl pillared fluorophlogopite, deionized water, and a second inorganic binder (silica sol). The chemical formula of the piezoelectric catalytic material is Ca 0.95 Lu0.05 Bi2Nb 1.95 Fe 0.05 O 8.975 @CeO 1.98 ; The loading of defective cerium oxide on the surface of lutetium-iron co-doped bismuth niobate calcium was 1% of the mass of lutetium-iron co-doped bismuth niobate calcium; Fluorophyllite is made of 800 mesh.

[0101] Everything else is the same as in Example 1.

[0102] The preparation method of the mechanically responsive piezoelectric material in Example 2 is the same as that in Example 1.

[0103] A method for remediating farmland pollution using mechanically responsive piezoelectric materials in conjunction with agricultural organic waste includes the following steps: Remove impurity particles with a diameter >50mm from the contaminated soil, crush the contaminated soil to a particle size of 5mm, and adjust the moisture content of the contaminated soil to 30% and the pH to 4.0 to obtain the soil to be remediated. Add the mechanically responsive piezoelectric material prepared above (0.5% of the dry weight of the soil to be remediated) to the soil to be remediated, mix (manually stir and mix) to obtain mixture A; Add persulfate solution (sodium persulfate solution, concentration 0.5 mol / L, added at 3% of the dry weight of the soil to be remediated) to mixture A to obtain mixture B; Periodic mechanical stress was applied to mixture B (the frequency of the periodic mechanical stress was 10 Hz, the amplitude was 0.5 mm, the duration of a single cycle was 20 min, and the mechanical stress was applied periodically and repeated 5 times), and then the mixture was allowed to stand for catalytic oxidation repair reaction (10 °C, 48 h) to obtain treated material A. For treatment A, soil return treatment was carried out by spreading agricultural organic waste (decomposed straw) on the soil surface (spreading amount of 1000 kg / mu), followed by spraying reduction bacteria solution (spraying amount of 20 L / mu), deep plowing to 20 cm-30 cm, ridging, and watering to maintain the field moisture content at 50%-70%. The soil was then covered with 0.02 mm thick black polyethylene film for 3 months to complete soil remediation.

[0104] The cultivation of the reducing bacterial solution includes the following steps: Desulfuric Vibrio was inoculated into Postgate medium at a 6% inoculum and cultured in a constant temperature anaerobic incubator at 37°C for 14 days.

[0105] The above-mentioned device can be used for the physicochemical remediation stage of farmland remediation. The device parameters are as follows: The vibratory pressure plate is made of 304 stainless steel and has a thickness of 12mm. The raised pressure teeth are hemispherical protrusions with a vertical length of 10 mm and a center-to-center distance of 30 mm between adjacent raised pressure teeth. The raised pressure teeth extend into the soil to be treated to a depth of 10% of the soil thickness. The vibration frequency of the vibrating pressure plate is 10Hz; the amplitude of the vibrating pressure plate is 0.5mm. The power of the eccentric vibration motor is 600W; the single vibration treatment time is 20min; and the number of vibration treatments is 5.

[0106] This method for remediating farmland pollution was used to remediate acidic chlorinated pesticide-contaminated soil. Post-remediation testing (i.e., soil testing 3 months after covering with black polyethylene film) showed that the degradation rate of chlorinated organic pollutants was 82.5%.

[0107] Example 3 A mechanically responsive piezoelectric material with a particle size of 4mm-5mm includes a core with a mass ratio of 1:1.5 and a shell covering the core.

[0108] The core is obtained by mixing and granulating the first raw material, which includes aluminum hydroxyl pillar fluorophlogopite, persulfate (ammonium persulfate) and first inorganic binder (aluminum dihydrogen phosphate) in a mass ratio of 35:45:15.

[0109] The outer shell is formed by a coating slurry, which includes a piezoelectric catalyst material in a mass ratio of 40:30:80:10, a second aluminum hydroxyl pillared fluorophlogopite, deionized water, and a second inorganic binder (aluminum dihydrogen phosphate). The piezoelectric catalyst material is lutetium-iron co-doped calcium bismuth niobate modified with defect-type cerium oxide, with the chemical formula Ca. 0.7 Lu 0.3 Bi2Nb 1.7 Fe 0.3 O 8.85 @CeO 1.65 The loading of defective cerium oxide on the surface of lutetium-iron co-doped bismuth niobate calcium is 15% of the mass of lutetium-iron co-doped bismuth niobate calcium.

[0110] Both the first and second hydroxyl aluminum-pillared fluorophlogopite were obtained by modifying fluorophlogopite (100 mesh) with a hydroxyl aluminum-pillaring solution. The hydroxyl aluminum-pillaring solution was prepared by reacting an aluminum salt solution (aluminum sulfate) with an alkaline solution (potassium hydroxide). The OH- in the alkaline solution... - With Al in aluminum salt solution 3+ The molar ratio was 1:2.8; Al in the fluorophlogopite and aluminum hydroxyl columnar liquid 3+ The mass ratio is 1:0.50.

[0111] The mechanically responsive piezoelectric material comprises, by mass fraction: 39% piezoelectric catalyst, 30% (sum of first hydroxyl aluminum-pillared fluorophlogopite and second hydroxyl aluminum-pillared fluorophlogopite), 26% persulfate, and 5% (sum of first inorganic binder and second inorganic binder).

[0112] The preparation method of this mechanically responsive piezoelectric material includes the following steps: Calcium source (calcium nitrate), lutetium source (lutetium nitrate), bismuth source (bismuth nitrate), niobium source (niobium pentoxide), and iron source (ferric nitrate) were mixed in stoichiometric ratio (molar ratio Ca:Lu:Bi:Nb:Fe=0.7:0.3:2:1.7:0.3), and molten salt medium (sodium sulfate, with the total mass of calcium source, lutetium source, bismuth source, niobium source, and iron source being in a mass ratio of 1:1.8 to the molten salt medium) was added. The mixture was then subjected to ball milling (planetary ball mill, 24 h, ball milling speed 1000 r / min), first drying (holding at 90℃ for 18 h), first calcination (holding at 950℃ for 6 h), first washing (washing with deionized water 5 times after cooling), and second drying (90℃) to obtain lutetium and iron co-doped bismuth niobate calcium. Lutetium and iron co-doped bismuth calcium niobate was dispersed in a cerium salt (cerium acetate) solution (the molar ratio of Bi in lutetium and iron co-doped bismuth calcium niobate to Ce in the cerium salt was 1:0.30). A precipitant (sodium hydroxide) was added to carry out a deposition reaction (stirring at 120℃ for 18h). After a second washing, a third drying, a second calcination (calcination at 400℃ for 5h), and a reduction treatment (heat treatment in a nitrogen-hydrogen mixed atmosphere, and heat treatment at 350℃ for 6h), a piezoelectric catalytic material was obtained. Fluorophyllite was dispersed in aluminum hydroxyl columnar liquid, and after stirring (stirring at 90℃ for 24h), aging (48h), third washing, fourth drying and activation treatment (activation at 380℃ for 8h), first aluminum hydroxyl columnar fluorophlogopite and second aluminum hydroxyl columnar fluorophlogopite were obtained. The first hydroxyl aluminum pillar fluorophlogopite was mixed with persulfate and the first inorganic binder, and then granulated (granulated at 40℃) and dried (dried at 45℃ for 48h) to obtain the core. A piezoelectric catalyst material was mixed with a second hydroxyl aluminum pillar fluorophlogopite, a second inorganic binder, and water to form a coating slurry. The coating slurry was then coated onto the surface of the core and dried (at 45°C for 48 hours) to obtain a mechanically responsive piezoelectric material.

[0113] A method for remediating farmland pollution using mechanically responsive piezoelectric materials in conjunction with agricultural organic waste includes the following steps: Remove impurity particles with a diameter >50mm from the contaminated soil, crush the contaminated soil to a particle size of 30mm, and adjust the moisture content of the contaminated soil to 85% and the pH to 3.0 to obtain the soil to be remediated. Add the mechanically responsive piezoelectric material prepared above (the amount added is 10% of the dry weight of the soil to be remediated) to the soil to be remediated, mix (stir thoroughly) to obtain mixture A; Add persulfate solution (ammonium persulfate solution, concentration 2.0 mol / L, added at 8% of the dry weight of the soil to be remediated) to mixture A to obtain mixture B; Periodic mechanical stress was applied to mixture B (the frequency of the periodic mechanical stress was 120 Hz, the amplitude was 15 mm, the duration of a single cycle was 60 min, and the mechanical stress was applied periodically and repeated 5 times), and then the mixture was allowed to stand for catalytic oxidation repair reaction (45 °C, 48 h) to obtain treated product A. For treatment A, soil return treatment was carried out by spreading agricultural organic waste (decomposed straw) on the soil surface (spreading amount of 1200 kg / mu), followed by spraying reduction bacteria solution (spraying amount of 20 L / mu), deep plowing to 20 cm-30 cm, ridging, and watering to maintain the field moisture content at 50%-70%. The soil was then covered with 0.02 mm thick black polyethylene film for 3 months to complete soil remediation.

[0114] The cultivation of the reducing bacterial solution includes the following steps: Desulfuric Vibrio was inoculated into Postgate medium at a 9% inoculum and cultured in a constant temperature anaerobic incubator at 37°C for 14 days.

[0115] The above-mentioned device can be used for the physicochemical remediation stage of farmland remediation. The device parameters are as follows: The vibratory plate is made of ceramic composite plate and has a thickness of 30mm. The raised pressure teeth are cylindrical protrusions with a vertical length of 30 mm and a center-to-center distance of 80 mm between adjacent raised pressure teeth. The raised pressure teeth extend into the soil to be treated to a depth of 80% of the soil thickness. The vibration frequency of the vibrating pressure plate is 120Hz; the amplitude of the vibrating pressure plate is 15mm. The power of the eccentric vibration motor is 1500W; the single vibration treatment time is 60min; and the number of vibration treatments is 5.

[0116] This method for remediating farmland contaminated soil with petroleum hydrocarbons was used. Post-remediation testing (i.e., soil testing 3 months after black polyethylene film covering) showed the following: petroleum hydrocarbon pollutant degradation rate of 80.2%; soil pH restored to 6.8; no excess soluble sulfate; persulfate residue below the detection limit; soil redox potential reduced to -145mV; and heavy metal leaching concentration met the agricultural land soil risk management standards.

[0117] Comparative Example 1 A soil remediation method, differing from Example 1, uses a traditional ferrous sulfate (FeSO4・7H2O)-activated sodium persulfate system as a control, with the addition amount being 0.5% of the dry weight of the soil to be remediated (equivalent to the molar amount of iron in the piezoelectric catalyst material in Example 1), and the addition amount of sodium persulfate being 3% of the dry weight of the soil to be remediated; The pH of the soil to be remediated was adjusted to 3.0 using 0.1 mol / L H2SO4.

[0118] Everything else is the same as in Example 1.

[0119] This method for remediating farmland pollution was used to remediate polycyclic aromatic hydrocarbon (PAH) contaminated soil. Post-remediation tests showed that the total PAH degradation rate was only 35.8%, and the Fe content in the soil was low. 2+ Rapid oxidation to Fe 3+ After 2 hours of reaction, the catalytic activity was basically lost, a large amount of PDS was not activated, and the residual amount reached 186 mg / kg); at the same time, the soil pH dropped to 2.6, which was severely acidified, and a large amount of iron mud (iron oxide precipitate) was produced, which blocked the soil pores.

[0120] The above description is only a preferred embodiment of this application. It should be noted that those skilled in the art can make several improvements and additions without departing from the method of this application, and these improvements and additions should also be considered within the scope of protection of this application.

Claims

1. A mechanically responsive piezoelectric material, characterized in that, It includes a core and a shell covering the core. The core is obtained by mixing and granulating a first raw material, which includes a first aluminum hydroxyl pillared fluorophlogopite, persulfate and a first inorganic binder. The outer shell is formed by a coating slurry, which includes a piezoelectric catalytic material, a second hydroxyl aluminum-pillared fluorophlogopite, water, and a second inorganic binder. The piezoelectric catalyst is lutetium niobate calcium co-doped with iron and modified with defect-type cerium oxide, with the general chemical formula Ca. 1-α Lu α Bi2Nb 2-β Fe β O 9-δ @CeO 2-x Where 0.05≤α≤0.3, 0.05≤β≤0.3, and β≥α / 2; 0.01≤δ≤0.275, and δ=β-α / 2; 0.02≤x≤0.35; Both the first hydroxyl aluminum-pillared fluorophlogopite and the second hydroxyl aluminum-pillared fluorophlogopite were obtained by modifying fluorophlogopite with hydroxyl aluminum-pillared liquid.

2. The mechanically responsive piezoelectric material according to claim 1, characterized in that, The loading of defective cerium oxide on the surface of the lutetium-iron co-doped bismuth niobate calcium is 0.5%-15% of the mass of the lutetium-iron co-doped bismuth niobate calcium.

3. The mechanically responsive piezoelectric material according to claim 1, characterized in that, The aluminum hydroxide pillar solution is prepared by reacting an aluminum salt solution with an alkaline solution, wherein the OH- in the alkaline solution... - With Al in the aluminum salt solution 3+ The molar ratio is 1:(1.5-2.8); The aluminum salt is at least one of aluminum chloride, aluminum nitrate, aluminum sulfate, and aluminum isopropoxide; The alkaline solution is at least one of sodium hydroxide, potassium hydroxide, ammonia, and sodium carbonate; The fluorophlogopite and the aluminum hydroxyl columnar liquid contain Al 3+ The mass ratio is 1:(0.02-0.50).

4. The mechanically responsive piezoelectric material according to claim 1, characterized in that, The mass ratio of the first aluminum hydroxide pillared fluorophlogopite, the persulfate and the first inorganic binder is (35-75):(10-45):(1-15); And / or, the mass ratio of the piezoelectric catalytic material, the second aluminum hydroxyl pillared fluorophlogopite, the water and the second inorganic binder is (10-40):(5-30):(30-80):(1-10); And / or, the mass ratio of the core to the shell is 1:(0.1-1.5).

5. The mechanically responsive piezoelectric material according to claim 1, characterized in that, The persulfate is at least one of sodium persulfate, potassium persulfate, and ammonium persulfate; And / or, the first inorganic binder and the second inorganic binder are both at least one of silica sol, water glass, aluminum dihydrogen phosphate, bentonite sol and kaolin sol; And / or, the particle size of the fluorophlogopite is 100-800 mesh; And / or, the particle size of the mechanically responsive piezoelectric material is 0.5 mm to 5 mm.

6. The method for preparing the mechanically responsive piezoelectric material according to any one of claims 1-5, characterized in that, Includes the following steps: A calcium source, a lutetium source, a bismuth source, a niobium source, and an iron source are mixed in stoichiometric ratios, and a molten salt medium is added. The mixture is then subjected to ball milling, a first drying, a first calcination, a first washing, and a second drying to obtain the lutetium and iron co-doped bismuth calcium niobate. The lutetium and iron co-doped bismuth calcium niobate was dispersed in a cerium salt solution, a precipitant was added to carry out a deposition reaction, and the material was obtained by a second washing, a third drying, a second calcination and reduction treatment. The fluorophlogopite was dispersed in the aluminum hydroxide pillared liquid, and after stirring, aging, third washing, fourth drying and activation treatment, the first aluminum hydroxide pillared fluorophlogopite and the second aluminum hydroxide pillared fluorophlogopite were obtained. The first aluminum hydroxide pillared fluorophlogopite was mixed with the persulfate and the first inorganic binder, and then granulated and dried to obtain the core. The piezoelectric catalytic material is mixed with the second aluminum hydroxyl pillared fluorophlogopite, the second inorganic binder and the water to form the coating slurry. The coating slurry is then coated onto the surface of the core and dried in a sixth step to obtain the mechanoresponsive piezoelectric material.

7. The method for preparing the mechanically responsive piezoelectric material according to claim 6, characterized in that, The calcium source is at least one of calcium carbonate, calcium nitrate, and calcium acetate; The lutetium source is at least one of lutetium oxide, lutetium nitrate, lutetium chloride, and lutetium acetate; The bismuth source is at least one of bismuth oxide, bismuth nitrate and bismuth citrate; The niobium source is at least one of niobium pentoxide, ammonium niobium oxalate, and niobium chloride; The iron source is at least one of iron oxide, ferric nitrate, ferric chloride, ferric acetate, and ferric oxalate. And / or, the molten salt medium is at least one of sodium chloride, potassium chloride, sodium sulfate, and a sodium chloride-potassium chloride mixed salt; the total mass ratio of the calcium source, the lutetium source, the bismuth source, the niobium source, and the iron source to the molten salt medium is 1:(1-1.8); And / or, the cerium salt is at least one of cerium nitrate, cerium chloride, cerium sulfate, and cerium acetate; the molar ratio of Bi in the lutetium-iron co-doped bismuth niobate calcium nitrate to Ce in the cerium salt is 1:(0.02-0.30); And / or, the precipitant is at least one of urea, ammonia, ammonium carbonate and sodium hydroxide.

8. The method for preparing the mechanically responsive piezoelectric material according to claim 6, characterized in that, The ball milling time is 4h-24h; the first calcination temperature is 750℃-950℃, and the first calcination time is 2h-6h; the first drying and second drying temperatures are both 50℃-90℃, and the first drying time is 4h-18h. And / or, the deposition reaction temperature is 60℃-120℃, and the deposition reaction time is 3h-18h; the second calcination temperature is 200℃-400℃, and the second calcination time is 1h-5h; the reduction treatment is performed using one of sodium borohydride solution, ascorbic acid solution, nitrogen-hydrogen mixture, or inert atmosphere heat treatment; the reduction treatment temperature is 20℃-350℃, and the reduction treatment time is 0.5h-6h; And / or, the stirring temperature is 40℃-90℃, the stirring time is 4h-24h; the aging time is 6h-48h; the activation temperature is 250℃-380℃, and the activation time is 1h-8h; And / or, the granulation temperature is 10℃-40℃; And / or, the temperature of the sixth drying is 20℃-45℃, and the time of the sixth drying is 6h-48h.

9. A method for remediating farmland pollution using a mechanically responsive piezoelectric material in conjunction with agricultural organic waste, characterized in that, Includes the following steps: Add the mechanically responsive piezoelectric material as described in any one of claims 1-5 to the soil to be remediated, mix, and obtain mixture A; Adding persulfate solution to mixture A yields mixture B; Periodic mechanical stress is applied to the mixture B, and then it is allowed to stand for a catalytic oxidation repair reaction to obtain treated product A; The treatment material A is subjected to soil return treatment. Agricultural organic waste is scattered on the soil surface, followed by spraying reduction bacteria solution, deep plowing to a depth of 20cm-30cm, ridging, watering to maintain the field moisture content at 50%-70%, and covering with black plastic film for 2-3 months to complete soil remediation. The amount of the mechanically responsive piezoelectric material added is 0.1%-10% of the dry weight of the soil to be remediated; The persulfate solution is at least one selected from sodium persulfate solution, potassium persulfate solution, and ammonium persulfate solution; the concentration of the persulfate solution is 0.01 mol / L-2.0 mol / L, and the amount of persulfate solution added is 0.05%-8% of the dry weight of the soil to be remediated; The frequency of the periodic mechanical stress is 5Hz-120Hz, the amplitude is 0.5mm-15mm, the duration of a single cycle is 5min-120min, and the mechanical stress is applied periodically 1-10 times. The catalytic oxidation repair reaction takes 0.5 h to 48 h and is carried out at a temperature of 5 °C to 45 °C. The agricultural organic waste is fermented cow manure or decomposed straw, and the amount of agricultural organic waste spread is 600 kg / mu to 1200 kg / mu. The cultivation of the reducing bacterial solution includes the following steps: Desulfuric Vibrio was inoculated into Postgate medium at an inoculation rate of 5%-10% and cultured in a constant temperature anaerobic incubator at 37℃ for 7-14 days. The spraying volume of the reducing bacterial solution is 10L / mu to 20L / mu.

10. An apparatus for carrying out the method as claimed in claim 9, characterized in that, Includes a soil treatment box, a catalyst dosing device, a persulfate dosing device, and an eccentric vibrating plate piezoelectric mechanical disturbance system; The soil treatment box is used to hold the soil to be remediated; The catalyst dosing device is used to add the mechanically responsive piezoelectric material into the soil treatment tank; The persulfate dosing device is used to add the persulfate solution into the soil treatment tank; The eccentric vibrating pressure plate piezoelectric mechanical disturbance system includes a support frame, a lifting rod, a vibrating pressure plate, an eccentric vibrating motor, and a vibration controller. The vibratory plate is positioned above the soil treatment box, and the vibratory plate is connected to the support frame via the lifting rod. The lower surface of the vibrating pressure plate is provided with raised pressure teeth, which are at least one of hemispherical, conical, strip-shaped and cylindrical protrusions; The lifting rod is used to adjust the pressing depth of the vibrating plate. As the vibrating plate presses down, the protruding pressure teeth extend into the soil to be remediated inside the soil treatment box. The eccentric vibration motor is fixed to the vibration plate, and the eccentric vibration motor is used to drive the vibration plate to perform periodic movements, thereby driving the protruding pressure teeth to apply mechanical stress to the soil to be repaired in the soil treatment box. The vibration controller is electrically connected to the eccentric vibration motor, and the vibration controller is used to adjust the vibration frequency and vibration time of the eccentric vibration motor.

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