A method for low-toxicity mercury doping of chalcogenides and regulation of transport relationships

Abstract

This invention provides a method for low-toxicity mercury doping and transport regulation of chalcogenides. The main concept involves introducing mercury doping into chalcogenide materials through spontaneous solid-state reactions at low temperatures or diffusion induced by pulsed current, using mercury sulfides as precursors. Compared with traditional methods for introducing mercury in material preparation, this invention offers advantages such as low toxicity, low reaction temperature, and precise control of Hg doping levels. It effectively regulates and optimizes carrier concentration, thermoelectric properties, and metal-insulator phase transition characteristics in material systems such as Bi0.5Sb1.5Te3, ZnS, Ag2S, NiS, TaS2, and CuIr2S4. The method provided by this invention has promising applications in temperature sensing, thermoelectric power generation, microelectronics, and semiconductors.

Description

Technical Field

[0001] This invention belongs to the field of inorganic functional materials, specifically relating to a technical method for controlling the electrical transport properties of chalcogenide functional materials by using a chalcogenide with low toxicity as a precursor and achieving mercury doping through a multi-physics field-triggered solid-phase reaction process. Background Technology

[0002] Chalcogenide functional materials play an important role and have a wide range of applications in photovoltaics [1], thermoelectrics [2,3], catalysis [4,5]. Modifying them by adjusting carrier concentration through doping or introducing a composite structure by in-situ precipitation of a nano-second phase are important methods. Among them, Hg has a rich electronic structure. Introducing mercury doping or mercury-containing second phase into the matrix of chalcogenide materials can adjust their physical properties such as carrier concentration and band gap, thereby controlling their electrical transport characteristics and optimizing the thermoelectric [6], photoelectric [7], and catalytic [8] performance of the materials. Although mercury doping of chalcogenides can achieve material modification, the difficulty of mercury doping greatly limits its research and production applications. This is because elemental mercury is a highly toxic substance and is liquid at room temperature, which is very easy to volatilize and form mercury vapor. Mercury vapor can be absorbed by the human body through the respiratory tract or skin, causing mercury poisoning and posing a great threat to human health. In addition, gaseous mercury can easily cause large-scale mercury pollution when it escapes into the environment, and even liquid mercury is difficult to collect and treat once it leaks.

[0003] Traditional methods for preparing mercury-containing materials mainly include elemental solid-state reaction methods and wet chemical reaction methods. Among these, the elemental solid-state reaction method uses elemental mercury and other elemental substances as precursors, synthesizing them under vacuum through high-temperature reactions such as melting. For example, Sn can be synthesized using elemental Sn, In, Bi, Hg, and Te. 0.98 Bi 0.02 Te-x%HgInTe2 [9]. This process usually requires high temperatures and long times, which makes elemental mercury more volatile and increases the risk of mercury vapor leakage. On the other hand, the solubility of mercury in most compounds is usually very low, and elemental mercury is highly volatile at high temperatures, making it very difficult to quantitatively dope compounds with mercury. The wet chemical reaction method uses water-soluble organic mercury salts

[10] or inorganic mercury salts

[11] as precursors to react in an aqueous solution system to prepare mercury-doped materials. Although this method can precisely control the amount of mercury doping, it is extremely easy to cause environmental pollution and thus endanger human health because the reaction involves mercury-containing solutions. At the same time, organic mercury salts are more easily absorbed by the human body than inorganic salts, and the potential harm to human health is also greater.

[0004] In summary, current mercury doping technology faces certain challenges in terms of safety, environmental friendliness, and accuracy, which limits the research and application of mercury-containing chalcogenide functional materials. Therefore, a safe, environmentally friendly, and effective method for introducing mercury doping into chalcogenide functional materials is currently lacking.

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[0011] 【6】A. Bhui, S. Das, R. Arora, U. Bhat, P. Dutta, T. Ghosh, et al. HgDoping Induced Reduction in Structural Disorder Enhances the ThermoelectricPerformance in AgSbTe2[J], Journal of the American Chemical Society, 2023,145(46):25392−25400

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[0013] 【8】H.-C. Huang, C.-L. Yang, M.-S. Wang and X.-G. Ma, Opticalabsorption enhancement of Hg-doped ZnX (X= S, Se) for hydrogen productionfrom water splitting driven by solar energy, Vacuum[J], 2018,157:36-44

[0014] 【9】X. Tan, G. Liu, J. Xu, X. Tan, H. Shao, H. Hu, et al.Thermoelectric properties of In-Hg co-doping in SnTe: Energy band engineering[J], Journal of Materiomics, 2018,4(1):62-67

[0015]

[10] J. Chen, M. Wang and X. Su, Facile preparation of red emissionHg-doped ZnSe QDs and ratiometric determination of alkaline phosphatase basedon in situ generation of dual fluorescent reporter[J], Sensors and ActuatorsB: Chemical, 2021,345:130428

[0016]

[11] R. Kosman, D. Wawrzyńczyk, M. Nyk, M. Pawlyta, O. Bezkrovnyi andB. Cichy, Zn, Cd and Hg doping of AgInS2 quantum dots – efficient strategy to modify nonlinear absorption[J], Journal of Materials Chemistry C, 2023,11(31): 10758-10769 Summary of the Invention

[0017] This invention provides a method for low-toxicity mercury doping and transport regulation of chalcogenides. The main concept involves using mercury sulfides as precursors to introduce mercury doping into chalcogenide materials through a solid-state reaction at a relatively low temperature. Compared with traditional techniques for introducing mercury in material preparation, this invention offers advantages such as low toxicity, low reaction temperature, and precise control of Hg doping levels. It effectively achieves low-toxicity mercury doping of Bi... 0.5 Sb 1.5 Carrier concentration, thermoelectric properties, and metallic insulator properties of material systems such as Te3, ZnS, Ag2S, NiS, TaS2, and CuIr2S4.

[0018] Adjustment and optimization of phase transition characteristics. The method provided by this invention has promising applications in temperature sensing, thermoelectric power generation, microelectronics and semiconductors.

[0019] A method for low-toxicity mercury doping of chalcogenides and regulation of transport relationships, which mainly includes the following steps:

[0020] 1) Based on the chalcogenide composition to be doped or composited and the functional characteristics to be achieved, select the chalcogenide parent material and mercury sulfide as precursors, and determine the mixing ratio of the precursors according to the amount of mercury doping to be achieved, and fully mix the chalcogenide parent material powder with the precursors.

[0021] 2) Based on the chalcogenide parent material and the desired doping concentration, select a specific temperature and pressure, and under vacuum or inert gas atmosphere, utilize low-temperature self-propagating reaction or diffusion induced by pulsed current to achieve uniform diffusion of mercury between the low-toxicity precursor and the parent material, while simultaneously sintering the material to achieve density. Select an appropriate cooling rate based on the precipitation method of the mercury-containing second phase.

[0022] 3) Based on the actual application requirements of the device, the prepared materials are processed at low temperatures to avoid mercury precipitation. Further introduction of electrodes or other functional material modules can then create thermoelectric devices, temperature and pressure sensors, optoelectronic devices, etc.

[0023] Furthermore, the chemical formula of the chalcogenide functional material described in step 1) is AB. y Where A is a metallic element, including one or more of the following elements: V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Ag, Cd, In, Sn, Sb, Ta, W, Ir, Pb, and Bi; B is a chalcogenide element, including one or more of the following: S, Se, and Te; and y ranges from 0.5 to 3.5 depending on the valence of the metallic element. The chemical composition of the mercury chalcogenide is HgX, where X is a single chalcogenide element S, Se, or Te, or a combination of multiple chalcogenide elements. Regarding the total amount of mercury sulfide added, if the goal is only to regulate its properties through doping, the added mercury content should not exceed the solid solubility limit of mercury in the chalcogenide matrix; if the goal is to regulate the electrical conductivity, thermal conductivity, and other properties of the material through in-situ precipitation of a mercury-containing second phase, the added mercury content should exceed the solid solubility limit of mercury in the chalcogenide matrix. Regarding the types of mercury chalcogenides added, without introducing new chalcogenide anion substitution, one or more of the chalcogenide anions present in the raw material of the chalcogenide functional material are selected as the anions to avoid introducing new anion doping; alternatively, chalcogenide element substitution can be achieved simultaneously with the introduction of mercury doping by selecting mercury precursors containing different chalcogenides. In Example 1, for Bi... 0.5 Sb 1.5 When doping Te3 with mercury, HgTe is selected as the dopant. In Example 21, when doping ZnSe with mercury, HgSe is selected as the dopant. When it is desirable to introduce new types of chalcogenide anions, one or more chalcogenide anions not present in the chalcogenide functional material matrix should be selected as the anion. Different types of chalcogenide anions can have different regulatory effects, and by precisely controlling the chalcogenide anions in the mercury-doped chalcogenide functional material, the performance of the mercury-doped chalcogenide functional material can be precisely controlled. In Example 10, HgTe is selected as the dopant to dope Ag2S, thereby reducing its phase transition temperature; in Example 11, equal amounts of HgS and HgTe are used as dopant. While maintaining the same mercury doping amount, the phase transition temperature is controllably adjusted by regulating the relative content of different chalcogenide anions.

[0024] Further, the self-propagating reaction initiation temperature in step 2) is 50 ℃-1000 ℃, and the inert gas or vacuum atmosphere includes nitrogen, helium, argon, corresponding chalcogenide vapors, and a vacuum atmosphere, wherein the vacuum atmosphere pressure is less than 10 Pa to avoid oxidation during material sintering and to prevent the decomposition of HgS under oxygen-containing atmosphere heating. The holding time is 0.5-240 hours. In Example 1, Bi... 0.5 Sb 1.5 When introducing HgTe doping into Te3, spark plasma sintering was used, followed by holding at 430 °C under vacuum for 20 minutes. In Example 9, when introducing HgS doping into Ag2S, the temperature was maintained at 300 °C under vacuum for 24 hours.

[0025] Further, in step 2), if the sintering process described can be performed by cold-pressing the chalcogenide matrix into a block, then sintering can be carried out under vacuum or an inert gas atmosphere after cold pressing. This utilizes the spontaneous diffusion reaction of the material at low temperatures to sinter into a dense, uniform block. The sintering temperature is 200℃-1000℃, and the holding time is 0.5-24 hours. If the chalcogenide matrix has poor formability and cannot be cold-pressed into a block, or if it is desirable to introduce anisotropy into the matrix, then pressure sintering should be used, simultaneously inducing the diffusion of mercury atoms between the materials using pulsed current. The sintering temperature should be 0.6-0.8 times the melting point of the chalcogenide functional material, provided it does not exceed the maximum reaction temperature mentioned above. Excessively high sintering temperatures will lead to grain growth and a decrease in mechanical properties; excessively low temperatures will result in a slow diffusion rate, leading to insufficient material density or uneven distribution of Hg. The sintering pressure should be 40-60 MPa. Insufficient sintering pressure will cause a decrease in material density, thus affecting its performance. The sintering time is 5-50 minutes. The pressure sintering process may introduce strong texture into the material, resulting in differences in performance between the directions parallel and perpendicular to the pressure. These directions should be strictly distinguished during material testing and application, and the direction with superior performance should be selected. In Example 1, HgTe with a stoichiometric ratio of 0.0125 was used to sinter Bi. 0.5 Sb 1.5 When doping with Te3, a discharge plasma sintering process was performed at 430 °C and 50 MPa for 20 min to obtain a uniform and dense mercury-doped Bi. 0.5 Sb 1.5 The ZT value of Te3 thermoelectric material reaches a maximum of 0.78 at 125 ℃ when parallel to the pressure direction, while its ZT value perpendicular to the pressure direction only reaches 0.62 at 125 ℃.

[0026] Further, the selection of a suitable cooling rate mentioned in step 2) refers to the ability to control the precipitation of a mercury-containing second phase by slow or rapid cooling when the mercury doping concentration is close to the solid solubility limit of mercury in a chalcogenide matrix. In-situ precipitation of a mercury-containing second phase can adjust the material's basic electrical and thermal conductivity. Rapid cooling is beneficial for enhancing the solid solubility tendency of mercury in the matrix, with a cooling rate of 1-5 °C / min; while slow cooling is beneficial for enhancing the tendency of the mercury-containing compound as a second phase to precipitate in situ in the matrix, with a cooling rate of 10-50 °C / min. In Example 4, Bi... 0.5 Sb 1.5 Excessive HgTe was doped into the Te3 matrix, and the HgTe second phase was precipitated in situ by slow cooling, thereby achieving the regulation of the electrical transport properties.

[0027] Furthermore, in step 3), the cold working process should be carried out with sufficient cooling medium such as water or oil to avoid local temperature rise of the workpiece causing the mercury element dissolved in the chalcogenide functional material to precipitate as a second phase, thereby causing its electrical, thermal or other physical properties to deviate from the expected values.

[0028] Furthermore, this method is applicable to introducing mercury doping into bismuth telluride-based thermoelectric materials, thereby adjusting the carrier concentration of the matrix thermoelectric material, optimizing thermoelectric performance, effectively shifting its ZT peak to a higher temperature, and ensuring that its thermoelectric performance does not deteriorate significantly over a wide temperature range above room temperature. It can be applied to the field of wide temperature difference power generation at room temperature and above.

[0029] Furthermore, this method is applicable to introducing mercury doping into chalcogenide electronic phase transition materials, including Ag₂S, TaS₂, NiS, and CuIr₂S₄ systems. Mercury doping enables quantitative control of their transport relationships and phase transition properties.

[0030] Furthermore, this method is applicable to introducing mercury doping into chalcogenide optoelectronic semiconductor materials, including ZnS, ZnSe, and ZnTe systems. Mercury doping allows for the adjustment of their band gap and transport relationships, making them suitable for various optical and electronic device applications.

[0031] This invention relates to a method for low-toxicity mercury doping of chalcogenides and the regulation of transport relationships. Compared with traditional semiconductor doping processes, this method uses mercury chalcogenides as the mercury source, achieving mercury doping or the introduction of a mercury-containing second phase at a lower temperature. This significantly reduces the toxicity of the mercury precursor used and the doping process, thereby greatly reducing the potential harm of mercury to humans and the environment. Simultaneously, it precisely controls the amount of mercury doping, ultimately achieving regulation of the electrical transport properties of chalcogenide functional materials. Using the mercury doping method provided by this invention, the thermoelectric properties of metal chalcogenides and the phase transition properties of metal insulators can be adjusted and optimized under relatively safe conditions, showing broad application prospects in temperature sensors, thermoelectric power generation, energy conversion, microelectronics, and artificial intelligence. Compared with previously reported mercury doping methods, Attached Figure Description

[0032] Figure 1 Bi prepared using the mercury doping method proposed in this invention 0.5 Sb 1.5 The X-ray diffraction pattern of the Te3-0.0125HgTe thermoelectric material shows that the prepared material is a single phase.

[0033] Figure 2 Bi prepared using the mercury doping method proposed in this invention 0.5 Sb 1.5 The X-ray diffraction pattern of the Te3-0.1HgTe thermoelectric material shows that, since the maximum solid solubility of mercury has been exceeded, the prepared material contains a second phase of HgTe.

[0034] Figure 3 Bi prepared using the method described in this invention 0.5 Sb 1.5 The conductivity of each component sample of the Te3-xHgTe thermoelectric material parallel to the direction of spark plasma sintering pressure is as follows. It can be seen that the conductivity of each sample decreases with increasing temperature, and mercury doping can effectively modulate the conductivity of Bi. 0.5 Sb 1.5 Electrical conductivity of Te3-based thermoelectric materials.

[0035] Figure 4 Bi prepared using the method described in this invention 0.5 Sb 1.5 The Seebeck coefficients of the Te3-xHgTe thermoelectric material samples are parallel to the direction of spark sintering pressure in the discharge plasma. It can be seen that the Seebeck coefficients of the doped samples all increase with increasing temperature, indicating that mercury doping suppresses the Bi... 0.5 Sb 1.5 Intrinsic excitation of Te3.

[0036] Figure 5Bi prepared using the method described in this invention 0.5 Sb 1.5 The power factor of each component sample of the Te3-xHgTe thermoelectric material parallel to the direction of discharge plasma spark sintering pressure.

[0037] Figure 6 Bi prepared using the method described in this invention 0.5 Sb 1.5 The thermal conductivity of each component sample of the Te3-xHgTe thermoelectric material parallel to the direction of spark sintering pressure during discharge plasma sintering. It can be seen that trace amounts of mercury doping can suppress bipolar thermal conductivity, thereby suppressing the overall thermal conductivity.

[0038] Figure 7 Bi prepared using the method described in this invention 0.5 Sb 1.5 ZT plots of Te3-xHgTe thermoelectric material samples parallel to the direction of spark plasma sintering pressure. It can be seen that the ZT value of the HgTe-doped sample reaches a maximum of 0.78 at 125 °C, and remains above 0.6 in the range of 25 °C-200 °C.

[0039] Figure 8 The figure shows the temperature-resistivity relationship of the mercury-doped Ag₂S electronic phase transition material prepared using the method described in this invention. It can be seen that after HgS doping, the phase transition temperature of Ag₂S shifts slightly to a lower temperature, and its resistivity before and after the phase transition is significantly higher than that without doping, indicating that HgS doping effectively regulates the phase transition characteristics and transport relationships of Ag₂S.

[0040] Figure 9 The figure shows the temperature-resistivity relationship of the mercury-doped CuIr₂S₄ electronic phase transition material prepared using the method described in this invention. It can be seen that after HgS doping, the fundamental resistivity of CuIr₂S₄ increases by nearly an order of magnitude, effectively controlling its transport properties. Detailed Implementation

[0041] Unless otherwise specified, all raw materials used in this invention can be obtained commercially available or prepared according to conventional methods in the art. Unless otherwise defined or stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of skill in the art. Furthermore, any methods and materials similar to or equivalent to those described herein may be applied to the methods of this invention.

[0042] Other aspects of the invention will be apparent to those skilled in the art from the disclosure herein.

[0043] The present invention will be further illustrated 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 invention. Experimental methods in the following embodiments, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer.

[0044] Example 1: Bi 0.5 Sb 1.5 The Te3 crystal rod was crushed, poured into an agate mortar and ground into powder, then passed through a 200-mesh sieve. The sieved Bi... 0.5 Sb 1.5 Te3 powder and high-purity HgTe were weighed in a molar ratio of 1:0.0125 and ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were added to both ends of the graphite mold in sequence. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 430 °C under an axial pressure of 50 MPa and held for 20 minutes, then cooled to room temperature at a rate of 5 °C / min. After the sample cooled, it was removed, the surface carbon paper was peeled off, and the sample, now sintered into a dense block, was polished with 1000-grit sandpaper until the surface was smooth, completely removing any remaining carbon paper, thus obtaining Bi with an HgTe doping content of 1.25%. 0.5 Sb 1.5 Te3-based thermoelectric materials. The doped Bi... 0.5 Sb 1.5 Te3-based thermoelectric materials were used as p-type thermoelectric legs, employing doped Bi2Te 2.7 Se 0.3 By using the basic thermoelectric material as an n-type leg and introducing electrodes, a high-performance thermoelectric device can be assembled, which is suitable for thermoelectric power generation applications in a wide temperature range of room temperature and above.

[0045] Example 2: Bi 0.5 Sb 1.5 The Te3 crystal rod was crushed, poured into an agate mortar and ground into powder, then passed through a 200-mesh sieve. The sieved Bi... 0.5 Sb 1.5Te3 powder and high-purity HgTe were weighed in a molar ratio of 1:0.025 and ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were added sequentially to both ends of the graphite mold. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 430 °C under an axial pressure of 50 MPa and held for 20 minutes, then cooled to room temperature at a rate of 5 °C / min. After the sample cooled, it was removed, the surface carbon paper was peeled off, and the sample, now sintered into a dense block, was polished with 1000-grit sandpaper until the surface was smooth, completely removing any remaining carbon paper, thus obtaining Bi with an HgTe doping content of 2.5%. 0.5 Sb 1.5 Te3-based thermoelectric materials. The doped Bi... 0.5 Sb 1.5 Te3-based thermoelectric materials were used as p-type thermoelectric legs, employing doped Bi2Te 2.7 Se 0.3 By using the basic thermoelectric material as an n-type leg and introducing electrodes, a thermoelectric device can be assembled, which is suitable for thermoelectric power generation applications in a wide temperature range of room temperature and above.

[0046] Example 3: Bi 0.5 Sb 1.5 The Te3 crystal rod was crushed, poured into an agate mortar and ground into powder, then passed through a 200-mesh sieve. The sieved Bi... 0.5 Sb 1.5 Te3 powder and high-purity HgTe were weighed in a molar ratio of 1:0.05 and ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were added to both ends of the graphite mold in sequence. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 430 °C under an axial pressure of 50 MPa and held for 20 minutes, then cooled to room temperature at a cooling rate of 5 °C / min. After the sample cooled, it was removed, the surface carbon paper was peeled off, and the sample, now sintered into a dense block, was polished with 1000-grit sandpaper until the surface was smooth, completely removing any remaining carbon paper, thus obtaining Bi with 5% HgTe doping. 0.5 Sb 1.5 Te3-based thermoelectric materials. The doped Bi... 0.5 Sb 1.5Te3-based thermoelectric materials were used as p-type thermoelectric legs, employing doped Bi2Te 2.7 Se 0.3 By using the basic thermoelectric material as an n-type leg and introducing electrodes, a thermoelectric device can be assembled, which is suitable for thermoelectric power generation applications in a wide temperature range of room temperature and above.

[0047] Example 4: Bi 0.5 Sb 1.5 The Te3 crystal rod was crushed, poured into an agate mortar and ground into powder, then passed through a 200-mesh sieve. The sieved Bi... 0.5 Sb 1.5 Te3 powder and high-purity HgTe were weighed in a molar ratio of 1:0.1 and ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were added to both ends of the graphite mold in sequence. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 430 °C under an axial pressure of 50 MPa and held for 20 minutes, then cooled to room temperature at a rate of 5 °C / min. After the sample cooled, it was removed, the surface carbon paper was peeled off, and the sample, now sintered into a dense block, was polished with 1000-grit sandpaper until the surface was smooth, completely removing any remaining carbon paper, thus obtaining Bi with 10% HgTe doping. 0.5 Sb 1.5 Te3-based thermoelectric materials. Their X-ray diffraction pattern is attached. Figure 2 As shown, this indicates that the sample contains the HgTe second phase. The doped Bi... 0.5 Sb 1.5 Te3-based thermoelectric materials were used as p-type thermoelectric legs, employing doped Bi2Te 2.7 Se 0.3 By using the basic thermoelectric material as an n-type leg and introducing electrodes, a thermoelectric device can be assembled, which is suitable for thermoelectric power generation applications in a wide temperature range of room temperature and above.

[0048] Example 5: Bi2Te 2.7 Se 0.3 The crystal rod was crushed, poured into an agate mortar and ground into powder, then passed through a 200-mesh sieve. The sieved Bi2Te... 2.7 Se 0.3Powdered and high-purity HgTe were weighed at a molar ratio of 1:0.0125 and ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete adhesion to the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were added sequentially to both ends of the graphite mold. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 430 °C under an axial pressure of 50 MPa and held for 20 minutes, then cooled to room temperature at a rate of 5 °C / min. After the sample cooled, it was removed, the surface carbon paper was peeled off, and the sample, now sintered into a dense block, was polished with 1000-grit sandpaper until the surface was smooth, completely removing any remaining carbon paper. This yielded Bi₂Te with an HgTe doping content of 1.25%. 2.7 Se 0.3 Thermoelectric materials. The doped Bi₂Te 2.7 Se 0.3 Bi-doped thermoelectric material is used as the n-type thermoelectric leg. 0.5 Sb 1.5 Te3-based thermoelectric materials can be used as p-type legs and introduced into electrodes to assemble thermoelectric devices, which are suitable for thermoelectric power generation applications in a wide temperature range of room temperature and above.

[0049] Example 6: Bi2Te 2.7 Se 0.3 The crystal rod was crushed, poured into an agate mortar and ground into powder, then passed through a 200-mesh sieve. The sieved Bi2Te... 2.7 Se 0.3 Powdered and high-purity HgSe were weighed at a molar ratio of 1:0.0125 and ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were added sequentially to both ends of the graphite mold. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 430 °C under an axial pressure of 50 MPa and held for 20 minutes, then cooled to room temperature at a rate of 5 °C / min. After the sample cooled, it was removed, the surface carbon paper was peeled off, and the sample, now sintered into a dense block, was polished with 1000-grit sandpaper until the surface was smooth, completely removing any remaining carbon paper. This yielded Bi₂Te with an HgSe doping content of 1.25%. 2.7 Se 0.3 Thermoelectric materials. The doped Bi₂Te 2.7 Se 0.3Bi-doped thermoelectric material is used as the n-type thermoelectric leg. 0.5 Sb 1.5 Te3-based thermoelectric materials can be used as p-type legs and introduced into electrodes to assemble thermoelectric devices, which are suitable for thermoelectric power generation applications in a wide temperature range of room temperature and above.

[0050] Example 7: Bi2Te 2.7 Se 0.3 The crystal rod was crushed, poured into an agate mortar, and ground into powder, then passed through a 200-mesh sieve. According to Bi2Te... 2.7 Se 0.3 Weigh the materials according to the molar ratio of HgTe:HgSe = 1:0.00625:0.00625, pour the mixture into an agate mortar, and grind it evenly. Roll carbon paper into a cylindrical shape and place it inside a graphite mold with a diameter of 10 mm, ensuring it adheres completely to the inner wall of the mold. Pour the evenly mixed raw material powder into the carbon paper, tap it to compact it, and flatten it with a pressure head. Add conductive carbon paper and graphite gaskets to both ends of the graphite mold in sequence. Place the assembled mold into the reaction chamber of a spark plasma sintering device, use a mechanical pump to evacuate the reaction chamber to a vacuum of 20 Pa, and then begin heating. Raise the temperature to 430 °C under an axial pressure of 50 MPa and hold for 20 minutes, then cool to room temperature at a cooling rate of 5 °C / min. After the sample cooled, it was removed, the carbon paper on its surface was peeled off, and the sample, which had been sintered into a dense block, was polished with 1000-grit sandpaper until the surface was smooth. All residual carbon paper was then removed, yielding Bi₂Te with 0.625% HgTe and 0.625% HgSe doping. 2.7 Se 0.3 Thermoelectric materials. The doped Bi₂Te 2.7 Se 0.3 Bi-doped thermoelectric material is used as the n-type thermoelectric leg. 0.5 Sb 1.5 Te3-based thermoelectric materials can be used as p-type legs and introduced into electrodes to assemble thermoelectric devices, which are suitable for thermoelectric power generation applications in a wide temperature range of room temperature and above.

[0051] Example 8: Ag₂S powder was sieved through a 200-mesh sieve and weighed according to the Ag₂S:HgS molar ratio of 0.95:0.05. The powder was then ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were then added to both ends of the graphite mold. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 300 °C under an axial pressure of 50 MPa and held for 20 minutes, then cooled to room temperature at a rate of 5 °C / min. After the sample has cooled, remove it, peel off the carbon paper from its surface, and use 1000-grit sandpaper to polish the sample, which has been sintered into a dense block, until the surface is smooth and all residual carbon paper is completely removed, thus obtaining the sample with the chemical formula Ag. 1.9 Hg 0.05 S is a silver-based chalcogenide sensitive resistor material. Further introduction of electrodes allows it to be fabricated into a temperature and pressure sensor, suitable for applications such as marine electric field temperature and pressure sensing and temperature and pressure alarms.

[0052] Example 9: Ag₂S powder was passed through a 200-mesh sieve and weighed according to the Ag₂S:HgS molar ratio of 0.9:0.1. It was then ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were added to both ends of the graphite mold in sequence. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 300 °C under an axial pressure of 50 MPa and held for 20 minutes, then cooled to room temperature at a rate of 5 °C / min. After the sample cooled, it was removed, the surface carbon paper was peeled off, and the sample, now sintered into a dense block, was polished with 1000-mesh sandpaper until the surface was smooth, completely removing any remaining carbon paper. This yielded the sample with the chemical formula Ag. 1.8 Hg 0.1 S is a silver-based chalcogenide sensitive resistor material. Further introduction of electrodes allows it to be fabricated into a temperature and pressure sensor, suitable for applications such as marine electric field temperature and pressure sensing and temperature and pressure alarms.

[0053] Example 10: Ag₂S powder was passed through a 200-mesh sieve and weighed according to the molar ratio of Ag₂S:HgTe = 0.9:0.1. The powder was then ground evenly in an agate mortar. The powder was poured into a 10 mm diameter tableting mold and cold-pressed into a block under a pressure of 10 MPa. The block was then sealed in a vacuum quartz tube and placed in a muffle furnace. The temperature was raised to 200 °C for 20 minutes, then raised to 300 °C for another 20 minutes, and held at 300 °C for 24 hours. Finally, it was slowly cooled to room temperature at a cooling rate of 5 °C / min to obtain the product with the chemical formula Ag₂S. 1.8 Hg 0.1 S 0.9 Te 0.1 The silver-based chalcogenide sensitive resistor material can be further processed into a temperature and pressure sensor by introducing electrodes, suitable for applications such as marine electric field temperature and pressure sensing and temperature and pressure alarm.

[0054] Example 11: Ag₂S powder was passed through a 200-mesh sieve and weighed according to the molar ratio of Ag₂S:HgS:HgTe = 0.9:0.05:0.05. The powder was then poured into an agate mortar and ground evenly. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were then added to both ends of the graphite mold. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 300 °C under an axial pressure of 50 MPa and held for 20 minutes, then cooled to room temperature at a cooling rate of 5 °C / min. After the sample has cooled, remove it, peel off the carbon paper from its surface, and use 1000-grit sandpaper to polish the sample, which has been sintered into a dense block, until the surface is smooth and all residual carbon paper is completely removed, thus obtaining the sample with the chemical formula Ag. 1.8 Hg 0.1 S 0.95 Te 0.05 The silver-based chalcogenide sensitive resistor material can be further processed into a temperature and pressure sensor by introducing electrodes, suitable for applications such as marine electric field temperature and pressure sensing and temperature and pressure alarm.

[0055] Example 12: Ag2S 0.5 Te 0.5 The powder passes through a 200-mesh sieve, according to Ag2S 0.5 Te 0.5Weigh out HgTe in a molar ratio of 0.8:0.2 and grind it evenly in an agate mortar. Pour the powder into a 10 mm diameter tableting mold and cold-press it into a block under a pressure of 10 MPa. Then, seal the block in a vacuum quartz tube and place it in a muffle furnace. Raise the temperature to 200 °C for 20 minutes, then raise it to 300 °C for another 20 minutes, hold it at that temperature for 24 hours, and finally slowly cool it to room temperature at a cooling rate of 5 °C / min to obtain Ag. 1.6 Hg 0.2 S 0.4 Te 0.6 The silver-based chalcogenide sensitive resistor material can be further processed into a temperature and pressure sensor by introducing electrodes, suitable for applications such as marine electric field temperature and pressure sensing and temperature and pressure alarm.

[0056] Example 13: TaS2 powder was passed through a 200-mesh sieve and weighed according to the molar ratio of TaS2:HgS = 0.95:0.1. The powder was then ground evenly in an agate mortar. The powder was poured into a 10 mm diameter tableting mold and cold-pressed into a block under a pressure of 10 MPa. The block was then sealed in a vacuum quartz tube and placed in a quenching furnace. The temperature was raised to 200 °C for 20 minutes, then raised to 500 °C for 60 minutes and held at 500 °C for 24 hours. The temperature was then raised to 800 °C for 60 minutes and held for 12 hours. Finally, the mixture was water-quenched and cooled to room temperature to obtain the product with the chemical formula Ta. 0.95 Hg 0.1 S is an electronic phase change material with a 1T-TaS2 phase structure. Further introduction of electrodes allows it to be fabricated into a thermistor device, suitable for applications such as temperature sensing below room temperature.

[0057] Example 14: TaS2 powder was passed through a 200-mesh sieve and weighed according to a molar ratio of TaS2:HgS = 0.9:0.2. The powder was then ground evenly in an agate mortar. The powder was poured into a 10mm diameter tableting mold and cold-pressed into a block under a pressure of 10 MPa. The block was then sealed in a vacuum quartz tube and placed in a quenching furnace. The temperature was raised to 200°C in 20 minutes, then raised to 500°C in 60 minutes and held at 500°C for 24 hours. The temperature was then raised to 800°C in 60 minutes and held for 12 hours. Finally, the mixture was water-quenched and cooled to room temperature to obtain the product with the chemical formula Ta. 0.9 Hg 0.2 S is an electronic phase change material with a 1T-TaS2 phase structure. Further introduction of electrodes allows it to be fabricated into a thermistor device, suitable for applications such as temperature sensing below room temperature.

[0058] Example 15: TaS2 powder was passed through a 200-mesh sieve and weighed according to a molar ratio of TaS2:HgS = 0.95:0.1. The powder was then ground evenly in an agate mortar. The powder was poured into a 10 mm diameter tableting mold and cold-pressed into a block under a pressure of 10 MPa. The block was then sealed in a vacuum quartz tube and placed in a muffle furnace. The temperature was raised to 200 °C over 20 minutes, then raised to 500 °C over 60 minutes, and held at 500 °C for 24 hours. Finally, it was slowly cooled to room temperature at a cooling rate of 5 °C / min to obtain 2H-Ta. 0.95 Hg 0.1 S material.

[0059] Example 16: TaS2 powder was passed through a 200-mesh sieve and weighed according to a molar ratio of TaS2:HgS = 0.9:0.2. The powder was then ground evenly in an agate mortar. The powder was poured into a 10 mm diameter tableting mold and cold-pressed into a block under a pressure of 10 MPa. The block was then sealed in a vacuum quartz tube and placed in a muffle furnace. The temperature was raised to 200 °C over 20 minutes, then raised to 500 °C over 60 minutes, and held at 500 °C for 24 hours. Finally, it was slowly cooled to room temperature at a cooling rate of 5 °C / min to obtain 2H-Ta. 0.9 Hg 0.2 S material.

[0060] Example 17: CuIr2S4 powder was sieved through a 200-mesh sieve and weighed according to a CuIr2S4:HgS molar ratio of 1:0.025. The powder was then ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were then added to both ends of the graphite mold. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 430 °C under an axial pressure of 50 MPa and held for 20 minutes. Finally, it was slowly cooled to room temperature at a cooling rate of 5 °C / min. After the sample has cooled, it is removed, the carbon paper on its surface is peeled off, and the sample, which has been sintered into a dense block, is polished with 1000-grit sandpaper until the surface is smooth. The residual carbon paper on its surface is completely removed, thus obtaining CuIr2S4 phase change material with a mercury doping content of 2.5%.

[0061] Example 18: CuIr2S4 powder was passed through a 200-mesh sieve and weighed according to a CuIr2S4:HgS molar ratio of 1:0.05. The powder was then ground evenly in an agate mortar. The powder was poured into a 10 mm diameter pressing mold and cold-pressed into a block under a pressure of 10 MPa. The block was then sealed in a vacuum quartz tube and placed in a muffle furnace. The temperature was raised to 200 °C over 20 minutes, then raised to 500 °C over 60 minutes, and held at 500 °C for 24 hours. Finally, it was slowly cooled to room temperature at a cooling rate of 5 °C / min to obtain a CuIr2S4 phase change material with 5% mercury doping.

[0062] Example 19: NiS powder was passed through a 200-mesh sieve and weighed according to the molar ratio of NiS:HgSe = 0.95:0.05. The powder was then ground evenly in an agate mortar. The powder was poured into a 10 mm diameter tablet mold and cold-pressed into a block under a pressure of 10 MPa. The block was then sealed in a vacuum quartz tube and placed in a muffle furnace. The temperature was raised to 400 °C after 200 minutes and held at 400 °C for 24 hours. After another 100 minutes, the temperature was raised to 700 °C and held for 24 hours. Finally, the mixture was water-quenched to room temperature to obtain β-Ni. 0.95 Hg 0.05 S 0.95 Se 0.05 Phase change materials.

[0063] Example 20: ZnS powder was passed through a 200-mesh sieve and weighed according to a ZnS:HgS molar ratio of 0.95:0.05. The powder was then ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were then added to both ends of the graphite mold. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 500 °C under an axial pressure of 50 MPa and held for 20 minutes. Finally, the temperature was slowly cooled to room temperature at a cooling rate of 5 °C / min. After the sample has cooled, remove it, peel off the carbon paper from its surface, and use 1000-grit sandpaper to polish the sample, which has been sintered into a dense block, until the surface is smooth and all residual carbon paper is completely removed, thus obtaining the sample with the chemical formula Zn. 0.95 Hg 0.05 S-type optoelectronic semiconductor materials.

[0064] Example 21: ZnSe powder was passed through a 200-mesh sieve and weighed according to a ZnSe:HgSe molar ratio of 0.95:0.05. The powder was then ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were then added to both ends of the graphite mold. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 500 °C under an axial pressure of 50 MPa and held for 20 minutes. Finally, the temperature was slowly cooled to room temperature at a cooling rate of 5 °C / min. After the sample has cooled, remove it, peel off the carbon paper from its surface, and use 1000-grit sandpaper to polish the sample, which has been sintered into a dense block, until the surface is smooth and all residual carbon paper is completely removed, thus obtaining the sample with the chemical formula Zn. 0.95 Hg 0.05 Se is a photoelectric semiconductor material.

[0065] Example 22: ZnTe powder was sieved through a 200-mesh sieve and weighed according to a molar ratio of ZnTe:HgTe = 0.9:0.1. It was then ground evenly in an agate mortar. Carbon paper was rolled into a cylindrical shape and placed inside a 10 mm diameter graphite mold, ensuring complete contact with the mold's inner wall. The evenly mixed raw material powder was poured into the carbon paper, compacted, and flattened with a pressure head. Conductive carbon paper and graphite gaskets were added to both ends of the graphite mold in sequence. The assembled mold was placed in the reaction chamber of a spark plasma sintering apparatus. A mechanical pump was used to evacuate the reaction chamber to a vacuum of 20 Pa, followed by heating. The temperature was raised to 850 °C under an axial pressure of 50 MPa and held for 20 minutes. Finally, it was slowly cooled to room temperature at a cooling rate of 5 °C / min. After the sample cooled, it was removed, the surface carbon paper was peeled off, and the sample, now sintered into a dense block, was polished with 1000-mesh sandpaper until the surface was smooth, completely removing any remaining carbon paper, thus obtaining ZnTe. 0.9 Hg 0.1 Te's optoelectronic semiconductor materials.

[0066] Example 23: ZnSe powder was passed through a 200-mesh sieve and weighed according to a ZnSe:HgSe molar ratio of 0.9:0.1. The powder was then ground evenly in an agate mortar. The powder was poured into a 10 mm diameter tableting mold and cold-pressed into a block under a pressure of 10 MPa. The block was then sealed in a vacuum quartz tube and placed in a muffle furnace. The temperature was raised to 200 °C over 20 minutes, then raised to 500 °C over 60 minutes, and held at 500 °C for 24 hours. Finally, it was slowly cooled to room temperature at a cooling rate of 5 °C / min to obtain ZnSe. 0.9 Hg 0.1 Se optoelectronic semiconductor materials.

[0067] Example 24: Using ZnS 0.5 Se 0.5 The powder passes through a 200-mesh sieve, according to ZnS 0.5 Se 0.5 Weigh out HgS at a molar ratio of 0.8:0.2 and grind it evenly in an agate mortar. Pour the powder into a 10 mm diameter tableting mold and cold-press it into a block under a pressure of 10 MPa. Then, seal the block in a vacuum quartz tube and place it in a muffle furnace. Raise the temperature to 200 °C for 20 minutes, then raise it to 500 °C for 60 minutes, and hold it at 500 °C for 24 hours. Finally, slowly cool it to room temperature at a cooling rate of 5 °C / min to obtain Zn. 0.8 Hg 0.2 S 0.6 Se 0.4 Optoelectronic semiconductor materials.

[0068] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the substantive technical content of the present invention. The substantive technical content of the present invention is broadly defined within the scope of the claims. Any technical entity or method completed by others that is completely identical to or an equivalent modification of the claims is considered to be covered within the scope of the claims.

Claims

1. A method for low-toxicity mercury doping of chalcogenides and regulation of transport relationships, characterized in that, The main steps include: 1) Based on the chalcogenide composition to be doped or composited and the functional characteristics to be achieved, select undoped chalcogenides and mercury sulfides as precursors, and determine the mixing ratio of the precursors according to the amount of mercury doping to be achieved, and fully mix the chalcogenide parent material powder with the precursors. 2) Based on the chalcogenide parent material, select a certain temperature and pressure, and under vacuum or inert gas atmosphere, utilize low-temperature self-propagating reaction or diffusion induced by pulsed current to achieve uniform diffusion of mercury between the low-toxicity precursor and the parent material, while sintering the material to make it dense; select an appropriate cooling rate based on the precipitation mode of the mercury-containing second phase. 3) Based on the actual application requirements of the device, the prepared materials are processed at low temperature to avoid mercury precipitation; by further introducing electrodes or other functional material modules, thermoelectric material devices, temperature and pressure sensor devices, and optoelectronic material devices can be prepared. The chemical formula of the chalcogenide functional material is AB. y Where A is a metallic element, including one or more of the following elements: V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Ag, Cd, In, Sn, Sb, Ta, W, Ir, Pb, and Bi; B is a chalcogenide element, including one or more of the following elements: S, Se, and Te; the value of y ranges from 0.5 to 3.5 depending on the valence of the metallic element; the chemical composition of the mercury chalcogenide compound is HgX, where X is a single chalcogenide element S, Se, or Te, or a combination of multiple chalcogenide elements; Step 2) The low-temperature self-propagating reaction temperature is 50°C-1000°C, and the inert gas or vacuum atmosphere includes nitrogen, helium, argon and vacuum atmosphere, wherein the vacuum atmosphere pressure is less than 10Pa to avoid oxidation during the sintering process of the material, and also to avoid the decomposition of HgS when heated in an oxygen-containing atmosphere; the holding time is 0.5-240 hours. When the mercury doping concentration is close to the solid solubility limit of mercury in a chalcogenide matrix, the precipitation of the mercury-containing second phase can be controlled by slow or fast cooling. In-situ precipitation of the mercury-containing second phase can adjust the physical properties of the material's basic electrical and thermal conductivity. Fast cooling is beneficial to enhance the solid solubility tendency of mercury in the matrix, with a cooling rate of 1-5°C / min; while slow cooling is beneficial to enhance the tendency of the mercury-containing compound as a second phase to precipitate in situ in the matrix, with a cooling rate of 10-50°C / min.

2. The method for low-toxicity mercury doping and transport regulation of chalcogenides as described in claim 1, characterized in that, Regarding the total amount of mercury sulfides added, if the goal is only to regulate performance through doping, the added mercury content should not exceed the solid solubility limit of mercury in the chalcogenide matrix. If the goal is to regulate the electrical and thermal conductivity of the material through in-situ precipitation of a mercury-containing second phase, the added mercury content should exceed the solid solubility limit of mercury in the chalcogenide matrix. Regarding the types of mercury chalcogenides added, if it is not desired to introduce new types of chalcogenide anions, one or more of the chalcogenide anions present in the raw materials of the chalcogenide functional material should be selected as the anions to avoid introducing new anion doping. If it is desired to introduce new types of chalcogenide anions, one or more of the chalcogenide anions not present in the chalcogenide functional material matrix should be selected as the anions. Different types of chalcogenide anions can have different regulatory effects, and through precise regulation of chalcogenide anions in mercury-doped chalcogenide functional materials, precise regulation of the performance of mercury-doped chalcogenide functional materials can be achieved.

3. The method for low-toxicity mercury doping and transport regulation of chalcogenides as described in claim 1, characterized in that, In step 2), if the sintering process described above can be cold-pressed into blocks and anisotropy is not desired, then cold pressing followed by sintering in a vacuum or inert gas atmosphere should be used. This utilizes the spontaneous diffusion of the material at low temperatures to sinter into a dense, uniform block. The sintering temperature is 200°C-1000°C, and the holding time is 0.5-24 hours. If the chalcogenide material matrix has poor formability and cannot be cold-pressed into blocks, or if anisotropy is desired to be introduced into the matrix, then pressure-induced pulsed current should be used to induce the diffusion of mercury atoms between the materials. The sintering temperature should be 0.6-0.8 times the melting point of the chalcogenide functional material, provided it does not exceed the maximum reaction temperature. Excessive sintering temperature will lead to grain growth and a decrease in mechanical properties; excessively low temperature will result in a slow diffusion rate, leading to insufficient material density or uneven Hg distribution. The sintering pressure should be 40-60 MPa; insufficient pressure will reduce material density and affect its performance. The sintering time should be 5-50 minutes. Pressure sintering may introduce strong texture into the material, causing differences in performance between directions parallel and perpendicular to the pressure. During material testing and application, the direction should be strictly distinguished, and the direction with better performance should be selected for application.

4. The method for low-toxicity mercury doping and transport regulation of chalcogenides as described in claim 1, characterized in that, The aforementioned low-temperature processing should employ water or oil cooling media for sufficient cooling to prevent localized temperature increases in the workpiece from causing the mercury element dissolved in the chalcogenide functional material to precipitate as a second phase, thereby causing its electrical, thermal, or other physical properties to deviate from expectations.

5. The method for low-toxicity mercury doping and transport relationship regulation of chalcogenides as described in claim 1, characterized in that, Introducing mercury doping into bismuth telluride-based thermoelectric materials can adjust the carrier concentration of the matrix thermoelectric material, optimize its thermoelectric performance, effectively shift its ZT peak to a higher temperature, and its thermoelectric performance does not deteriorate significantly in a wide temperature range above room temperature. It can be applied to the field of wide temperature difference power generation at room temperature and above.

6. The method for low-toxicity mercury doping and transport regulation of chalcogenides as described in claim 1, characterized in that, The method involves introducing mercury doping into chalcogenide electronic phase transition materials, including Ag2S, TaS2, NiS, and CuIr2S4 systems. Mercury doping enables quantitative control of their transport relationships and phase transition properties.

7. The method for low-toxicity mercury doping and transport relationship regulation of chalcogenides as described in claim 1, characterized in that, The present invention pertains to the introduction of mercury doping into chalcogenide optoelectronic semiconductor materials, including ZnS, ZnSe, and ZnTe. Mercury doping can adjust the band gap to make them suitable for optical and electronic device applications in different scenarios.

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