A metastable phase rare earth nickel-based oxide hydrogen-induced electronic phase transition dynamics regulation method

Abstract

A kind of metastable phase rare earth nickel-based oxide hydrogen-induced electronic phase transition dynamics regulation method belongs to material science and electronic information field.Specific metal electrode is contacted with rare earth nickel-based oxide material with controllable shape, and is placed in acidic chemical environment, based on the difference between the work function of metal and rare earth nickel-based oxide material, transfer of hydrogen ion in chemical environment is driven, to realize the electronic configuration of rare earth nickel-based oxide material by controllable rate from the transition of three-valence nickel dominated delocalized electronic structure to divalent nickel dominated localized electronic structure, and trigger the increase of material resistivity at controllable rate;When specific metal electrode is contacted with rare earth nickel-based oxide material with controllable shape, and is placed in alkaline chemical environment, it will trigger the sharp decrease of material resistivity.The present application has high safety, low cost and energy saving;It can accurately control the degree and rate of hydrogen-induced phase transition to realize the detection of different acid-base concentration chemical environment.

Description

Technical Field

[0001] This invention belongs to the fields of materials science and electronic information, and specifically relates to a kinetic control method for the degree and rate of hydrogen-induced electronic phase transition of rare earth nickel-based oxides by comprehensively designing the work function difference between rare earth nickel-based oxides and metals and the pH value of the solution. Background Technology

[0002] Rare earth nickel-based perovskite oxides are typical strongly correlated semiconductors in a thermodynamically metastable phase structure. Their chemical formula is usually represented by ReNiO3 (Re = Rare earth, Re ≠ La). They exhibit typical metallic insulating phase transition transport characteristics, meaning that when the temperature rises to a certain critical value, they transform from an insulating phase to a metallic phase [Nat. Commun., 2014, 5, 4860; Appl. Phys. Lett., 2015, 107, 031905; Phys. Rev. Lett., 1999, 82, 3871; Phys. Rev. B, 2004, 69, 153105; Phase Transitions, 2008, 81, 729]. This characteristic makes the material a promising candidate for applications in fields such as abrupt change thermistors [Adv. Funct. Mater., 2020, 30, 2000987], infrared camouflage [Proc. Natl. Acad. Sci., 2019, 116, 26402], and solid oxide fuel cells [Nature, 2016, 534, 231].

[0003] Besides its temperature-induced metallic insulating phase transition properties, another characteristic of rare-earth nickel-based perovskite oxide materials is their rapid and reversible hydrogen-induced phase transition properties [Nat. Commun., 2014, 5, 4860]. This is characterized by the reversible doping of hydrogen with a platinum catalyst, which transforms the material's original electron-traveling orbital configuration based on +3 valence nickel into an electron-localized orbital configuration based on +2 valence nickel, triggering a sudden change in resistance or resistivity. These properties can be achieved by annealing rare-earth nickel-based oxides in a hydrogen atmosphere, or by triggering them with an electric field in an electrochemical solution environment.

[0004] The main process of hydrogen-induced phase transition is as follows: First, a noble metal such as Pt of a certain shape is grown on a rare-earth nickel-based oxide thin film material; second, a sudden change in resistivity can be achieved by reacting at a certain temperature, such as 300℃, and at a low hydrogen concentration (such as 5%) for a certain period of time; finally, the reverse process is generally carried out in an oxygen atmosphere. The hydrogen-induced electronic phase transition characteristics of rare-earth nickel-based oxides have important application value in fields such as non-volatile biomimetic neural networks [Nat. Commun., 2017, 8, 240], synaptic transistors [Nat. Commun., 2013, 4, 2676], and biomass sensing [Nat. Commun., 2019, 10, 1651]. Furthermore, hole-doped rare-earth nickel-based oxide materials such as Nd... 0.8 Sr 0.2 NiO3 and other materials were placed in a closed environment with a certain amount of CaH2 solid and reacted at a certain temperature for a certain time. After that, electrical transport tests were performed, and superconductivity was achieved at a certain temperature [Nature, 2019, 572, 624]. This property can also be regarded as a hydrogen-induced phase transition.

[0005] While hydrogen-induced phase transitions (HPTs) play a crucial role in regulating the electrical transport properties of rare-earth nickel-based oxides (REEs) and hold broad application prospects, the currently available two triggering methods for HPTs in REEs struggle to achieve precise control over the dynamics of the HPT electronic phase transition. For example, both hydrogen-induced phase transitions triggered by hydrogen annealing and electric fields in electrochemical solutions fail to allow for accurate design and control of the rate of change in hydrogen resistance. Exploring novel triggering methods for precisely controlling HPTs in metastable, strongly correlated quantum materials and achieving accurate control over the electronic phase transition dynamics will further expand the applications of these materials in other fields, such as human health monitoring, acid and alkali gas monitoring, and monitoring of the acidity and alkalinity of industrial wastewater. Summary of the Invention

[0006] This invention mainly relates to a method for regulating the kinetic characteristics of the degree and rate of hydrogen-induced electronic phase transition of rare earth nickel-based oxides by comprehensively designing the work function difference between metastable rare earth nickel-based oxides and metals and the pH value of the solution.

[0007] The present invention regulates the hydrogen-induced electronic phase transition of rare-earth nickel-based oxides by bringing a metal electrode into contact with the rare-earth nickel-based oxides and placing them in an acidic or alkaline chemical environment. On the one hand, by reasonably matching the work functions of the metal electrode and the rare-earth nickel-based oxides and selecting the degree of the acidic or alkaline chemical environment, precise design of the degree and rate of the hydrogen-induced electronic phase transition of the rare-earth nickel-based oxides is achieved, enabling their application in fields such as brain-like computing and bionic nerves. On the other hand, based on the variation law of the hydrogen-induced electronic phase transition characteristics of the metal electrode and the rare-earth nickel-based oxides in chemical environments with different pH values, detection of the acidity and alkalinity in chemical environments such as solutions, gases, and atomized atmospheres can be realized.

[0008] A method for regulating the kinetics of hydrogen-induced electronic phase transition of metastable rare-earth nickel-based oxides. A specific metal electrode is brought into contact with the rare-earth nickel-based oxide material in a controllable shape and placed in an acidic chemical environment. Based on the difference in work functions between the metal and the rare-earth nickel-based oxide material, hydrogen ions in the chemical environment are driven to transfer, thereby enabling the electronic configuration of the rare-earth nickel-based oxide material to change from a itinerant electron structure dominated by trivalent nickel to a localized electron structure dominated by divalent nickel at a controllable rate, and triggering the resistivity of the material to increase at a controllable rate. The realization methods of this controllability include changes in rare-earth elements, electrode types, electrode shapes, and pH values. When a specific metal electrode is brought into contact with the rare-earth nickel-based oxide material in a controllable shape and placed in an alkaline chemical environment, a sharp decrease in the resistivity of the material will be triggered.

[0009] This hydrogen-induced electronic phase transition process can be further precisely regulated by applying an electric field; this new method for triggering hydrogen-induced phase transition can achieve precise design of the degree and rate of the hydrogen-induced electronic phase transition of rare-earth nickel-based oxides and detection of acidic or alkaline chemical environments.

[0010] Furthermore, the crystal structure of the rare-earth nickel-based perovskite oxide material is a perovskite structure of ABO3: The A site is a single rare-earth element or a combination of multiple rare-earth elements with rare-earth elements, preferably dysprosium: Dy, erbium: Er, ytterbium: Yb, samarium: Sm, neodymium: Nd, europium: Eu, praseodymium: Pr, lanthanum: La, samarium neodymium: Sm x Nd 1-x , where 0 < x < 1, samarium praseodymium: Sm x Pr 1-x , where 0 < x < 1, europium neodymium: Eu x Nd 1-x , where 0 < x < 1, europium praseodymium: Eu x Pr 1-x , where 0 < x < 1; The B site is a single nickel element or a combination of nickel and other transition metals, preferably nickel: Ni, nickel strontium: Ni x Sr 1-x , where 0 < x < 1, nickel manganese: Nix Mn 1-x , where 0 < x < 1, nickel-zinc: Ni x Zn 1-x , where 0 < x < 1, nickel-cobalt: Ni x Co 1-x , where 0 < x < 1, nickel-iron: Ni x Fe 1-x , where 0 < x < 1, nickel-copper: Ni x Cu 1-x , where 0 < x < 1, nickel-vanadium: Ni x V 1-x , where 0 < x < 1. Further, the rare earth nickel-based perovskite oxide includes various different forms, rare earth nickel-based perovskite oxide powder, rare earth nickel-based perovskite oxide nanowire, rare earth nickel-based perovskite oxide thin film, rare earth nickel-based perovskite oxide ceramic. In a preferred example, by changing the rare earth element, the rate of hydrogen-induced phase change is changed; in a preferred example, by changing the form of the rare earth nickel-based perovskite oxide, the rate of hydrogen-induced phase change is changed; in another preferred example, by doping the B-site element, the rate of hydrogen-induced phase change is changed.

[0011] Further, the selected metal electrode needs to meet the following conditions: 1) The work function of the metal electrode and the rare earth nickel-based oxide material has a certain match. When the work functions of the metal electrode and the rare earth nickel-based oxide material are close, preferably the difference is within 0.1 eV. The rate of the method for triggering hydrogen-induced phase change provided by the present invention is slow. As the work function difference between the metal electrode and the rare earth nickel-based oxide material increases, the rate of the method for triggering hydrogen-induced phase change provided by the present invention increases;

[0012] 2) The metal electrode will not form a passivation film on the surface of the metal electrode in an acidic or alkaline chemical environment. Under the condition of meeting the above two conditions, when the pH value is between 0 and 14, preferably Cu, Ni, Zn, Al, Ag, Fe, Co, Pt, Pd, Mn, Ti, Cr, Ta, W. In a preferred example, the work function of the Pt metal electrode is close to that of the rare earth nickel-based oxide, preferably the difference is within 0.1 eV, and the rate of hydrogen-induced phase change is slow; in a preferred example, the work function of the Cu metal electrode differs from that of the rare earth nickel-based oxide by about 0.8 eV, and the rate of hydrogen-induced phase change is greater than that of the Pt metal electrode; in another preferred example, the work function of the Zn metal electrode differs from that of the rare earth nickel-based oxide by more than 1 eV, and the rate of hydrogen-induced phase change is greater than that of the Cu metal electrode.

[0013] Furthermore, the shape of the metal electrode can be divided into discontinuous and continuous shapes. The size and spacing of the discontinuous array metal electrode can vary from micrometers to millimeters. The shapes of the discontinuous array metal electrode include: arrayed dots, strips, triangles, squares, pentagons, and hexagons. The continuous metal electrode has a size at the millimeter level or larger. Continuous metal electrodes continuously cover a portion of the film surface without forming an array distribution structure, and include circular, rectangular, square, triangular, pentagonal, and hexagonal shapes. The contact methods between the rare-earth nickel-based perovskite oxide and the metal electrode mainly include two forms: first, the metal electrode is placed on the rare-earth nickel-based perovskite oxide, which is simple to operate and usually separable; second, the metal electrode is deposited on the rare-earth nickel-based perovskite oxide by magnetron sputtering or vapor deposition, which is generally difficult to separate from the rare-earth nickel-based perovskite oxide. In a preferred embodiment, a discontinuous array metal electrode is used; in another preferred embodiment, a continuous metal electrode is used.

[0014] Furthermore, the acidic or alkaline chemical environment includes both solution and aerosol environments: Acidic or alkaline chemical solution environments include: 1) Acid solutions: such as hydrochloric acid, acetic acid, oxalic acid, and sulfuric acid; 2) Acidic salt solutions: such as sodium bicarbonate, calcium bicarbonate, sodium bisulfate, and sodium hydrosulfide; 3) Alkaline solutions: such as sodium hydroxide, potassium hydroxide, and ammonia. Acidic or alkaline aerosol environments include: 1) Acidic aerosol environments: hydrogen chloride, hydrogen sulfide, sulfur dioxide, sulfur trioxide, carbon dioxide, nitrogen dioxide, and chlorine; 2) Alkaline aerosol environments: ammonia, hydrazine, and phosphine. Unless otherwise specified, the pH value of the above acidic or alkaline aerosol environments is between 0 and 14. In one preferred embodiment, the rate of hydrogen-induced phase transition of metastable rare-earth nickel-based oxides is controlled in an acidic chemical solution environment; in another preferred embodiment, changing the pH value of the acidic chemical solution will change the rate of hydrogen-induced phase transition of metastable rare-earth nickel-based oxides; in yet another preferred embodiment, the rate of hydrogen-induced phase transition of metastable rare-earth nickel-based oxides is controlled in an alkaline chemical solution environment; in yet another preferred embodiment, the rate of hydrogen-induced phase transition of metastable rare-earth nickel-based oxides is controlled in an acidic aerosol environment; in yet another preferred embodiment, the rate of hydrogen-induced phase transition of metastable rare-earth nickel-based oxides is controlled in an alkaline aerosol environment.

[0015] Furthermore, the kinetics of the hydrogen-induced electronic phase transition in metastable rare-earth nickel-based oxides can be further controlled in terms of rate and reversibility via an electric field. Applying a negative electric field or a pulsed electric field to the rare-earth nickel-based oxide accelerates the hydrogen-induced phase transition rate; applying a positive electric field or a pulsed electric field slows down the hydrogen-induced phase transition rate. Adjusting the voltage allows for the control of accelerating or inhibiting the hydrogen-induced phase transition rate; the minimum applied voltage is in the millivolt range, and the maximum voltage generally does not exceed one hundred volts. In one preferred embodiment, the rate at which the hydrogen-induced phase transition is triggered is controlled by the sign of the applied voltage; in another preferred embodiment, the rate at which the hydrogen-induced phase transition is triggered is controlled by changing the magnitude of the voltage.

[0016] The application of the kinetic regulation of hydrogen-induced electronic phase transitions in metastable rare-earth nickel-based oxides, as described above, is characterized by two aspects: Firstly, by utilizing a reasonable match between the work function of the metal electrode and the rare-earth nickel-based oxide, preferably with a difference within 0.1 eV, and combining this with the selection of the acidity or alkalinity of the chemical environment, the degree and rate of hydrogen-induced electronic phase transitions in rare-earth nickel-based oxides can be precisely designed. The regulation range of the hydrogen-induced phase transition rate is from 0.001 times per minute to 1,000,000 times per minute, thereby assisting its application in fields such as brain-like computing and bionic neural networks. Secondly, based on the changing characteristics of hydrogen-induced electronic phase transitions of the metal electrode and the rare-earth nickel-based oxide in chemical environments with different pH values, chemical environments with different acid and alkaline concentrations can be detected. In one preferred example, the hydrogen-induced phase transition rate was approximately 0.004 times per minute within 15 minutes; in another preferred example, an increase of more than 260,000 times per minute in the hydrogen-induced phase transition rate was achieved within 45 minutes.

[0017] Through extensive and in-depth research, the inventors have designed a method for the kinetic control of hydrogen-induced electronic phase transitions in metastable rare-earth nickel-based oxides. The main concept lies in utilizing the synergistic effect of the work function difference between rare-earth nickel-based perovskite oxides and metal electrodes, and the pH value of the chemical environment, to achieve precise kinetic control of the degree and rate of hydrogen-induced electronic phase transitions in rare-earth nickel-based oxides. By contacting a metal electrode of a specific shape and size with the rare-earth nickel-based oxide and placing it in an acidic chemical environment, the difference in work function between the metal and the rare-earth nickel-based oxide drives the transfer of hydrogen ions in the solution. This causes the electronic configuration of the rare-earth nickel-based oxide material to transition at a certain rate from a trivalent nickel-dominated itinerant electronic structure to a divalent nickel-dominated localized electronic structure, triggering a sharp increase in the material's resistivity. Conversely, when a specific metal electrode is contacted with the rare-earth nickel-based oxide material in a controllable shape and placed in an alkaline chemical environment, a sharp decrease in the material's resistivity is triggered. This process can also be combined with an external electric field to accelerate or reverse the hydrogen-induced electronic phase transition process of rare-earth nickel-based oxides, further enabling precise control of the hydrogen-induced phase transition rate of rare-earth nickel-based perovskite oxides. This new hydrogen-induced phase transition triggering method not only allows for precise design of the degree and rate of hydrogen-induced electronic phase transitions in rare-earth nickel-based oxides, but also enables the detection of chemical environments with different pH values.

[0018] Compared to traditional methods that utilize precious metals Pt or Pd annealing at high temperatures in hydrogen or applying an electric field in an electrolyte solution to achieve hydrogen-induced phase transitions, the hydrogen-induced phase transition triggering technology and method provided by this invention requires no hydrogen atmosphere, thus ensuring high safety; it eliminates the need for precious metals, resulting in low cost; and it eliminates the need for adding or applying an electric field. Furthermore, by designing the work function of the metal electrode and selecting an acidic or alkaline chemical environment to synergistically trigger the hydrogen-induced phase transition of rare-earth nickel-based oxides, the invention offers the ability to precisely control the degree and rate of the hydrogen-induced phase transition, further expanding the application of rare-earth nickel-based oxides in the detection of acidic or alkaline chemical solutions and the monitoring of acidic and alkaline gases. Attached Figure Description

[0019] Figure 1 The resistance of Cu and SmNiO3 films in contact in a 0.05 mol / L oxalic acid solution changes over time, where R0 is the initial resistance of the SmNiO3 film.

[0020] Figure 2 The resistance of Cu and NdNiO3 films in contact in a 0.05 mol / L oxalic acid solution changes over time, where R0 is the initial resistance of the NdNiO3 film.

[0021] Figure 3 The resistance of Pt and SmNiO3 films in contact in a 0.05 mol / L oxalic acid solution changes over time, where R0 is the initial resistance of the SmNiO3 film.

[0022] Figure 4 The resistance of Zn and SmNiO3 films in contact in a 0.05 mol / L oxalic acid solution changes over time, where R0 is the initial resistance of the SmNiO3 film.

[0023] Figure 5 The resistance of Zn and NdNiO3 films in contact in a 0.05 mol / L oxalic acid solution changes over time, where R0 is the initial resistance of the NdNiO3 film.

[0024] Figure 6 The resistance of Zn and SmNiO3 films in contact in a 0.05 mol / L potassium hydroxide solution changes over time, where R0 is the initial resistance of the SmNiO3 film.

[0025] Figure 7 The resistance of Cu and NdNiO3 films in a 0.005 mol / L oxalic acid solution changes over time, where R0 is the initial resistance of the NdNiO3 film. Detailed Implementation

[0026] Unless otherwise specified, all raw materials used in this invention are 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.

[0027] Other aspects of the invention will be apparent to those skilled in the art from the disclosure herein.

[0028] 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.

[0029] Test Method: We used a 4200 semiconductor characterization system to measure and characterize the resistance of rare-earth nickel-based oxides. The characterization method was performed according to generally accepted standards in the art.

[0030] Example 1:

[0031] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the SmNiO3 film was contacted with a metallic Cu phase and placed in a 0.05 mol / L oxalic acid solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 film was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. The above process was repeated to obtain the change of the resistance ratio over time, as shown below. Figure 1 As shown, the resistance ratio increases by 1.06 times within 15 minutes, 1.81 times within 30 minutes, 4.65 times within 45 minutes, 9.20 times within 60 minutes, and 5657.45 times within 75 minutes, indicating that the hydrogen-induced phase transition rate gradually increases.

[0032] Example 2:

[0033] NdNiO3 thin films were selected as the research object. The resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the NdNiO3 film was contacted with a Cu metallic phase and placed in a 0.05 mol / L oxalic acid solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The resistance or resistivity of the NdNiO3 film was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. The above process can be repeated to obtain the change of the resistance ratio over time, such as... Figure 2 As shown, the resistance ratio increases by 10.38 times in 15 minutes, 13.63 times in 30 minutes, 146.42 times in 45 minutes, and by 3.64 × 10⁻⁶ in 60 minutes. 7 The resistivity of NdNiO3 increased more over time compared to the graph in Example 1, indicating that changes in rare earth ions can regulate the rate of hydrogen-induced phase transition.

[0034] Example 3:

[0035] SmNiO3 ceramic was selected as the research object. The resistance or resistivity of the ceramic material before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the SmNiO3 ceramic was contacted with the Cu metallic phase and placed in a 0.05 mol / L oxalic acid solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 ceramic was measured again. The ratio of the obtained resistance to the initial resistance was used. An increase in the ratio indicates that the SmNiO3 ceramic has undergone a hydrogen-induced electronic phase transition. An increase in the ratio with time indicates an increase in the rate of the hydrogen-induced phase transition. Compared with Example 1, the faster the rate of increase in the ratio with time, the faster the rate of the hydrogen-induced phase transition.

[0036] Example 4:

[0037] SmNi was selected 0.5 Cu 0.5 Using O3 thin films as the research object, the resistance or resistivity of the thin films before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, SmNi... 0.5 Cu 0.5 An O3 thin film was brought into contact with metallic Cu and placed in a 0.05 mol / L oxalic acid solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The SmNi was then measured again. 0.5 Cu 0.5 The ratio of the resistance or resistivity of the O3 thin film to its initial resistance or resistivity increases significantly over time, indicating that the synergistic effect of the work function difference between the rare earth nickel-based perovskite oxide and the metal electrode, as well as the pH value of the chemical environment, can trigger the SmNi... 0.5 Cu 0.5 The hydrogen-induced phase transition of O3 thin films was observed, and the faster the ratio increased, the faster the hydrogen-induced phase transition rate. Compared with Example 1, rare earth nickel-based oxides with a faster ratio increase within the same time period indicated a faster hydrogen-induced phase transition rate.

[0038] Example 5:

[0039] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the SmNiO3 film was brought into contact with a Pt metal phase and placed in a 0.05 mol / L oxalic acid solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 film was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. The above process was repeated to obtain the change of the resistance ratio over time, as shown below. Figure 3 As shown, the resistance ratio increases by a factor of 0.99 within 15 minutes, a factor of 1.05 within 30 minutes, a factor of 1.13 within 45 minutes, and a factor of 1.31 within 60 minutes. The change in resistance ratio over time is not significant, indicating that a hydrogen-induced phase transition hardly occurs. Compared to Example 1, the rate at which Pt is used as the metal electrode to trigger a hydrogen-induced phase transition is very low within the same time frame.

[0040] Example 6:

[0041] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the SmNiO3 film was contacted with a metallic Zn phase and placed in a 0.05 mol / L oxalic acid solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 film was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. This process can be repeated to obtain the change in the resistance ratio over time, such as... Figure 4 As shown, the resistance ratio increased by 1.28 times within 15 minutes, 23.19 times within 30 minutes, 155.31 times within 45 minutes, and 1,659,844.27 times within 60 minutes. The hydrogen-induced phase transition rate increased with time. Comparing with the figure in Example 1, it can be found that when Zn metal is selected as the electrode, the resistance ratio of the SmNiO3 film changes more in the same time period, indicating that the hydrogen-induced phase transition rate of the SmNiO3 film triggered by the Zn metal electrode is faster. This shows that different metal electrodes can be selected to control the different hydrogen-induced phase transition rates of rare earth nickel-based perovskite oxide materials.

[0042] Example 7:

[0043] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, arrays of circular and triangular Cu metal electrodes were deposited on two SmNiO3 films, respectively. The diameter and spacing of the circular Cu metal electrodes were both 100 μm, while the length and spacing of the triangular Cu metal electrodes were both 100 μm. The samples were then placed in a 0.05 mol / L oxalic acid solution for a period of time, removed, rinsed with deionized water, and dried. The resistance or resistivity of the two SmNiO3 films was then measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. The process could be repeated to obtain the change in the resistance ratio over time. Comparison revealed that both circular and triangular Cu metal electrode arrays increased the resistance ratio of the SmNiO3 film over time, indicating that different shaped metal electrodes can trigger the hydrogen-induced electronic phase transition in the SmNiO3 film, and the rate of the hydrogen-induced phase transition increases with time.

[0044] Example 8:

[0045] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, a 1 mm x 1 mm rectangular continuous Cu metal electrode was deposited on the SmNiO3 film and placed in a 0.05 mol / L oxalic acid solution for a period of time. The samples were then removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 film was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time on the abscissa. The above process could be repeated to obtain the change of the resistance ratio over time. The resistance ratio of the SmNiO3 film increased with time, indicating that the continuous rectangular Cu metal electrode can trigger the hydrogen-induced electronic phase transition of the SmNiO3 film under these conditions, and the hydrogen-induced phase transition rate increases with time. However, compared with the array-type Cu metal electrode in Example 7, the hydrogen-induced phase transition rate is smaller.

[0046] Example 9:

[0047] NdNiO3 thin films were selected as the research object. The resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the NdNiO3 film was contacted with a metallic Zn phase and placed in a 0.05 mol / L oxalic acid solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The resistance or resistivity of the NdNiO3 film was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. The above process can be repeated to obtain the change of the resistance ratio over time, such as... Figure 4 As shown, the resistance ratio increases with time. Within 15 minutes, the resistance ratio increases by 146.57 times; within 30 minutes, it increases by 2,064,772.13 times; and within 45 minutes, it increases by 1.19 × 10⁻⁶ times. 7 The result shows that the hydrogen-induced phase transition rate increases with time. Furthermore, a comparison with the results in Example 2 clearly shows that the metal Zn electrode causes a faster increase in the resistivity ratio of the NdNiO3 film within the same time period, indicating that the hydrogen-induced electronic phase transition rate is faster at this time.

[0048] Example 10:

[0049] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, two SmNiO3 films were contacted with metallic Al phases and placed in aerosol environments containing 15% sulfur dioxide and carbon dioxide, respectively. After a period of time, the samples were removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 films was then measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. The above process could be repeated to obtain the change of the resistance ratio over time. In both cases, the resistance ratio of the SmNiO3 films increased with time, but the resistivity of the SmNiO3 films in the sulfur dioxide aerosol environment increased faster, indicating that the hydrogen-induced electronic phase transition rate of the SmNiO3 films was faster in this case. This further proves that SmNiO3 films can be used for the detection of acidic aerosol chemical environments.

[0050] Example 11:

[0051] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the SmNiO3 film was contacted with a metallic Zn phase and placed in a 0.05 mol / L potassium hydroxide solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 film was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. This process can be repeated to obtain the change in the resistance ratio over time, such as... Figure 6 As shown, the resistance ratio decreases over time. Within 15 minutes, the resistance decreases to 0.98 times the initial resistance; within 30 minutes, it decreases to 0.96 times the initial resistance; within 45 minutes, it decreases to 0.92 times the initial resistance; within 60 minutes, it decreases to 0.57 times the initial resistance; and within 75 minutes, it decreases to 0.50 times the initial resistance. After that, the resistance remains unchanged from 90 to 120 minutes. This indicates that the hydrogen-induced electronic phase transition of the SmNiO3 film is suppressed under alkaline conditions.

[0052] Example 12:

[0053] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, two SmNiO3 films were contacted with a metallic Al phase and placed in a 15% ammonia aerosol environment for a period of time. The samples were then removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 films was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time on the abscissa. The above process could be repeated to obtain the change in the resistance ratio over time. The resistance ratio of the SmNiO3 films decreased over time, indicating that the hydrogen-induced electronic phase transition of the SmNiO3 films was suppressed, further demonstrating that SmNiO3 films can be used for the detection of alkaline aerosol chemical environments.

[0054] Example 13:

[0055] NdNiO3 thin films were selected as the research object. The resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the NdNiO3 film was contacted with a Cu phase and placed in a 0.005 mol / L oxalic acid solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The resistance or resistivity of the NdNiO3 film was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. The above process can be repeated to obtain the change of the resistance ratio over time, such as... Figure 7 As shown, the resistance ratio increases by a factor of 1.23 within 15 minutes, 9.87 times within 30 minutes, 6478.63 times within 45 minutes, 8328 times within 60 minutes, 112347.62 times within 75 minutes, 87305.77 times within 90 minutes, and 543275.51 times within 105 minutes. Comparing this with the results in Example 2, it can be found that under the same conditions, the hydrogen-induced electronic phase transition rate varies with different pH values, indicating that pH can regulate the hydrogen-induced electronic phase transition rate of the NdNiO3 thin film.

[0056] Example 14:

[0057] NdNiO3 thin films were selected as the research object. The resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the NdNiO3 film was contacted with a Cu phase and placed in a 0.0005 mol / L oxalic acid solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The resistance or resistivity of the NdNiO3 film was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. The above process could be repeated to obtain the change of the resistance ratio over time. The resistance ratio increased with increasing time. Comparing with the results in Example 2, it can be found that under the same conditions, the hydrogen-induced electronic phase transition rate differs with different pH values, indicating that pH value can regulate the hydrogen-induced electronic phase transition rate of the NdNiO3 film.

[0058] Example 15:

[0059] Select Sm 0.5 Nd 0.5 Using NiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, Sm... 0.5 Nd 0.5 A NiO3 thin film was brought into contact with metallic Cu and placed in a 0.05 mol / L oxalic acid solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The Sm value was then measured again. 0.5 Nd 0.5 The ratio of the resistance or resistivity of the NiO3 thin film to its initial resistance or resistivity increases significantly over time, indicating that the synergistic effect of the work function difference between the rare earth nickel-based perovskite oxide and the metal electrode, as well as the pH value of the chemical environment, can trigger Sm 0.5 Nd 0.5 The hydrogen-induced phase transition of NiO3 thin films was observed, and compared with Example 1, the faster the resistance ratio increased, the faster the hydrogen-induced phase transition rate was.

[0060] Example 16:

[0061] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the SmNiO3 film was contacted with a Cu phase and placed in a 0.05 mol / L sulfuric acid solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 film was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time on the abscissa. The above process could be repeated to obtain the change in the resistance ratio over time. The increase in the resistance ratio over time indicates that the SmNiO3 film underwent a hydrogen-induced electronic phase transition. Compared with Example 1, it can be found that the hydrogen-induced electronic phase transition rate was faster within the same time frame.

[0062] Example 17:

[0063] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the SmNiO3 film was contacted with a Cu phase and placed in a 0.05 mol / L oxalic acid solution. A negative potential of -0.1 V was applied to the SmNiO3 film, and after a period of time, the sample was removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 film was then measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. Comparing the results with those of Example 1, it can be found that the rate of increase in the resistance ratio is significantly increased when a negative electric field is applied to the SmNiO3 film, indicating that applying an electric field can further accelerate the hydrogen-induced electronic phase transition rate of the SmNiO3 film.

[0064] Example 18:

[0065] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the SmNiO3 film was contacted with a Cu phase and placed in a 0.05 mol / L oxalic acid solution. A positive potential of 0.1 V was applied to the SmNiO3 film, and after a period of time, the sample was removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 film was then measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. Comparing the results with those of Example 1, it can be found that the rate of increase in the resistance ratio is significantly slower when a positive electric field is applied to the SmNiO3 film, indicating that applying an electric field can further suppress the hydrogen-induced electronic phase transition rate of the SmNiO3 film.

[0066] Example 19:

[0067] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the SmNiO3 film was contacted with a Cu phase and placed in a 0.05 mol / L oxalic acid solution. A negative potential of -1 V was applied to the SmNiO3 film, and after a period of time, the sample was removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 film was then measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. Comparing the results with those of Example 17, it can be found that the rate of increase in the resistance ratio further increases when a negative electric field is applied to the SmNiO3 film, indicating that applying a larger negative electric field can further accelerate the hydrogen-induced electronic phase transition rate of the SmNiO3 film.

[0068] Example 20:

[0069] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the SmNiO3 film was contacted with a Cu phase and placed in a 0.05 mol / L oxalic acid solution. A positive potential of 1 V was applied to the SmNiO3 film, and after a period of time, the sample was removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 film was then measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. Comparing the results with those of Example 18, it can be found that the rate of increase in the resistance ratio further slows down when a positive electric field is applied to the SmNiO3 film, indicating that applying a larger positive electric field can further suppress the hydrogen-induced electronic phase transition rate of the SmNiO3 film.

[0070] Example 21:

[0071] Using SmNiO3 thin films as the research object, the resistance or resistivity of the film before the hydrogen-induced phase transition was measured, referred to as the initial resistance or resistivity. Then, the SmNiO3 film was contacted with a metallic Zn phase and placed in a 0.05 mol / L ammonia solution for a period of time. The sample was then removed, rinsed with deionized water, and dried. The resistance or resistivity of the SmNiO3 film was measured again. The ratio of the obtained resistance to the initial resistance was plotted on the ordinate, and time was plotted on the abscissa. The above process could be repeated to obtain the change in the resistance ratio over time. The resistance ratio decreased with time. Compared with Example 11, the rate of decrease in the resistance ratio over time was slower, indicating that the ability of the SmNiO3 film to suppress the hydrogen-induced electronic phase transition was weakened under weakly alkaline conditions.

[0072] 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 controlling the dynamics of hydrogen-induced electronic phase transition in metastable rare-earth nickel-based oxides, characterized in that... By contacting a specific metal electrode with a rare-earth nickel-based oxide material in a controllable shape and placing it in an acidic chemical environment, the difference in work function between the metal and the rare-earth nickel-based oxide material drives the transfer of hydrogen ions in the chemical environment. This allows the electronic configuration of the rare-earth nickel-based oxide material to change at a controllable rate from a trivalent nickel-dominated itinerant electronic structure to a divalent nickel-dominated localized electronic structure, triggering a controllable increase in the material's resistivity. This controllability can be achieved by changing the rare-earth element, electrode type, electrode shape, and pH value. When a specific metal electrode is contacted with the rare-earth nickel-based oxide material in a controllable shape and placed in an alkaline chemical environment, a sharp decrease in the material's resistivity will be triggered. The crystal structure of the rare earth nickel-based perovskite oxide material is the ABO3 perovskite structure: the A site is a single rare earth element or a combination of multiple rare earth elements, and the B site is a single nickel element or a combination of nickel and other transition metals. The selected metal electrode needs to meet the following conditions: 1) The work function of the metal electrode and the rare earth nickel-based oxide material have a certain matching relationship. When the work functions of the metal electrode and the rare earth nickel-based oxide material are close, the difference is within 0.1 eV. The rate of the hydrogen-induced phase transition method provided by this invention is slow. As the difference in work functions between the metal electrode and the rare earth nickel-based oxide material increases, the rate of the hydrogen-induced phase transition method provided by this invention increases; 2) The metal electrode will not form a passivation film on its surface in acidic or alkaline chemical environments. Under the condition that the above two conditions are met, when the pH value is between 0 and 14, Cu, Ni, Zn, Al, Ag, Fe, Co, Pt, Pd, Mn, Ti, Cr, Ta, and W are selected.

2. The method for controlling the dynamics of hydrogen-induced electronic phase transition of metastable rare-earth nickel-based oxides as described in claim 1, characterized in that, The crystal structure of the rare earth nickel-based perovskite oxide material is the perovskite structure of ABO3: the A site is a single rare earth element or a combination of multiple rare earth elements, including dysprosium: Dy, erbium: Er, ytterbium: Yb, samarium: Sm, neodymium: Nd, europium: Eu, praseodymium: Pr, lanthanum: La, samarium neodymium: Sm x Nd 1-x , where 0 < x < 1, samarium praseodymium: Sm x Pr 1-x , where 0 < x < 1, europium neodymium: Eu x Nd 1-x , where 0 < x < 1, europium praseodymium: Eu x Pr 1-x , where 0 < x < 1; the B site is a single nickel element or a combination of nickel and other transition metals, including nickel: Ni, nickel strontium: Ni x Sr 1-x , where 0 < x < 1, nickel manganese: Ni x Mn 1-x , where 0 < x < 1, nickel zinc: Ni x Zn 1-x , where 0 < x < 1, nickel cobalt: Ni x Co 1-x , where 0 < x < 1, nickel iron: Ni x Fe 1-x , where 0 < x < 1, nickel copper: Ni x Cu 1-x , where 0 < x < 1, nickel vanadium: Ni x V 1-x , where 0 < x < 1; furthermore, the rare earth nickel-based perovskite oxide includes various different forms, rare earth nickel-based perovskite oxide powder, rare earth nickel-based perovskite oxide nanowire, rare earth nickel-based perovskite oxide thin film, rare earth nickel-based perovskite oxide ceramic.

3. The method for controlling the dynamics of hydrogen-induced electronic phase transition of metastable rare-earth nickel-based oxides as described in claim 1, characterized in that, The metal electrodes are categorized into discontinuous and continuous shapes. The size and spacing of the discontinuous array metal electrodes vary from micrometers to millimeters. The shapes of the discontinuous array metal electrodes include: array-like dots, strips, triangles, squares, pentagons, and hexagons. Continuous metal electrodes are millimeter-sized and larger. Continuous metal electrodes continuously cover a portion of the film surface without forming an array distribution structure, and include circular, rectangular, square, triangular, pentagonal, and hexagonal shapes. The contact methods between the rare-earth nickel-based perovskite oxide and the metal electrodes include two forms: first, the metal electrode is placed on the rare-earth nickel-based perovskite oxide, which is simple to operate and separable; second, the metal electrode is deposited on the rare-earth nickel-based perovskite oxide by magnetron sputtering or vapor deposition, making the metal electrode and the rare-earth nickel-based perovskite oxide difficult to separate.

4. The method for controlling the dynamics of hydrogen-induced electronic phase transition of metastable rare-earth nickel-based oxides as described in claim 1, characterized in that, The acidic or alkaline chemical environment referred to includes either a solution environment or an aerosol environment. Acidic or alkaline chemical solution environment: 1) Acid solutions: including hydrochloric acid, acetic acid, oxalic acid, and sulfuric acid; 2) Acidic salt solutions: including sodium bicarbonate, calcium bicarbonate, sodium bisulfate, and sodium hydrosulfide; 3) Alkaline solutions: including sodium hydroxide, potassium hydroxide, and ammonia; Acidic or alkaline aerosol environments: 1) Acidic aerosol environment: including hydrogen chloride, hydrogen sulfide, sulfur dioxide, sulfur trioxide, carbon dioxide, nitrogen dioxide, and chlorine; 2) Alkaline aerosol environment: including ammonia, hydrazine, and phosphine; the pH value of the above acidic or alkaline aerosol environments is between 0 and 14.

5. The method for controlling the dynamics of hydrogen-induced electronic phase transition of metastable rare-earth nickel-based oxides as described in claim 1, characterized in that, The dynamic regulation of the hydrogen-induced electronic phase transition of metastable rare-earth nickel-based oxides can be further controlled by electric fields in terms of rate and reversibility. Applying a negative electric field or a pulsed electric field to rare-earth nickel-based oxides can accelerate the hydrogen-induced phase transition rate. Applying a positive electric field or a pulsed electric field to rare-earth nickel-based perovskite oxides can slow down the hydrogen-induced phase transition rate. Adjusting the voltage can regulate the ability to accelerate or suppress the hydrogen-induced phase transition rate. The minimum applied voltage is in the millivolt range, and the maximum voltage does not exceed one hundred volts.

6. The application of the method for controlling the dynamics of hydrogen-induced electronic phase transition of metastable rare-earth nickel-based oxides as described in claim 1, characterized in that, Application areas include: 1) By utilizing the reasonable matching of the work function between the metal electrode and the rare earth nickel-based oxide (±0.1eV) and the selection of the acidity or alkalinity of the chemical environment, the degree and rate of hydrogen-induced electronic phase transition of rare earth nickel-based oxide can be precisely designed. The control range of the hydrogen-induced phase transition rate is from 0.001 times per minute to 1,000,000 times per minute, thereby assisting its application in the fields of brain-like computing and bionic neural networks; 2) Based on the changing characteristics of hydrogen-induced electronic phase transition of metal electrodes and rare earth nickel-based oxide in chemical environments with different pH values, chemical environments with different acid and alkali concentrations can be detected.

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