A carboxylic acid amine hybrid perovskite material, a preparation method and application thereof

Abstract

This application discloses a carboxylic acid amine hybrid perovskite material, its preparation method, and its applications, belonging to the field of functional materials. The chemical formula of the carboxylic acid amine hybrid perovskite material is C8H. 16 Ag2I3NO2. This carboxylic acid amine hybrid perovskite material exhibits excellent flexural conductivity, and its synthesis method is simple, low-cost, with mild reaction conditions and high stability, making it an excellent carboxylic acid amine hybrid perovskite material for flexural conductivity applications.

Description

Technical Field

[0001] This application relates to a carboxylic acid amine hybrid perovskite material, its preparation method, and its application, belonging to the field of functional materials. Background Technology

[0002] Flexoelectricity is typically described as polarization induced by non-uniform deformation, such as deformation caused by strain or electric field gradients. Strain gradients can locally disrupt the inversion symmetry of crystals, leading to induced polarization in the material. Therefore, flexoelectricity is a widespread electromechanical coupling phenomenon in solid dielectric materials. Both strain and electric field gradients increase rapidly with decreasing material size. While macroscopic flexoelectricity is often neglected, it significantly impacts the physical properties of materials at the micro and nanoscale. Unlike piezoelectricity and electrostriction, flexoelectricity exhibits unique size-dependent characteristics, unaffected by material symmetry or the Curie temperature of ferroelectric materials. Flexoelectricity is a widely observed phenomenon that has recently attracted considerable research attention due to its broad potential applications across various disciplines, including actuators, sensors, and manipulating the properties of ferroelectric thin films. Flexoelectricity describes the interaction between mechanical strain gradients and electric polarization, termed the direct flexoelectric effect. Conversely, it also includes the coupling between electric field gradients and mechanical stress, termed the inverse flexoelectric effect. These two complementary phenomena characterize the bidirectional relationship between strain and polarization, and between electric field and stress, within the framework of flexoelectricity. When non-uniform external forces are applied, non-conductive materials deform, leading to strain gradients within their structure and consequently polarization. Furthermore, opposing charges of positive and negative natures manifest on the facing surfaces. Over the past century, piezoelectric materials, represented by piezoelectric ceramics, have made significant progress and are widely used in transducers, sensors, actuators, and energy harvesters. The development of the flexoelectric effect has the potential to overcome the limitations of the piezoelectric effect. Unlike the piezoelectric effect, the flexoelectric effect is not limited by material symmetry and remains stable above the Curie temperature. This effect has enormous application potential in sensors, actuators, and next-generation electronic devices. Therefore, research on the flexoelectric effect is of profound significance.

[0003] Compared to the interlayer organic monoamine cations in traditional perovskite materials, aminocarboxylic acids containing -COOH can enrich the interaction modes of the interlayer organic cation bilayer, such as strong OH…O hydrogen bonding with a certain orientation. This is beneficial for dipole formation and effectively suppresses van der Waals interactions, thereby enhancing phase stability. Furthermore, the strong OH…O hydrogen bonding between the organic cation bilayers can overcome the growth habit of layered crystal stacking, which is beneficial for the preparation and growth of large-size, high-quality crystals, providing material support for the design and assembly of crystal devices applied to flexural effects. Therefore, carboxylic acid-amine hybrid perovskites are a class of functional materials with great development potential and are expected to become an ideal material system for developing devices with strong flexural effects. Summary of the Invention

[0004] This invention provides a carboxylic acid amine hybrid perovskite material for flexoelectric effect, its preparation method, and its application. The carboxylic acid amine hybrid perovskite material of this invention has excellent flexoelectric effect, and the synthesis method is simple, low-cost, mild in reaction conditions, and highly stable. It is an excellent carboxylic acid amine hybrid perovskite material for flexoelectric effect.

[0005] According to the first aspect of this application, a carboxylic acid amine hybrid perovskite material is provided.

[0006] A carboxylic acid amine hybrid perovskite material, wherein the chemical formula of the carboxylic acid amine hybrid perovskite material is C8H 16 Ag₂I₃NO₂ has the following molecular structure:

[0007]

[0008] Optionally, the carboxylic acid amine hybrid perovskite material belongs to the central triclinic crystal system at room temperature. Space group, cell parameters are Z = 2,

[0009] According to a second aspect of this application, a method for preparing a carboxylic acid amine hybrid perovskite material is provided.

[0010] The preparation method of the above-mentioned carboxylic acid amine hybrid perovskite material includes:

[0011] Trans-tranexamic acid and silver oxide are added to an aqueous solution of hydroiodic acid, heated to 80-100°C, and then stirred until completely dissolved to form a clear solution. The resulting solution is then kept at 70-80°C for 12-24 hours and then cooled to 30-40°C to obtain the carboxylic acid amine hybrid perovskite material.

[0012] Optionally, the molar ratio of trans-tranexamic acid to silver oxide is 1:1-1.5.

[0013] Optionally, the ratio of silver oxide to hydroiodic acid aqueous solution is 1 mmol: 2-4 ml.

[0014] Optionally, the weight percentage of HI in the hydroiodic acid aqueous solution is 55-58%.

[0015] Optionally, the cooling rate is 1-2℃ / day.

[0016] Optionally, the preparation method of the carboxylic acid amine hybrid perovskite material includes: at room temperature, adding trans aminomethyl tranexamic acid and silver oxide in a stoichiometric ratio of 1:1 into an aqueous solution of hydroiodic acid, heating to 80-100°C, and then stirring until completely dissolved to form a clear solution. Subsequently, the obtained solution is placed in a constant temperature chamber at 80°C for 24 hours, and then the temperature of the constant temperature chamber is slowly reduced to 30-40°C to obtain the carboxylic acid amine hybrid perovskite material for flexural effect.

[0017] According to a third aspect of this application, an application of a carboxylic acid amine hybrid perovskite material is provided.

[0018] The above-mentioned carboxylic acid amine hybrid perovskite materials are used in the field of flexural electricity.

[0019] The beneficial effects that this application can produce include:

[0020] The carboxylic acid amine hybrid perovskite material, its preparation method, and its application provided in this application have excellent flexural conductivity. Moreover, the synthesis method is simple, low-cost, mild, and highly stable, making it an excellent carboxylic acid amine hybrid perovskite material for flexural conductivity. Attached Figure Description

[0021] Figure 1 These are crystal photographs of the carboxylic acid amine hybrid perovskite material prepared in Example 1;

[0022] Figure 2 This is a molecular schematic diagram of the carboxylic acid amine hybrid perovskite material prepared in Example 1;

[0023] Figure 3 This is a crystal structure packing diagram of the carboxylic acid amine hybrid perovskite material prepared in Example 1;

[0024] Figure 4 These are X-ray powder diffraction comparison images of the carboxylic acid amine hybrid perovskite material prepared in Example 1;

[0025] Figure 5 This is the optical absorption spectrum of the carboxylic acid amine hybrid perovskite material prepared in Example 1;

[0026] Figure 6 The current-strain curves are those of the carboxylic acid amine hybrid perovskite material prepared in Example 1. Detailed Implementation

[0027] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0028] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0029] Unless otherwise specified, all test methods are standard and all instrument settings are those recommended by the manufacturer.

[0030] The analysis method in the embodiments of this application is as follows:

[0031] The crystallographic data analysis was performed using a Bruker D8 X-ray single-crystal diffractometer at 300K, with data collected using a Mo light source.

[0032] The instrument used for X-ray powder diffraction analysis was a Miniflex-600 diffractometer, and the conditions were 300K.

[0033] The instrument used for optical absorption spectroscopy analysis was a PerkinElmer UV-Vis-NIR spectrophotometer, model Lambda 950, at 300K.

[0034] The instruments used for current-strain curve analysis were a DMA850 dynamic mechanical analyzer and a Keithel electrometer (6517B / E), under conditions of 300K.

[0035] Example 1

[0036] Silver iodine tranexamic acid C8H 16 The method for synthesizing Ag2I3NO2 includes the following steps in sequence:

[0037] (1) Add trans-tranexamic acid and silver oxide to hydroiodic acid aqueous solution in a stoichiometric ratio of 1:1, stir and heat to 90°C, then continue stirring for 35 minutes until completely dissolved to form a clear solution;

[0038] (2) The obtained solution was then placed in a constant temperature chamber at 80°C for 24 hours;

[0039] (3) Finally, after cooling to 30℃ at a rate of 1℃ / day, the following is obtained: Figure 1 The black, blocky crystals shown are silver iodine tranexamic acid.

[0040] The weight percentage of HI in hydroiodic acid is 57%.

[0041] The dosage of both trans-tranexamic acid and silver oxide was 1 mmol.

[0042] The volume of hydroiodic acid aqueous solution used is 3 ml.

[0043] A suitable amount of single crystal was selected and ground into uniform, fine particles. Then, the X-ray powder diffraction pattern of the compound was obtained using a Miniflex-600 diffractometer, as shown below. Figure 4 As shown, the experimentally measured X-ray powder diffraction peaks are in good agreement with the theoretical simulation results, indicating that the phase purity is very high and there are no other obvious impurities.

[0044] The unit cell parameters of this embodiment are as follows: Z = 2, Belongs to the triclinic crystal system, 1 _ Point group, P1 _ Space group.

[0045] Example 2

[0046] Structural characterization of carboxylic acid amine hybrid perovskite materials for flexural electrical effect, such as Figure 2 and 3 As shown, it is a central triclinic crystal system at room temperature. Space group, cell parameters are Z = 2, Single-crystal structure analysis shows that the trans-tranexamic acid cation (t-ACH) + The constructed two-dimensional hybrid perovskites include t-ACH + The perovskite consists of an organic layer and an inorganic framework composed of Ag₂I₃. The most significant structural feature is the interconnection of adjacent spacer cation layers via strong OH…O hydrogen bonds, which effectively suppress van der Waals gaps. Typically, a typical two-dimensional RP-type perovskite contains two organic cation spacer layers, with a monoammonium cation (R-NH₃) forming the spacer. + The organic spacer is connected to the perovskite layer via hydrogen bonds at one end, thus creating van der Waals gaps between adjacent organic spacer layers. In contrast, strong OH…O hydrogen bonds connect adjacent t-ACH layers. + The cationic layer effectively reduces the band gap between adjacent organic layers, thus enhancing phase stability.

[0047] Example 3

[0048] Absorption spectroscopy testing of carboxylic acid amine hybrid perovskite materials for flexoelectric effect, such as Figure 5 As shown, the absorption cutoff edge of the carboxylic acid amine hybrid perovskite material used for the flexoelectric effect is approximately 770 nm. Based on T auc Equation ([hvF(R)) ∞ )] n =A(hv-E) g The calculated band gap value is approximately E. g =1.6eV.

[0049] Example 4

[0050] Flexural effect testing of carboxylic acid amine hybrid perovskite materials for flexural effect, such as Figure 6 As shown, we constructed a two-probe device using a large-size single crystal to study its flexural properties. At a frequency of 1 Hz, under different strains, the current gradually increased with increasing strain. The calculated flexural coefficient was 743 nC / m, demonstrating its potential application value in the field of flexural electricity.

[0051] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A carboxylic acid amine hybrid perovskite material, characterized in that, The chemical formula of the carboxylic acid amine hybrid perovskite material is C8H. 16 Ag₂I₃NO₂ has the following molecular structure:

2. The carboxylic acid amine hybrid perovskite material according to claim 1, characterized in that, The carboxylic acid amine hybrid perovskite material belongs to the central triclinic crystal system at room temperature, P1 _ Space group, cell parameters are Z = 2, 3. The method for preparing the carboxylic acid amine hybrid perovskite material according to claim 1 or 2, characterized in that, include: Trans-tranexamic acid and silver oxide are added to an aqueous solution of hydroiodic acid, heated to 80-100°C, and then stirred until completely dissolved to form a clear solution. The resulting solution is then kept at 70-80°C for 12-24 hours and then cooled to 30-40°C to obtain the carboxylic acid amine hybrid perovskite material.

4. The preparation method according to claim 3, characterized in that, The molar ratio of trans-tranexamic acid to silver oxide is 1:1-1.

5.

5. The preparation method according to claim 3, characterized in that, The ratio of silver oxide to hydroiodic acid aqueous solution is 1 mmol: 2-4 ml.

6. The preparation method according to claim 3, characterized in that, The weight percentage of HI in hydroiodic acid aqueous solution is 55-58%.

7. The preparation method according to claim 3, characterized in that, The cooling rate is 1-2℃ / day.

8. The application of the carboxylic acid amine hybrid perovskite material according to claim 1 or 2 in the field of flexural electricity.

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