Directionally aligned hybrid electronic-ionic thermoelectric hydrogels and methods of making the same

Abstract

The application relates to the technical field of thermoelectric materials, and discloses a directionally arranged mixed electronic-ion thermoelectric hydrogel and a preparation method thereof, which comprises a three-dimensional skeleton composed of at least poly(3,4-ethylenedioxythiophene): polystyrene sulfonate, and redox ion pairs and electrolyte salts loaded in the skeleton. The skeleton has a through-hole structure extending in a single direction, which can realize high-speed directional transmission of electrons; meanwhile, the redox ion pairs and the electrolyte salts form a continuous ion transmission path in the skeleton, endowing the material with efficient directional ion conduction capacity. The application realizes high electrical conductivity and high Seebeck coefficient by constructing a directional double-channel structure, and couples thermoelectric current effect and ion heat diffusion effect, so that excellent thermoelectric output performance is finally obtained.

Description

Technical Field

[0001] This invention relates to the field of thermoelectric materials technology, and more specifically, to a directionally aligned hybrid electron-ion thermoelectric hydrogel and its preparation method. Background Technology

[0002] Thermoelectric materials can directly convert heat energy into electrical energy, and have significant application value in sustainable energy harvesting and wearable electronic devices. Traditional thermoelectric materials mainly rely on electrons as charge carriers (e-TE materials), such as optimized polymers or inorganic semiconductors. These materials typically have high electrical conductivity (σ), but their Seebeck coefficient (S, i.e., thermoelectric potential) is limited by electron entropy and is generally only 10⁻¹⁰. 2 µV·K -1 The sheer magnitude of these voltages creates a bottleneck in improving thermoelectric conversion efficiency. In recent years, ion thermoelectric materials have gained attention due to their ability to generate enormous ion thermal voltages (up to mV·K). -1 These materials have attracted widespread attention due to their high electrical conductivity (on the order of magnitude of 10⁻⁶ S·m⁻¹), demonstrating their potential to break through the limits of traditional thermoelectric materials. However, they generally suffer from low electrical conductivity (typically below 10⁻⁶ S·m⁻¹). -1 This severely limits its power factor (PF = S). 2 σ) and the final energy output density.

[0003] Given the complementary Seebeck coefficient and conductivity of electronic and ionic thermoelectric materials, researchers have begun exploring hybrid electronic-ionic conductor strategies that combine the two. This strategy aims to leverage a continuous electronic conduction network to ensure high conductivity while introducing migratable ions to generate high ionic thermal voltage, thereby synergistically improving overall thermoelectric performance. However, most current hybrid electronic-ionic thermoelectric materials still face two key structural bottlenecks in their pursuit of high-performance applications: Firstly, the disordered microstructure leads to a bottleneck in transport efficiency. Currently, thermoelectric gels prepared by methods such as chemical crosslinking and solvent-induced phase separation typically form random, isotropic three-dimensional crosslinked networks. In this disordered structure, electron transport paths are tortuous, ion migration is heavily hindered, and interface scattering is severe, making it difficult to further improve electronic conductivity. Furthermore, the thermal diffusion effect of ions is weakened due to the circuitous paths, failing to fully leverage the synergistic potential of both electron and ion transport mechanisms.

[0004] Secondly, there is insufficient coupling between the functional structure and the transmission channel. Current research focuses on the regulation of the chemical composition of materials or simply the physical mixing of conductive polymers with ionic components. Summary of the Invention

[0005] This invention provides a directionally aligned hybrid electron-ion thermoelectric hydrogel and its preparation method. The method prepares a poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS)-based hydrogel with directionally aligned channels. The oriented PEDOT enrichment walls provide efficient electron transport paths, while the parallel-aligned through-channels provide ideal highways for ion migration and thermal diffusion, thereby achieving a synergistic improvement in Seebeck coefficient and conductivity. This addresses the problem in existing technologies where thermoelectric gels prepared through chemical crosslinking or solvent induction have random network structures, resulting in tortuous electron conduction paths and high ion diffusion resistance. This limits further improvement in the intrinsic conductivity of the material and hinders the full manifestation of the ion thermal diffusion effect, making it difficult to simultaneously achieve high Seebeck coefficient and high conductivity.

[0006] The details are as follows: First, the present invention provides a directionally aligned hybrid electron-ion thermoelectric hydrogel, comprising a framework composed of at least poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), and redox ion pairs and electrolyte salts loaded in the framework; the framework has a through-pore structure extending in a single direction, which enables high-speed directional electron transport; at the same time, the redox ion pairs and electrolyte salts form a continuous ion transport path in the framework, giving the material efficient directional ion conduction capability.

[0007] As described above, based on the through-hole structure extending in a single direction, a dual transport channel arranged in parallel in space is formed inside the hydrogel: (1) an electron transport channel, specifically formed by interconnecting PEDOT conductive domains that are oriented and enriched along the direction of the channel, providing a fast directional conduction path for electrons; (2) an ion transport and thermal diffusion channel, specifically formed by the hydration space inside the through-hole, in which redox ion pairs and electrolyte salts are loaded, providing a low-resistance directional diffusion path for ions.

[0008] In the aforementioned process, the growth of ice crystals is used as a dynamic template to replicate and fix its oriented structure through physical processes, rather than through strong chemical modification, such as the use of concentrated sulfuric acid in existing technologies, where the strong acid treatment process destroys the hydrophilicity and ion loading capacity of the gel.

[0009] In the foregoing, redox ion pairs are ion pairs capable of undergoing reversible redox reactions and generating thermoelectric potential under a temperature gradient. Specifically, redox ion pairs include at least one of ferricyanide / ferrocyanide pairs, halogen / polyhalide pairs, and metal ion variable valence pairs; more specifically, they include potassium ferricyanide / potassium ferrocyanide ([Fe(CN)6)6) 4- / [Fe(CN)6] 3- ), potassium iodide / iodine (I - / I3- ), stannous chloride / stannous chloride (Sn) 2+ / Sn 4+ At least one of the following, with a concentration of 0.05 M to 0.3 M.

[0010] As mentioned above, the electrolyte salt includes at least one of sodium chloride (NaCl), potassium chloride (KCl), copper chloride (CuCl2), sodium hydroxide (NaOH), and lithium hydroxide (LiOH), with a concentration of 0.1 M to 1.0 M.

[0011] Second, the present invention provides a method for preparing the aforementioned oriented hybrid electron-ion thermoelectric hydrogel, comprising the following steps: S1 uses poly(3,4-ethylenedioxythiophene):polystyrene sulfonate dispersion as a precursor solution; S2 The mold containing the precursor liquid is placed in a cold source for freezing, and then transferred to an organic solvent system for thawing to obtain a directional gel; the cold source includes a unidirectional temperature gradient field; S3 oriented gel is immersed in an impregnation solution, which includes redox ion pairs, electrolyte salts and water; after the impregnation is completed, it is heat-treated to obtain a hydrogel.

[0012] The aforementioned unidirectional temperature gradient field includes: The sample container is filled with a cryogenic cooling medium. A metal rod is inserted into the sample container, and the metal rod is in seamless contact with the sample container to ensure the sealing of the sample container; the metal rod is in contact with the inner bottom of the sample container; the bearing surface of the metal rod supports a mold containing a precursor liquid.

[0013] Preferably, the cryogenic cooling medium is liquid nitrogen; the metal rod is a copper or aluminum rod; the temperature of the sample-bearing surface is controlled between -20℃ and -80℃ by adjusting the depth of the metal rod immersed in the cooling medium. The sample container is a simple, homemade laboratory container (e.g., dimensions: 20 cm * 30 cm * 20 cm), and those skilled in the art can also choose similar containers for operation. Specifically, a foam-insulated box with a lid can be selected, with multiple metal rods inserted into the foam-insulated box after passing through the lid.

[0014] In the aforementioned, the phase separation inducing agent accounts for 0.1 to 20 wt% of the mass of poly(3,4-ethylenedioxythiophene):polystyrene sulfonate.

[0015] As described above, the precursor solution also includes a phase separation inducing agent, which includes at least one of a polyacid, an organic polar solvent, and a surfactant. Specifically, the polyacid includes at least one of phosphotungstic acid, silicotungstic acid, and phosphomolybdic acid; the organic polar solvent includes at least one of ethanol, ethylene glycol, and dimethyl sulfoxide; the surfactant includes a cationic surfactant; and the cationic surfactant includes at least one of hexadecyltrimethylammonium bromide and dodecyltrimethylammonium bromide.

[0016] In the aforementioned S1, the mixing time is 0.5~24 h and the mixing speed is 200~500 r / min.

[0017] In the aforementioned S2, the freezing temperature is -80 ℃ to -20 ℃, and the freezing time is 2 to 12 hours.

[0018] In the aforementioned S2, the thawing time is 5~25 ℃ and the thawing time is 12~48 h.

[0019] In the aforementioned S2, the organic solvent includes at least one of isopropanol, ethylene glycol, ethanol, and dimethyl sulfoxide.

[0020] In the aforementioned S3, the immersion temperature is 25~90 ℃ and the immersion time is 2~48 h.

[0021] In the aforementioned process, in step S3, the heat treatment temperature is 50~90 ℃ and the treatment time is 10~120 min.

[0022] In the aforementioned process, the precursor solution was placed in a unidirectional temperature gradient field. Under these conditions, ice crystals grew directionally along the temperature gradient direction (e.g., vertically), displacing and concentrating PEDOT:PSS particles within narrow regions between the ice crystals. Subsequently, the completely frozen sample was transferred to a low-temperature organic solvent for slow thawing. Optimized heat and mass transfer during this process facilitated in-situ phase separation of PEDOT and PSS, solidifying to form a long-range ordered, structurally complete three-dimensional conductive hydrogel framework, resulting in a directionally aligned conductive hydrogel. Immersing the hydrogel in an impregnation solution, due to the interconnected and hydrophilic pores of the framework, the solution rapidly wetted the hydrogel through capillary action, allowing ions to diffuse uniformly and become loaded throughout the entire three-dimensional oriented pore network. Here, transportable ions are not randomly dispersed but enriched in the oriented pore spaces, thus forming a highly efficient ion transport network. The resulting hydrogel was gently rinsed with deionized water to remove residual salts. Subsequently, heat treatment can be performed to promote further cross-linking and stabilization of the PEDOT:PSS backbone, ultimately obtaining the oriented mixed electronic / ionic thermoelectric hydrogel.

[0023] Third, the present invention provides a hybrid electron-ion thermoelectric hydrogel obtained by the aforementioned preparation method.

[0024] The technical mechanism employed in this invention is as follows: (1) The PEDOT:PSS framework provided by this invention is a framework with a highly ordered, interconnected pore structure, which not only provides a continuous electron transport path, but also achieves extremely high electronic conductivity; experiments show that the conductivity of the hydrogel provided by this invention can reach 123.7 S·m. -1 This invention significantly outperforms random-structure gels with similar chemical compositions. The hydrogel provided by this invention possesses regular channels that also serve as ideal ion transport highways. When loaded with redox ion pairs and electrolyte salts, the diffusion resistance of ions within these oriented channels is extremely low, greatly enhancing the thermal diffusion effect and contributing a significant ion thermal voltage. This allows the Seebeck coefficient of the material to break through the limitations of traditional electronic thermoelectric materials, reaching 1.92 mV·K. -1 The magnitude.

[0025] (2) The hydrogel provided by this invention has a highly ordered oriented structure, which enables the electron conduction path and ion diffusion path to be arranged in parallel and independent in space at the microscale, avoiding mutual blockage. Under the temperature gradient, the electron thermal flux and ion thermal diffusion flux are efficiently generated and transported in their respective optimized channels, and the resulting thermoelectric potentials can be superimposed. This synergistic effect physically decouples the traditional inverse relationship between the Seebeck coefficient and conductivity. Attached Figure Description

[0026] Figure 1 This is a schematic diagram illustrating the preparation of the directionally aligned electron-ion hybrid thermoelectric hydrogel of the present invention; Figure 2 Comparison of the microstructures of oriented and random PEDOT:PSS hydrogels: (a) top view and (b) side view of the oriented hydrogel; (c, c') top view and (d) side view of Example 1; (e, e') top view and (f) side view of Example 2; (g, g') top view and (h) side view of Comparative Example 1. Figure 3 Seebeck coefficient results of the oriented electron-ion hybrid thermoelectric hydrogel of the present invention under different ion transport conditions (Example 1, Comparative Examples 2 and 3): A-P0@Fe, oriented PEDOT:PSS@K3[Fe(CN)6] / K4[Fe(CN)6] thermoelectric hydrogel; A-P0@Na, oriented PEDOT:PSS@NaCl thermoelectric hydrogel; A-P0@Fe / Na, oriented PEDOT:PSS@K3[Fe(CN)6] / K4[Fe(CN)6] / NaCl thermoelectric hydrogel; Figure 4The following are the electrical performance results of the oriented electron-ion hybrid thermoelectric hydrogel of the present invention under different ion transport conditions (Example 1, Comparative Examples 2 and 3): A-P0@Fe, oriented PEDOT:PSS@K3[Fe(CN)6] / K4[Fe(CN)6] thermoelectric hydrogel; A-P0@Na, oriented PEDOT:PSS@NaCl thermoelectric hydrogel; A-P0@Fe / Na, oriented PEDOT:PSS@K3[Fe(CN)6] / K4[Fe(CN)6] / NaCl thermoelectric hydrogel; Figure 5 The following are the PF values ​​of the oriented electron-ion hybrid thermoelectric hydrogel of the present invention under different ion transport conditions (Example 1, Comparative Examples 2 and 3): A-P0@Fe, oriented PEDOT:PSS@K3[Fe(CN)6] / K4[Fe(CN)6] thermoelectric hydrogel; A-P0@Na, oriented PEDOT:PSS@NaCl thermoelectric hydrogel; A-P0@Fe / Na, oriented PEDOT:PSS@K3[Fe(CN)6] / K4[Fe(CN)6] / NaCl thermoelectric hydrogel; Figure 6 Open-circuit voltage-temperature difference curves, Seebeck coefficients, Nyquist plot fitting curves, and conductivity results for oriented and random structured electron-ion mixed thermoelectric hydrogels (Example 2 and Comparative Example 1): PD1@Fe / Na, PEDOT:PSS@K3[Fe(CN)6] / K4[Fe(CN)6] / NaCl thermoelectric hydrogel after treatment with 1wt% DMSO phase separator; Figure 7 Output current-voltage curves and corresponding output power densities under different temperature differences (Example 1); Figure 8 This is a schematic diagram of a directional refrigeration device. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0028] Example 1 This embodiment provides a directionally aligned hybrid electron-ion thermoelectric hydrogel and its preparation method, the preparation process of which is as follows: Figure 1 As shown, it includes the following steps: S1. Preparation of the directional PEDOT:PSS electronic framework: 1.0 g of PEDOT:PSS aqueous dispersion was injected into a polytetrafluoroethylene mold (10×10×10 mm). 3 The mold was placed in a cryostat approximately 10 cm above liquid nitrogen. By controlling the distance between the bottom of the sample and the liquid nitrogen, a unidirectional temperature gradient was established in the vertical direction, and the sample was frozen at -80 °C for 2 h. Ice crystals grew directionally along the temperature gradient (vertical direction), and PEDOT:PSS was displaced and enriched in the inter-crystal region, forming a pre-arranged structure. Subsequently, the completely frozen sample was transferred to ethylene glycol at 4 °C and slowly thawed for 24 h to obtain a PEDOT:PSS hydrogel framework with a vertically oriented pore structure.

[0029] S2. Construction of ion transport channels: Prepare an impregnation solution containing 0.3 M, specifically a mixed aqueous solution of K3[Fe(CN)6] / K4[Fe(CN)6] (molar ratio 1:1) and 1.0 M NaCl. Completely immerse the oriented hydrogel obtained in step S1 in the impregnation solution and immerse it in a constant temperature water bath at 60 ℃ for 24 h to ensure that redox ion pairs and ion salts are fully diffused and uniformly loaded within the oriented channels of the hydrogel.

[0030] S3. Post-treatment: Remove the impregnated hydrogel and briefly rinse the surface with deionized water to remove adsorbed salts. Then, place it in a 90 °C oven for 2 h to promote further ordering and cross-linking of the PEDOT chains, enhancing structural stability. Finally, a directionally aligned hybrid electron-ion thermoelectric hydrogel is obtained.

[0031] Example 2 The preparation method is basically the same as that in Example 1, except that in step S1, the PEDOT:PSS dispersion is mixed with 1 wt% of the phase separating agent dimethyl sulfoxide (DMSO) and then injected into a polytetrafluoroethylene mold (10×10×10 mm). 3 ) is subjected to one-way freezing.

[0032] Example 3 The preparation method is basically the same as that in Example 1, except that in step S1, the exposed section of the metal rod (the distance from the liquid nitrogen surface to the mold) is lengthened to 15 cm to increase the thermal resistance, the temperature of the top mold rises significantly, a unidirectional temperature gradient is established in the vertical direction, and the mold is frozen at -50 ℃ for 6 h.

[0033] Example 4 The preparation method is basically the same as that in Example 1, except that in step S1, the completely frozen sample is transferred to isopropanol at 4 °C and thawed slowly for 48 h.

[0034] Example 5 The preparation method is basically the same as that in Example 1, except that in step S1, the completely frozen sample is transferred to distilled water at 4 °C and thawed slowly for 24 h.

[0035] Example 6 The preparation method is basically the same as that in Example 1, except that in step S2, the concentration of the K3[Fe(CN)6] / K4[Fe(CN)6] redox ion pair is 0.05 M.

[0036] Example 7 The preparation method is basically the same as that in Example 1, except that in step S2, the concentration of the K3[Fe(CN)6] / K4[Fe(CN)6] redox ion pair is 0.1 M.

[0037] Example 8 The preparation method is basically the same as that in Example 1, except that in step S2, the concentration of the K3[Fe(CN)6] / K4[Fe(CN)6] redox ion pair is 0.2 M.

[0038] Example 9 The preparation method is basically the same as that in Example 1, except that in step S2, the impregnation temperature is 40 °C, and other conditions remain unchanged.

[0039] Comparative Example 1 The preparation method is basically the same as that in Example 2, except that in step S1, the PEDOT:PSS dispersion is mixed with 1 wt% of the phase separating agent dimethyl sulfoxide (DMSO) and then injected into a polytetrafluoroethylene mold (10×10×10 mm). 3 The sample was directly immersed in liquid nitrogen for freezing, frozen at -80 °C for 10 h, and then thawed in ethylene glycol at 4 °C for 24 h.

[0040] Comparative Example 2 The preparation method is basically the same as that in Example 1, except that in step S2, the impregnation solution does not contain the K3[Fe(CN)6] / K4[Fe(CN)6] redox ion pair, but only 1.0 M NaCl.

[0041] Comparative Example 3 The preparation method is basically the same as that in Example 1, except that in step S2, the impregnation solution does not contain NaCl, but only contains 0.3 M of K3[Fe(CN)6] / K4[Fe(CN)6].

[0042] Test case The testing and characterization methods for the relevant performance are as follows: (1) Microstructure characterization: The microstructure of the hydrogel was observed using field emission scanning electron microscopy (FESEM). The sample was freeze-dried and then sputter-coated with gold.

[0043] (2) Conductivity testing (refer to the method in CN117288802A): All hydrogels were subjected to AC impedance spectroscopy using an electrochemical workstation to obtain electrochemical impedance spectra. Specific parameters were: AC voltage 10 mV, frequency range 0.1 Hz to 105 Hz. The Nyquist plot was fitted to the equivalent circuit using ZSimpWin software to obtain the electronic resistance (Re) and ionic resistance (R0) of the hydrogels. i ), and calculate the electronic conductivity (σ) e ) and ionic conductivity (σ i ).

[0044] (3) Seebeck coefficient test (refer to the method in CN117288802A): The Seebeck coefficient of the hydrogel was measured using a self-made device. Two commercial Pallas patches were used as the heat source and cold source, respectively, to generate a stable temperature gradient. Two commercial thermocouples were connected to the hot and cold ends of the thermogel, respectively, for real-time monitoring of temperature changes. Commercial graphene paper was used as the electrode. The change in open-circuit voltage was recorded in real time by a Keithley 2450 meter and a computer. The temperature difference of the sample was simultaneously detected by a multi-channel temperature recorder (EX4000) and the two thermocouples.

[0045] (4) Thermoelectric output performance test (refer to the method in CN117288802A): The hydrogel sample was integrated into a self-made vertical thermoelectric power generation module. Under a set temperature difference, its open-circuit voltage (V) was measured. oc ) and short-circuit current density (J sc By connecting external load resistors of different values, the output voltage and current are measured, and the output power density is calculated.

[0046] Test Results The hydrogels obtained in the above embodiments and comparative examples were subjected to performance tests, and the key results and analyses are as follows: 1. The key role of directional arrangement structure The hydrogel prepared in Example 2 has a long-range ordered directional pore structure. Figure 2 Its electrical conductivity can reach 123.7 S·m. -1 The Seebeck coefficient is as high as 1.92 mV·K. -1 In contrast, the hydrogel of Comparative Example 1 (randomly frozen) has a random porous structure, and its electrical conductivity and Seebeck coefficient are significantly lower than those of Example 2 (…). Figure 6 This demonstrates that the oriented arrangement structure provides a fast, low-resistance transport channel for electrons and ions, which is fundamental to achieving high performance.

[0047] 2. Negative impacts of missing transport ion components Figure 3-5 The results show that, although Comparative Example 2 (without redox ion pairs) has a conductivity of 125.5 S·m, -1 It is comparable to Example 1, but its Seebeck coefficient is extremely low (approximately 0.042 mV K). -1 This results in a negligible power factor. This strongly demonstrates that the introduction of redox ion pairs such as K3[Fe(CN)6] / K4[Fe(CN)6] is key to generating a large ion thermal diffusion potential, thereby obtaining a high Seebeck coefficient. The results of Examples 1, 5, 6, and 7 show that the Seebeck coefficient increases with increasing redox ion pair concentration.

[0048] The Seebeck coefficient of Comparative Example 3 (without NaCl) was 1.88 mV·K. -1 The conductivity is relatively high, but the total conductivity is extremely low (approximately 1.2 S·m). -1 This results in low output power. This indicates that high concentrations of ionic salts (such as NaCl) are crucial for providing sufficient ion carriers, achieving high ionic conductivity and overall conductivity, and are necessary conditions for realizing high power output.

[0049] 3. Overall thermoelectric performance Example 1 yielded a high efficiency of 455.97 µW·m -1 ·K -2 The power factor was [not specified]. Based on this, the assembled power generation module achieved an open-circuit voltage of 26.7 mV and a power output of 90.84 A·m at a temperature difference of 11 K. -2 The short-circuit current density is [value missing], and the maximum output power density reaches 623.82 mW·m. -2 It is significantly superior to the comparative example and most thermogel materials in the existing technology.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A directionally aligned hybrid electro -ionic thermoelectric hydrogel, characterized in that, It includes a three-dimensional framework consisting of at least poly(3,4-ethylenedioxythiophene):polystyrene sulfonate, and redox ion pairs and electrolyte salts loaded in the framework; the framework has a through-channel structure extending in a single direction.

2. The directionally aligned hybrid electron-ion thermoelectric hydrogel according to claim 1, characterized in that, Redox ion pairs include at least one of ferricyanide / ferrocyanide pairs, halogen / polyhalogen pairs, and metal ion valence-changing pairs.

3. The directionally aligned hybrid electron-ion thermoelectric hydrogel according to claim 2, characterized in that, The redox ion pair includes at least one of potassium ferrocyanide / potassium ferrocyanide, potassium iodide / iodine, and stannous chloride / stannous chloride.

4. The oriented hybrid electron-ion thermoelectric hydrogel according to claim 1, characterized in that, Electrolyte salts include at least one of sodium chloride, potassium chloride, copper chloride, sodium hydroxide, and lithium hydroxide.

5. A method for preparing a directionally aligned hybrid electron-ion thermoelectric hydrogel as described in any one of claims 1 to 4, characterized in that, Includes the following steps: S1 uses poly(3,4-ethylenedioxythiophene):polystyrene sulfonate dispersion as a precursor solution; S2 The mold containing the precursor liquid is placed in a cold source for freezing, and then transferred to an organic solvent system for thawing to obtain a directional gel; the cold source includes a unidirectional temperature gradient field; S3 oriented gel is immersed in an impregnation solution, which includes redox ion pairs, electrolyte salts and water; after the impregnation is completed, it is heat-treated to obtain a hydrogel.

6. The method for preparing the oriented hybrid electron-ion thermoelectric hydrogel according to claim 5, characterized in that, The precursor solution also includes a phase separation inducing agent; the phase separation inducing agent includes at least one of polyacids, organic polar solvents, and surfactants.

7. The method for preparing the oriented hybrid electron-ion thermoelectric hydrogel according to claim 6, characterized in that, The polyacids include at least one of phosphotungstic acid, silicotungstic acid, and phosphomolybdic acid; and / or, the organic polar solvents include at least one of ethanol, ethylene glycol, and dimethyl sulfoxide; and / or, the surfactants include cationic surfactants; the cationic surfactants include at least one of hexadecyltrimethylammonium bromide and dodecyltrimethylammonium bromide.

8. The method for preparing the oriented hybrid electron-ion thermoelectric hydrogel according to claim 5, characterized in that, Organic solvents include at least one of isopropanol, ethylene glycol, ethanol, and dimethyl sulfoxide.

9. The method for preparing the oriented hybrid electron-ion thermoelectric hydrogel according to any one of claims 5 to 8, characterized in that, In S1, the blending process involves stirring for 0.5-24 hours at a speed of 200-500 r / min; and / or, In S2, the freezing temperature is -80 ℃ to -20 ℃, and the freezing time is 2 to 12 h; and / or, In S2, the thawing time is 5~25 ℃, and the thawing time is 12~48 h; and / or, In S3, the impregnation temperature is 25~90 ℃, and the impregnation time is 2~48 h; and / or, In S3, the heat treatment temperature is 50~90 ℃ and the treatment time is 10~120 min.

10. A directionally aligned hybrid electron-ion thermoelectric hydrogel obtained by the preparation method according to any one of claims 5 to 9.

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