Preparation method of gel evaporator with vertically oriented channels and radial gradient structure
By preparing SA/HPC-PEDOT:PSS composite aerogels with vertically oriented channels and radial gradient structures, the contradiction between water supply and heat management in high-salt environments with single-oriented channel structures was resolved, achieving efficient evaporation and improved stability, making it suitable for stable evaporation of water under high salinity.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHIHEZI UNIVERSITY
- Filing Date
- 2026-03-23
- Publication Date
- 2026-06-02
AI Technical Summary
In the existing technology, the single-orientation channel structure is difficult to balance the "water-heat" contradiction of efficient water supply and heat management, as well as the problem of weak interfacial bonding of polyelectrolyte composite evaporators in high-salt environments, which leads to device instability.
A SA/HPC-PEDOT:PSS composite aerogel with an internal vertical/external radial structure was prepared using radial gradient freezing technology. The conjugated structure of PEDOT:PSS was used to achieve photothermal conversion, and chloride ions were actively repelled through the Donnan effect. The cross-linking of sodium alginate and calcium ions prevented salt crystallization.
It achieves high-efficiency evaporation, rapid water transfer, heat localization, and active salt resistance, improving the stability and efficiency of the evaporator and making it suitable for stable evaporation of water under high salinity.
Smart Images
Figure CN122126915A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of gel evaporator fabrication technology, and more particularly to a method for fabricating a gel evaporator with vertically oriented channels and a radial gradient structure. Background Technology
[0002] Freshwater scarcity has become a global problem, and solar-driven interfacial evaporation technology has received widespread attention in the field of high-salinity wastewater treatment due to its advantages of being green and having low energy consumption.
[0003] However, this technology still faces two major challenges in practical applications:
[0004] (1) Water-heat transfer contradiction:
[0005] While vertically oriented aerogels facilitate rapid water transport, heat tends to diffuse longitudinally into the bulk water phase, leading to heat loss. Radially oriented aerogels can effectively suppress heat conduction and achieve localized heat management, but their water transport performance is relatively inferior. A single-oriented pore structure cannot simultaneously achieve efficient water supply and heat retention.
[0006] (2) Salt crystallization and stability issues:
[0007] In high-salt environments, salts tend to crystallize at the evaporation interface, clogging the pores. Existing polyelectrolyte composite evaporators often employ a physical blending strategy of photothermal materials and polyelectrolytes, resulting in weak interfacial bonding and uneven dispersion of functional units, which affects the long-term stability of the device.
[0008] Therefore, in order to solve the "water-heat" contradiction that the existing single-oriented channel technology cannot achieve both efficient water supply and heat management, as well as the problem of weak interfacial bonding caused by physical blending, a new material is needed that combines efficient photothermal conversion, rapid water transport and anti-salt crystallization functions, and can achieve water-heat balance. This is of great significance for promoting the practical application of solar high-salt desalination technology and is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention
[0009] In view of this, the present invention provides a method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure. Using radial gradient freezing technology, a one-step method is employed to prepare an SA / HPC-PEDOT:PSS composite aerogel with an internal vertical / external gradient radial structure. The internal vertical channels ensure rapid water transport, while the external radial structure inhibits heat conduction, achieving thermal localization. Simultaneously, PEDOT:PSS is introduced as a multifunctional component; its conjugated structure endows it with efficient photothermal conversion capabilities, and the negative charge of the sulfonate group makes the network negatively charged, actively repelling chloride ions through the Donnan effect, thus integrating photothermal and active salt resistance functions. The aerogel prepared by this invention possesses efficient evaporation, rapid water transport, thermal localization, and active salt resistance properties, providing a new solution for resolving the contradiction between water and heat transport and achieving stable evaporation under high salinity.
[0010] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:
[0011] A method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure includes the following steps:
[0012] Step 1: Preparation of sodium alginate (SA) solution and hydroxypropyl cellulose (HPC) solution
[0013] Weigh out sodium alginate (SA), add it to deionized water, place it in a water bath, and stir until SA is completely dissolved to obtain a clear and homogeneous SA solution.
[0014] Weigh out hydroxypropyl cellulose (HPC), add deionized water, and stir at room temperature until the HPC is completely dissolved to obtain a transparent and viscous HPC solution.
[0015] Step 2: Preparation of the composite precursor solution
[0016] Measure the SA solution and HPC solution obtained in step 1, stir and mix them evenly, then add poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate PEDOT:PSS aqueous dispersion, stir at room temperature to obtain a uniformly dispersed composite precursor solution.
[0017] Step 3: Radial freeze forming and freeze drying
[0018] The precursor solution obtained in step 2 is injected into a radial freezing mold, and after being subjected to liquid nitrogen directional freezing treatment, it is taken out and then freeze-dried to obtain an SA / HPC-PEDOT:PSS porous framework with an internal vertical orientation / external radial gradient structure.
[0019] Step 4: Ion crosslinking and curing
[0020] The porous framework obtained in step 3 is immersed in a mixed solution of anhydrous calcium chloride, water and ethanol for cross-linking, and then immersed in deionized water to remove unreacted raw materials, thus obtaining an SA / HPC-PEDOT:PSS gel evaporator with vertically oriented channels and radial gradient structure.
[0021] The quantity of material taken is referred to as "parts" by weight.
[0022] Preferably, in the first step, the sodium alginate SA is 1-5 parts by weight, and the molecular weight of sodium alginate SA is 2.0 × 10⁻⁶. 5 g·mol -1 The initial addition of deionized water should be 50-150 parts by weight.
[0023] Preferably, in the first step, the solution is placed in a 60°C water bath and stirred at 200–500 rpm for 1–3 hours until the SA is completely dissolved, resulting in a transparent and homogeneous SA solution.
[0024] Preferably, in the first step, the weight of hydroxypropyl cellulose (HPC) is 1 to 5 parts; and the weight of deionized water added in the second step is 50 to 100 parts.
[0025] Preferably, in the first step, the mixture is stirred at room temperature and at a speed of 300-500 rpm for 3-5 hours until the HPC is completely dissolved, resulting in a transparent and viscous HPC solution.
[0026] Preferably, in the second step, the SA solution is 10-30 parts by weight, the HPC solution is 10-30 parts by weight, and the poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) aqueous dispersion is 1-10 parts by weight.
[0027] Preferably, in the second step, the mixture is stirred at 300-500 rpm for 15-45 min at room temperature to obtain a uniformly dispersed composite precursor solution.
[0028] Preferably, in the third step, after being directionally frozen with liquid nitrogen, the material is taken out and then freeze-dried for 24 hours to obtain a porous SA / HPC-PEDOT:PSS framework with an internal vertical orientation / external radial gradient structure.
[0029] Preferably, in the fourth step, the weight parts of anhydrous calcium chloride are 1 to 5 parts, the weight parts of water are 50 to 100 parts, and the weight parts of ethanol are 20 to 60 parts.
[0030] Preferably, in the fourth step, the material is soaked and crosslinked for 5-10 hours, then soaked in deionized water for 24 hours to remove unreacted raw materials and obtain an SA / HPC-PEDOT:PSS gel evaporator with vertically oriented channels and radial gradient structure.
[0031] The present invention achieves the following technical effects compared to the prior art:
[0032] (1) The present invention constructs a radially gradient layered channel through freezing technology, forming a continuous pore and humidity gradient from the outside to the inside, which significantly improves the efficiency of capillary water transport and steam diffusion, optimizes the heat flow distribution, and inhibits the diffusion of heat into the bulk water.
[0033] (2) In this invention, sodium alginate is cross-linked with calcium ions to form a network, which blocks the migration of salt ions to the evaporation interface and prevents salt crystals from clogging the pores.
[0034] (3) The PEDOT:PSS of the present invention, as a photothermal component, endows the material with excellent solar energy absorption and photothermal conversion performance;
[0035] (4) The process of this invention is simple and the structure is adjustable, making it suitable for fields such as high-salt seawater desalination and industrial wastewater evaporation and concentration. Attached Figure Description
[0036] Figure 1 Morphological characterization of the SA / HPC-PEDOT:PSS gel evaporator with vertically oriented channels and gradient radial structure in this invention. (A) Optical photograph of the cross section of the gel evaporator; (B) Optical photograph of the longitudinal section of the gel evaporator: (C1, C2) are SEM images of the edge region of the cross section at different magnifications; (D1, D2) are SEM images of the central region of the cross section at different magnifications; (E1, E2) are SEM images of the non-central region of the longitudinal section at different magnifications; (F1, F2) are SEM images of the central region of the longitudinal section at different magnifications.
[0037] Figure 2 For different materials in this invention at 1 kW·m -2 The mass change curve under illumination (a) and the corresponding evaporation rate and photothermal conversion efficiency (b);
[0038] Figure 3 For different materials in this invention at 1 kW·m -2 Infrared photographs (a) and surface temperature change curves (b) of the gel evaporator surface under illumination;
[0039] in, Figure 2 and Figure 3SA / HPC-PEDOT:PSS-V is a gel evaporator with only a vertically oriented channel structure; SA / HPC-PEDOT:PSS is a gel evaporator with both vertically oriented channels and a gradient radial structure. Detailed Implementation
[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0041] This invention discloses a method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure, comprising the following steps:
[0042] Step 1: Preparation of sodium alginate (SA) solution and hydroxypropyl cellulose (HPC) solution
[0043] Weigh out sodium alginate (SA), add it to deionized water, place it in a water bath, and stir until SA is completely dissolved to obtain a clear and homogeneous SA solution.
[0044] Weigh out hydroxypropyl cellulose (HPC), add deionized water, and stir at room temperature until the HPC is completely dissolved to obtain a transparent and viscous HPC solution.
[0045] Step 2: Preparation of the composite precursor solution
[0046] Measure the SA solution and HPC solution obtained in step 1, stir and mix them evenly, then add poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate PEDOT:PSS aqueous dispersion, stir at room temperature to obtain a uniformly dispersed composite precursor solution.
[0047] Step 3: Radial freeze forming and freeze drying
[0048] The precursor solution obtained in step 2 is injected into a radial freezing mold, and after being subjected to liquid nitrogen directional freezing treatment, it is taken out and then freeze-dried to obtain an SA / HPC-PEDOT:PSS porous framework with an internal vertical orientation / external radial gradient structure.
[0049] Step 4: Ion crosslinking and curing
[0050] The porous framework obtained in step 3 is immersed in a mixed solution of anhydrous calcium chloride, water and ethanol for cross-linking, and then immersed in deionized water to remove unreacted raw materials, thus obtaining an SA / HPC-PEDOT:PSS gel evaporator with vertically oriented channels and radial gradient structure.
[0051] The quantity of material taken is referred to as "parts" by weight.
[0052] In the first step, the sodium alginate (SA) is 1-5 parts by weight, and the molecular weight of sodium alginate (SA) is 2.0 × 10⁻⁶. 5 g·mol -1 The initial addition of deionized water should be 50-150 parts by weight.
[0053] In the first step, place the solution in a 60°C water bath and stir at 200–500 rpm for 1–3 hours until the SA is completely dissolved, resulting in a transparent and homogeneous SA solution.
[0054] In the first step, the weight of hydroxypropyl cellulose (HPC) is 1 to 5 parts; in the second step, the weight of deionized water is 50 to 100 parts.
[0055] In the first step, the mixture is stirred at room temperature and at a speed of 300-500 rpm for 3-5 hours until the HPC is completely dissolved, resulting in a transparent and viscous HPC solution.
[0056] In the second step, the SA solution is 10-30 parts by weight, the HPC solution is 10-30 parts by weight, and the poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) aqueous dispersion is 1-10 parts by weight.
[0057] In the second step, the mixture is stirred at 300-500 rpm for 15-45 minutes at room temperature to obtain a uniformly dispersed composite precursor solution.
[0058] In the third step, the material is removed after being directionally frozen with liquid nitrogen and then freeze-dried for 24 hours to obtain a porous SA / HPC-PEDOT:PSS framework with an internal vertical orientation / external radial gradient structure.
[0059] In the fourth step, the weight of anhydrous calcium chloride is 1 to 5 parts, the weight of water is 50 to 100 parts, and the weight of ethanol is 20 to 60 parts.
[0060] In the fourth step, the material is soaked and crosslinked for 5-10 hours, and then soaked in deionized water for 24 hours to remove unreacted raw materials, thus obtaining an SA / HPC-PEDOT:PSS gel evaporator with vertically oriented channels and radial gradient structure.
[0061] Example 1:
[0062] Step 1: Preparation of sodium alginate (SA) solution and hydroxypropyl cellulose (HPC) solution
[0063] Weigh out 1 part of sodium alginate (SA, molecular weight approximately 2.0 × 10⁻⁶). 5g·mol -1 Add 50 parts of deionized water, place in a 60°C water bath, and stir at 200 rpm for 1 hour until SA is completely dissolved to obtain a transparent and homogeneous SA solution.
[0064] Weigh 2 parts of hydroxypropyl cellulose (HPC) and add 50 parts of deionized water. Stir at 300 rpm for 3 hours at room temperature until the HPC is completely dissolved, resulting in a transparent and viscous HPC solution.
[0065] Step 2: Preparation of the composite precursor solution
[0066] Take 10 parts of the SA solution and 10 parts of the HPC solution obtained in step 1 and mix them evenly. Then add 1 part of poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) aqueous dispersion and stir at 300 rpm for 15 min at room temperature to obtain a uniformly dispersed composite precursor solution.
[0067] Step 3: Radial freeze forming and freeze drying
[0068] The precursor solution obtained in step 2 was injected into a radial freezing mold, and after being subjected to liquid nitrogen directional freezing treatment, it was taken out and then freeze-dried for 24 hours to obtain a porous SA / HPC-PEDOT:PSS framework with an internal vertical orientation / external radial gradient structure.
[0069] Step 4: Ion crosslinking and curing
[0070] The porous framework obtained in step 3 was immersed in a mixed solution prepared by 1 part anhydrous calcium chloride, 50 parts water and 20 parts ethanol for 5 hours for crosslinking, and then immersed in deionized water for 24 hours to remove unreacted raw materials, thus obtaining an SA / HPC-PEDOT:PSS gel evaporator with vertically oriented channels and radial gradient structure.
[0071] Example 2:
[0072] Step 1: Preparation of sodium alginate (SA) solution and hydroxypropyl cellulose (HPC) solution
[0073] Weigh out 2 portions of sodium alginate (SA, molecular weight approximately 2.0 × 10⁻⁶). 5 g·mol -1 Add 75 parts of deionized water, place in a 60°C water bath, and stir at 300 rpm for 1.5 hours until SA is completely dissolved to obtain a transparent and homogeneous SA solution.
[0074] Weigh 2 parts of hydroxypropyl cellulose (HPC) and add 60 parts of deionized water. Stir at 350 rpm for 3.5 h at room temperature until the HPC is completely dissolved to obtain a transparent and viscous HPC solution.
[0075] Step 2: Preparation of the composite precursor solution
[0076] Take 15 parts of the SA solution and 15 parts of the HPC solution obtained in step 1 and mix them evenly. Then add 3 parts of poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) aqueous dispersion and stir at 350 rpm for 25 min at room temperature to obtain a uniformly dispersed composite precursor solution.
[0077] Step 3: Radial freeze forming and freeze drying
[0078] The precursor solution obtained in step 2 was injected into a radial freezing mold, and after being subjected to liquid nitrogen directional freezing treatment, it was taken out and then freeze-dried for 24 hours to obtain a porous SA / HPC-PEDOT:PSS framework with an internal vertical orientation / external radial gradient structure.
[0079] Step 4: Ion crosslinking and curing
[0080] The porous framework obtained in step 3 was immersed in a mixed solution prepared by 2 parts anhydrous calcium chloride, 60 parts water and 30 parts ethanol for 6 hours for crosslinking, and then immersed in deionized water for 24 hours to remove unreacted raw materials, thus obtaining an SA / HPC-PEDOT:PSS gel evaporator with vertically oriented channels and radial gradient structure.
[0081] Example 3:
[0082] Step 1: Preparation of sodium alginate (SA) solution and hydroxypropyl cellulose (HPC) solution
[0083] Weigh out 3 portions of sodium alginate (SA, molecular weight approximately 2.0 × 10⁻⁶). 5 g·mol -1 Add 100 parts of deionized water, place in a 60℃ water bath, and stir at 350 rpm for 2 hours until SA is completely dissolved to obtain a transparent and homogeneous SA solution.
[0084] Weigh 3 parts of hydroxypropyl cellulose (HPC) and add 70 parts of deionized water. Stir at 400 rpm for 4 hours at room temperature until the HPC is completely dissolved, resulting in a transparent and viscous HPC solution.
[0085] Step 2: Preparation of the composite precursor solution
[0086] Take 20 parts of the SA solution and 20 parts of the HPC solution obtained in step 1 and mix them evenly. Then add 5 parts of poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) aqueous dispersion and stir at 400 rpm for 35 min at room temperature to obtain a uniformly dispersed composite precursor solution.
[0087] Step 3: Radial freeze forming and freeze drying
[0088] The precursor solution obtained in step 2 was injected into a radial freezing mold, and after being subjected to liquid nitrogen directional freezing treatment, it was taken out and then freeze-dried for 24 hours to obtain a porous SA / HPC-PEDOT:PSS framework with an internal vertical orientation / external radial gradient structure.
[0089] Step 4: Ion crosslinking and curing
[0090] The porous framework obtained in step 3 was immersed in a mixed solution prepared by 3 parts anhydrous calcium chloride, 70 parts water and 40 parts ethanol for 7 hours of crosslinking, and then immersed in deionized water for 24 hours to remove unreacted raw materials, thus obtaining an SA / HPC-PEDOT:PSS gel evaporator with vertically oriented channels and radial gradient structure.
[0091] Example 4:
[0092] Step 1: Preparation of sodium alginate (SA) solution and hydroxypropyl cellulose (HPC) solution
[0093] Weigh out 4 portions of sodium alginate (SA, molecular weight approximately 2.0 × 10⁻⁶). 5 g·mol -1 Add 125 parts of deionized water, place in a 60℃ water bath, and stir at 400 rpm for 2.5 hours until SA is completely dissolved to obtain a transparent and homogeneous SA solution.
[0094] Weigh 4 parts of hydroxypropyl cellulose (HPC) and add 80 parts of deionized water. Stir at 450 rpm for 4 hours at room temperature until the HPC is completely dissolved, resulting in a transparent and viscous HPC solution.
[0095] Step 2: Preparation of the composite precursor solution
[0096] Take 25 parts of the SA solution and 25 parts of the HPC solution obtained in step 1 and mix them evenly. Then add 7 parts of poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) aqueous dispersion and stir at 450 rpm for 40 min at room temperature to obtain a uniformly dispersed composite precursor solution.
[0097] Step 3: Radial freeze forming and freeze drying
[0098] The precursor solution obtained in step 2 was injected into a radial freezing mold, and after being subjected to liquid nitrogen directional freezing treatment, it was taken out and then freeze-dried for 24 hours to obtain a porous SA / HPC-PEDOT:PSS framework with an internal vertical orientation / external radial gradient structure.
[0099] Step 4: Ion crosslinking and curing
[0100] The porous framework obtained in step 3 was immersed in a mixed solution prepared by 4 parts anhydrous calcium chloride, 80 parts water and 50 parts ethanol for 8.5 h of crosslinking, and then immersed in deionized water for 24 h to remove unreacted raw materials, thus obtaining an SA / HPC-PEDOT:PSS gel evaporator with vertically oriented channels and radial gradient structure.
[0101] Example 5:
[0102] Step 1: Preparation of sodium alginate (SA) solution and hydroxypropyl cellulose (HPC) solution
[0103] Weigh out 5 portions of sodium alginate (SA, molecular weight approximately 2.0 × 10⁻⁶). 5 g·mol -1 Add 150 parts of deionized water, place in a 60°C water bath, and stir at 500 rpm for 3 hours until SA is completely dissolved, resulting in a transparent and homogeneous SA solution.
[0104] Weigh 5 parts of hydroxypropyl cellulose (HPC) and add 100 parts of deionized water. Stir at 500 rpm for 5 hours at room temperature until the HPC is completely dissolved, resulting in a transparent and viscous HPC solution.
[0105] Step 2: Preparation of the composite precursor solution
[0106] Take 30 parts of the SA solution and 30 parts of the HPC solution obtained in step 1 and mix them evenly. Then add 10 parts of poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) aqueous dispersion and stir at 500 rpm for 45 min at room temperature to obtain a uniformly dispersed composite precursor solution.
[0107] Step 3: Radial freeze forming and freeze drying
[0108] The precursor solution obtained in step 2 was injected into a radial freezing mold, and after being subjected to liquid nitrogen directional freezing treatment, it was taken out and then freeze-dried for 24 hours to obtain a porous SA / HPC-PEDOT:PSS framework with an internal vertical orientation / external radial gradient structure.
[0109] Step 4: Ion crosslinking and curing
[0110] The porous framework obtained in step 3 was immersed in a mixed solution prepared by 5 parts anhydrous calcium chloride, 100 parts water and 60 parts ethanol for 10 hours for crosslinking, and then immersed in deionized water for 24 hours to remove unreacted raw materials, thus obtaining an SA / HPC-PEDOT:PSS gel evaporator with vertically oriented pores and radial gradient structure.
[0111] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the technical scope of the present invention. Therefore, any minor modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.
Claims
1. A method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure, characterized in that, Includes the following steps: Step 1: Preparation of sodium alginate (SA) solution and hydroxypropyl cellulose (HPC) solution Weigh out sodium alginate (SA), add it to deionized water, place it in a water bath, and stir until SA is completely dissolved to obtain a clear and homogeneous SA solution. Weigh out hydroxypropyl cellulose (HPC), add deionized water, and stir at room temperature until the HPC is completely dissolved to obtain a transparent and viscous HPC solution. Step 2: Preparation of the composite precursor solution Measure the SA solution and HPC solution obtained in step 1, stir and mix them evenly, then add poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate PEDOT:PSS aqueous dispersion, stir at room temperature to obtain a uniformly dispersed composite precursor solution. Step 3: Radial freeze forming and freeze drying The precursor solution obtained in step 2 is injected into a radial freezing mold, and after being subjected to liquid nitrogen directional freezing treatment, it is taken out and then freeze-dried to obtain an SA / HPC-PEDOT:PSS porous framework with an internal vertical orientation / external radial gradient structure. Step 4: Ion crosslinking and curing The porous framework obtained in step 3 is immersed in a mixed solution of anhydrous calcium chloride, water and ethanol for cross-linking, and then immersed in deionized water to remove unreacted raw materials, thus obtaining an SA / HPC-PEDOT:PSS gel evaporator with vertically oriented channels and radial gradient structure. The quantity of material taken is referred to as "parts" by weight.
2. The method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure according to claim 1, characterized in that, In the first step, the sodium alginate (SA) is 1-5 parts by weight, and the molecular weight of sodium alginate (SA) is 2.0 × 10⁻⁶. 5 g·mol -1 The initial addition of deionized water should be 50-150 parts by weight.
3. The method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure according to claim 1, characterized in that, In the first step, the solution is placed in a 60°C water bath and stirred at 200–500 rpm for 1–3 hours until the SA is completely dissolved, resulting in a transparent and homogeneous SA solution.
4. The method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure according to claim 1, characterized in that, In the first step, the weight of hydroxypropyl cellulose (HPC) is 1 to 5 parts; in the second step, the weight of deionized water is 50 to 100 parts.
5. The method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure according to claim 1, characterized in that, In the first step, the mixture is stirred at room temperature and at a speed of 300-500 rpm for 3-5 hours until the HPC is completely dissolved, resulting in a transparent and viscous HPC solution.
6. The method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure according to claim 1, characterized in that, In the second step, the SA solution is 10-30 parts by weight, the HPC solution is 10-30 parts by weight, and the poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) aqueous dispersion is 1-10 parts by weight.
7. The method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure according to claim 1, characterized in that, In the second step, the mixture is stirred at 300-500 rpm for 15-45 minutes at room temperature to obtain a uniformly dispersed composite precursor solution.
8. The method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure according to claim 1, characterized in that, In the third step, after being directionally frozen with liquid nitrogen, the sample is taken out and then freeze-dried for 24 hours to obtain a porous SA / HPC-PEDOT:PSS framework with an internal vertical orientation / external radial gradient structure.
9. The method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure according to claim 1, characterized in that, In the fourth step, the weight parts of anhydrous calcium chloride are 1 to 5 parts, the weight parts of water are 50 to 100 parts, and the weight parts of ethanol are 20 to 60 parts.
10. The method for preparing a gel evaporator with vertically oriented channels and a radial gradient structure according to claim 1, characterized in that, In the fourth step, the material is soaked and crosslinked for 5-10 hours, and then soaked in deionized water for 24 hours to remove unreacted raw materials, thereby obtaining an SA / HPC-PEDOT:PSS gel evaporator with vertically oriented channels and radial gradient structure.