Preparation method of hydrophilic electrode and application of hydrophilic electrode in interface water photoelectric conversion

Abstract

The invention relates to a preparation method of a hydrophilic electrode and application of the hydrophilic electrode in interface water photoelectric conversion, and belongs to the field of interface water photoelectric conversion. According to the preparation method of the hydrophilic electrode, a BiOI / TiO2 TNAs composite electrode with strong hydrophilicity is prepared through a continuous ion layer adsorption reaction method, and narrow-band-gap BiOI and TiO2 TNAs are compounded to form a heterojunction, so that the light response range is widened, the forbidden band width is reduced, the separation efficiency of photon-generated carriers is improved, and energy conversion among light, water and electricity is promoted. According to the invention, the interface water generated on the hydrophilic surface is used as a proton semiconductor, and the BiOI / TiO2 composite electrode with strong hydrophilicity is prepared, so that the thickness of the generated interface water is increased, the resistivity of the water is reduced, the energy conversion efficiency among light, water and electricity is improved, and the performance of the interface water photoelectric conversion device is enhanced. The open-circuit voltage of the single interface water solar cell assembled based on the special photoelectric property of the interface water can reach hundreds of millivolts, the short-circuit current can reach tens of microamperes, and the single interface water solar cell can work stably.

Description

Technical Field

[0001] This invention belongs to the field of interfacial water-photovoltaic conversion, specifically relating to a method for preparing a hydrophilic electrode and its application in interfacial water-photovoltaic conversion. Background Technology

[0002] Water is a natural energy absorber, energy storage device, energy transducer, and energy transmitter. Studies indicate that the water bodies covering 70% of the Earth's surface can absorb approximately 10... 15 Hydropower can convert solar energy into various forms of energy, including heat, kinetic energy, and mechanical energy. However, existing hydropower conversion technologies still face numerous challenges in practical applications. For example, while underwater acoustic and electro-electric transducers perform well in underwater communication and detection, their energy conversion efficiency is limited, and they rely on external electrical input, making energy self-sufficiency difficult. Pumped storage technology, while highly efficient, is limited by geographical conditions and high construction costs, and energy conversion involves losses. Piezoelectric and magnetostrictive transducers, capable of converting mechanical and electrical energy, have their energy conversion efficiency limited by material properties, and their complex structures and high costs further complicate matters. Fiber optic hydrophones and composite rod transducers, while highly sensitive and resistant to interference, lack sufficient energy self-sufficiency, making continuous operation in unattended environments challenging. Therefore, existing hydropower utilization technologies still need improvement in terms of energy self-sufficiency, conversion efficiency, and environmental adaptability.

[0003] Studies indicate that the diffusion rates of hydrogen and hydroxide ions are similar to those of electrons. The self-dissociation process of water molecules can be viewed as an electron / hole separation process in electronic semiconductor materials, meaning that water is a proton semiconductor material similar to electronic semiconductors. However, bulk water has extremely low light absorption and high resistivity, and the self-dissociated hydrogen and hydroxide ions readily recombine to form water. Therefore, using bulk water as a proton semiconductor for photoelectric conversion devices results in extremely low conversion efficiency, making practical applications impossible. Research over the past two decades has revealed that interfacial water generated on the surface of hydrophilic solid materials possesses many unique properties different from bulk water. For example, it carries a charge, has a much lower conductivity than bulk water, exhibits a 270 nm ultraviolet characteristic absorption, fluoresces upon excitation, and its interfacial water film thickness increases significantly after illumination. This suggests that interfacial water possesses the unique property of converting solar energy into electrical energy. Therefore, using interfacial water generated on hydrophilic surfaces as a proton semiconductor to achieve energy conversion between light, water, and electricity is not only beneficial for broadening the application fields of existing water energy utilization technologies, but also helps to develop truly green and clean photovoltaic power generation technologies throughout the entire process, thus achieving sustainable development of human society.

[0004] Currently, the interfacial water-to-electricity conversion device that utilizes hydrophilic electrodes often uses titanium dioxide (TiO2) electrodes, which have strong hydrophilicity. However, TiO2 has a large band gap and low surface carrier mobility, which greatly restricts the energy conversion between light, water and electricity. Summary of the Invention

[0005] The purpose of this invention is to increase the thickness of the interfacial water generated by the hydrophilic electrode and improve the performance of the interfacial water photoelectric conversion device. It provides a method for preparing a hydrophilic electrode and its application in interfacial water photoelectric conversion. A BiOI / TiO2TNAs composite electrode with strong hydrophilicity is prepared by a continuous ion layer adsorption reaction method. The narrow bandgap BiOI (bandgap width of 1.75 eV) is combined with TiO2TNAs to form a heterojunction, which broadens the photoresponse range, reduces the bandgap width, improves the separation efficiency of photogenerated carriers, and promotes the energy conversion between light, water and electricity.

[0006] To achieve the above objectives, the technical solution of the present invention is: a method for preparing a hydrophilic electrode, wherein a BiOI / TiO2TNAs composite electrode with strong hydrophilicity is prepared by a continuous ion layer adsorption reaction method, and the narrow bandgap BiOI and TiO2TNAs are combined to form a heterojunction, thereby broadening the photoresponse range, reducing the bandgap, improving the separation efficiency of photogenerated carriers, and promoting the energy conversion between light, water and electricity.

[0007] Furthermore, the method includes:

[0008] The cleaned FTO conductive glass is subjected to ozone treatment with the conductive side facing up for 20 minutes.

[0009] Place the FTO conductive glass with the conductive side facing down inside the reactor;

[0010] A rutile phase titanium dioxide nanorod film was prepared on the surface of FTO conductive glass using a hydrothermal method, thus obtaining a TiO2TNAs electrode.

[0011] A BiOI / TiO2TNAs composite electrode with strong hydrophilicity was prepared by using a continuous ion layer adsorption reaction method and controlling the number of depositions.

[0012] Furthermore, the FTO conductive glass was ultrasonically cleaned in acetone, anhydrous ethanol, and deionized water for 20 minutes in sequence. The water contact angle of the cleaned FTO conductive glass was 38.1°.

[0013] Furthermore, a heat-resistant tape with a width of 0.5 cm is applied to the conductive surface of the FTO conductive glass to prevent the growth of rod-shaped arrays in that area.

[0014] Furthermore, the FTO conductive glass was moved with the conductive side facing down and placed inside the 100 mL reactor liner.

[0015] Furthermore, a rutile phase titanium dioxide nanorod film was prepared on the surface of FTO conductive glass using a hydrothermal method, thus obtaining a TiO2TNAs electrode. The specific method is as follows:

[0016] Mix 20 mL of hydrochloric acid and 20 mL of deionized water in a 100 mL beaker. Seal the mouth of the beaker with plastic wrap to prevent the hydrochloric acid from evaporating into the air, and stir on a magnetic stirrer for 3 min. After stirring, add tetrabutyl titanate to the beaker, reseal with plastic wrap, and stir on a magnetic stirrer for 30 min.

[0017] The solution, after stirring for 30 min, was poured into a reactor liner lined with FTO conductive glass and subjected to hydrothermal reaction at 150 ℃ for 8 h. After the reaction was completed, the electrode was removed after cooling. The surface was first cleaned with anhydrous ethanol, and then rinsed with deionized water to remove residual reactants. Subsequently, it was transferred to an oven and dried at 50 ℃ to obtain the FTO-TiO2TNAs electrode, i.e., the TiO2TNAs electrode, with a contact angle of 25.9°.

[0018] Furthermore, a BiOI / TiO2TNAs composite electrode with strong hydrophilicity was prepared by utilizing a continuous ion layer adsorption reaction method and controlling the number of depositions. The specific method is as follows:

[0019] The prepared TiO2TNAs electrode was immersed in a 0.05 mol / L bismuth nitrate solution for 1 min, so that Bi... 3+ The Bi2O3 was adsorbed onto the membrane surface, and then the electrode surface was rinsed with deionized water for 15 seconds to remove unadsorbed Bi2O3. 3+ Next, the electrode is immersed in a 0.05 mol / L potassium iodide solution for 1 min to allow KI and Bi to react. 3+ A reaction occurs, depositing BiOI on the surface of the TiO2TNAs electrode. The electrode is then rinsed with deionized water for 10 seconds. This process constitutes one deposition. By controlling the number of depositions, BiOI / TiO2TNAs composite electrodes with different hydrophilicities can be obtained.

[0020] Furthermore, the BiOI / TiO2 composite electrode with 6 deposition cycles had the smallest water contact angle, at 8.2°.

[0021] The present invention also provides an application of a hydrophilic electrode prepared by the above-described method in interfacial water photoelectric conversion, and an interfacial water photoelectric conversion device is assembled based on a BiOI / TiO2TNAs composite electrode.

[0022] Furthermore, based on the BiOI / TiO2TNAs composite electrode, an interfacial water-photovoltaic conversion device was assembled, and the specific assembly method is as follows:

[0023] Using a BiOI / TiO2TNAs composite electrode as the photoanode and FTO conductive glass as the counter electrode, a 150 μm thick plastic sheet is placed between the two electrodes to control the amount of deionized water, thus assembling a sandwich-structured interfacial water solar cell, i.e., an interfacial water photoelectric conversion device.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) The preparation process of the strongly hydrophilic BiOI / TiO2 composite electrode is simple, easy to operate, inexpensive and highly stable;

[0026] (2) Compared with TiO2 hydrophilic photoanode, the overall output performance of the interface water-photoelectric conversion device is significantly enhanced after replacing TiO2 photoanode with BiOI / TiO2TNAs composite photoanode;

[0027] (3) The working medium of the interface water-photovoltaic conversion device based on BiOI / TiO2TNAs composite electrode is water, which is extremely abundant. The device can be deployed wherever there is water (such as reservoirs, lakes, oceans, etc.) without occupying valuable land resources, and has the potential for large-scale application.

[0028] (4) Interface water solar cells are not only green and clean in the photoelectric conversion process, but also basically do not produce byproducts that are harmful to the human body or the environment in the process of device preparation, assembly and disposal. They have a very low impact on human society and the ecological environment and can effectively solve the environmental pollution problems caused by photovoltaic materials and devices in the production and disposal process in existing photovoltaic power generation technologies. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the sandwich structure interface water photoelectric conversion device of the present invention; in the figure, 1-hydrophilic electrode, 2-counter electrode, 3-bulk water and 4-interfacial water.

[0030] Figure 2 The figure shows the characterization results of the BiOI / TiO2TNAs composite electrode of the present invention; in the figure, (a) is the XRD pattern and (b) is the SEM image.

[0031] Figure 3 The values ​​represent the open-circuit voltage and short-circuit current of the interface water-photovoltaic conversion device after 5 minutes of illumination.

[0032] Figure 4 These are results from outdoor experiments (actual outdoor light intensity is approximately 400~800 W / m²).2 ). Detailed Implementation

[0033] The technical solution of the present invention will now be described in detail with reference to the accompanying drawings.

[0034] This invention provides a method for preparing a hydrophilic electrode. A strongly hydrophilic BiOI / TiO2TNAs composite electrode is prepared via a continuous ion-layer adsorption reaction. The narrow-bandgap BiOI and TiO2TNAs are combined to form a heterojunction, broadening the photoresponse range, reducing the bandgap, improving the separation efficiency of photogenerated carriers, and promoting energy conversion between light, water, and electricity. The method includes:

[0035] The cleaned FTO conductive glass is subjected to ozone treatment with the conductive side facing up for 20 minutes.

[0036] Place the FTO conductive glass with the conductive side facing down inside the reactor;

[0037] A rutile phase titanium dioxide nanorod film was prepared on the surface of FTO conductive glass using a hydrothermal method, thus obtaining a TiO2TNAs electrode.

[0038] A BiOI / TiO2TNAs composite electrode with strong hydrophilicity was prepared by using a continuous ion layer adsorption reaction method and controlling the number of depositions.

[0039] This invention also provides an application of a hydrophilic electrode prepared using the above-described method in interfacial water photoelectric conversion, wherein an interfacial water photoelectric conversion device is assembled based on a BiOI / TiO2TNAs composite electrode. The assembly method is as follows:

[0040] Using a BiOI / TiO2TNAs composite electrode as the photoanode and FTO conductive glass as the counter electrode, a 150 μm thick plastic sheet is placed between the two electrodes to control the amount of deionized water, thus assembling a sandwich-structured interfacial water solar cell, i.e., an interfacial water photoelectric conversion device.

[0041] The following is a detailed implementation process of the present invention.

[0042] (1) Preparation of TiO2 hydrophilic electrodes (anatase phase and rutile phase) and BiOI / TiO2TNAs hydrophilic electrodes

[0043] The FTO conductive glass was sequentially ultrasonically cleaned in acetone, anhydrous ethanol, and deionized water for 20 minutes each. The water contact angle of the cleaned FTO was 38.1°. During the 10-minute observation period, FTO did not generate exclusion-zone water (EZ) in the 10 mg / L nano carbon black particle solution.

[0044] (a) Anatase TiO2 hydrophilic electrode

[0045] Titanium acetylacetonate was dissolved in n-butanol to prepare a 0.25 mol / L titanium dioxide precursor solution. Then, the titanium dioxide precursor solution was spin-coated onto a cleaned FTO conductive glass substrate using a spin-coating method (1500 rpm). The substrate was then calcined at 450 °C for 1 hour to obtain a hydrophilic electrode (FTO-TiO2) coated with anatase-phase nano-titanium dioxide particles, with a contact angle of 9.3°. During a 10-minute observation period, this electrode produced an interfacial water layer (EZ) with a thickness of approximately 120 μm in a 10 mg / L nano-carbon black particle solution.

[0046] (b) Rutile phase TiO2 hydrophilic electrode (TiO2TNAs electrode)

[0047] Mix 20 mL of hydrochloric acid and 20 mL of deionized water in a 100 mL beaker. Seal the beaker with plastic wrap to prevent the hydrochloric acid from evaporating into the air, and stir with a magnetic stirrer for 3 min. After stirring, add tetrabutyl titanate (TBOT, AR) to the beaker, reseal with plastic wrap, and stir with a magnetic stirrer for 30 min. Apply a 0.5 cm wide strip of heat-resistant tape to the conductive side of the cleaned FTO glass to prevent the growth of rod-like arrays in that area. Ozone treat the tape-coated FTO glass, conductive side up, for 20 min to enhance the wettability of the electrode surface. After ozone treatment, place the FTO glass, conductive side down, into the liner of a 100 mL reactor.

[0048] The solution, stirred for 30 min, was poured into a reactor liner lined with FTO conductive glass and subjected to hydrothermal reaction at 150 °C for 8 h. After the reaction, the electrode was cooled and removed. The surface was first cleaned with anhydrous ethanol, then rinsed with deionized water to remove residual reactants. Subsequently, it was transferred to an oven and dried at 50 °C to obtain the FTO-TiO2TNAs electrode (i.e., the TiO2TNAs electrode), with a contact angle of 25.9°. During a 10 min observation period, this electrode produced an interfacial water layer (EZ) approximately 100 μm thick in a 10 mg / L nano-carbon black particle solution.

[0049] (c) BiOI / TiO2TNAs composite electrode

[0050] The prepared TiO2TNAs electrode was immersed in a 0.05 mol / L bismuth nitrate solution for 1 min, so that Bi... 3+ The Bi2O3 was adsorbed onto the membrane surface, and then the electrode surface was rinsed with deionized water for 15 seconds to remove unadsorbed Bi2O3. 3+Next, the electrode is immersed in a 0.05 mol / L potassium iodide solution for 1 min to allow KI and Bi to react. 3+ A reaction occurred, depositing BiOI on the surface of the TiO2TNAs electrode. The electrode was then rinsed with deionized water for 10 s, completing one deposition cycle. By controlling the number of deposition cycles, BiOI / TiO2TNAs composite electrodes with varying hydrophilicity could be obtained. The BiOI / TiO2 composite electrode with six deposition cycles exhibited the smallest water contact angle (8.2°), indicating the best hydrophilicity. During a 10-minute observation period, this electrode produced an interfacial water layer (EZ) approximately 150 μm thick in a 10 mg / L solution of nano-carbon black particles. The SEM and XRD results of the BiOI / TiO2TNAs hydrophilic electrode are shown below. Figure 2 .

[0051] (2) Performance of the interfacial water-photovoltaic conversion device based on BiOI / TiO2TNAs composite electrode

[0052] Using a BiOI / TiO2TNAs composite electrode as the photoanode and the less hydrophilic FTO as the counter electrode, a 150 μm thick plastic sheet was placed between the two electrodes to control the amount of deionized water. This minimized the content of bulk water, which lacks special photoelectric properties, and thus reduced the battery's internal resistance. The resulting assembly yielded the following... Figure 1 The sandwich-structured interface water solar cell shown has an effective contact area of ​​2 cm × 3 cm. Figure 3 As shown, under standard sunlight conditions (1000 W / m²), 2 When the illumination time was 5 minutes, the open-circuit voltage and short-circuit current of the interface water cell assembled based on BiOI / TiO2TNAs stabilized at 0.48 V and 55.6 μA, respectively, while the open-circuit voltages of the anatase phase and rutile phase TiO2 electrodes were only 0.3 V and 0.15 V, and the short-circuit currents were 9.3 and 4.2 μA, respectively, indicating a significant improvement in light-water-electricity conversion efficiency. Furthermore, under actual outdoor illumination conditions, the interface water solar cell, after being connected in series and parallel with multiple modules, enabled the timer to operate stably for more than 1 hour. Figure 4 Furthermore, the voltage and current are stable.

[0053] This invention utilizes interfacial water generated on a hydrophilic surface as a proton semiconductor. By fabricating a highly hydrophilic BiOI / TiO2 composite electrode, the thickness of the generated interfacial water is increased, the resistivity of the water is reduced, and the energy conversion efficiency between light, water, and electricity is improved, thus enhancing the performance of the interfacial water photoelectric conversion device. A single interfacial water solar cell assembled based on the unique photoelectric properties of interfacial water can achieve an open-circuit voltage of hundreds of millivolts and a short-circuit current of tens of microamps. An interfacial water solar cell system assembled with multiple modules in series and parallel can drive an electronic timer to operate stably for more than one hour. Moreover, under actual outdoor lighting conditions, the open-circuit voltage and short-circuit current of the device remain stable.

[0054] The above are preferred embodiments of the present invention. Any changes made to the technical solution of the present invention that do not exceed the scope of the technical solution of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for preparing a hydrophilic electrode, characterized in that, A highly hydrophilic BiOI / TiO2TNAs composite electrode was prepared by a continuous ion layer adsorption reaction method. The narrow bandgap BiOI and TiO2TNAs were combined to form a heterojunction, which broadened the photoresponse range, reduced the bandgap, improved the separation efficiency of photogenerated carriers, and promoted the energy conversion between light, water and electricity.

2. The method for preparing a hydrophilic electrode according to claim 1, characterized in that, include: The cleaned FTO conductive glass is subjected to ozone treatment with the conductive side facing up for 20 minutes. Place the FTO conductive glass with the conductive side facing down inside the reactor; A rutile phase titanium dioxide nanorod film was prepared on the surface of FTO conductive glass using a hydrothermal method, thus obtaining a TiO2TNAs electrode. A BiOI / TiO2TNAs composite electrode with strong hydrophilicity was prepared by using a continuous ion layer adsorption reaction method and controlling the number of depositions.

3. The method for preparing a hydrophilic electrode according to claim 2, characterized in that, The FTO conductive glass was ultrasonically cleaned in acetone, anhydrous ethanol, and deionized water for 20 minutes in sequence. The water contact angle of the cleaned FTO conductive glass was 38.1°.

4. The method for preparing a hydrophilic electrode according to claim 2, characterized in that, A 0.5 cm wide heat-resistant tape is applied to the conductive surface of the FTO conductive glass to prevent the growth of rod-shaped arrays in that area.

5. The method for preparing a hydrophilic electrode according to claim 2, characterized in that, The FTO conductive glass, with its conductive side facing down, was placed inside the 100 mL reactor liner.

6. The method for preparing a hydrophilic electrode according to claim 2, characterized in that, A rutile phase titanium dioxide nanorod film was prepared on the surface of FTO conductive glass using a hydrothermal method, thus obtaining a TiO2TNAs electrode. The specific method is as follows: Mix 20 mL of hydrochloric acid and 20 mL of deionized water in a 100 mL beaker. Seal the mouth of the beaker with plastic wrap to prevent the hydrochloric acid from evaporating into the air, and stir on a magnetic stirrer for 3 min. After stirring, add tetrabutyl titanate to the beaker, reseal with plastic wrap, and stir on a magnetic stirrer for 30 min. The solution, after stirring for 30 min, was poured into the lining of a reactor containing FTO conductive glass and subjected to hydrothermal reaction at 150 ℃ for 8 h. After the reaction was completed, the electrode was removed after cooling. The surface was first cleaned with anhydrous ethanol, and then rinsed with deionized water to remove residual reactants. Subsequently, it was transferred to an oven and dried at 50 ℃ to obtain the FTO-TiO2TNAs electrode, i.e., the TiO2TNAs electrode, with a contact angle of 25.9°.

7. The method for preparing a hydrophilic electrode according to claim 2, characterized in that, A BiOI / TiO2TNAs composite electrode with strong hydrophilicity was prepared by using a continuous ion layer adsorption reaction method and controlling the number of depositions. The specific method is as follows: The prepared TiO2TNAs electrode was immersed in a 0.05 mol / L bismuth nitrate solution for 1 min, so that Bi... 3+ The Bi2O3 was adsorbed onto the membrane surface, and then the electrode surface was rinsed with deionized water for 15 seconds to remove unadsorbed Bi2O3. 3+ Next, the electrode is immersed in a 0.05 mol / L potassium iodide solution for 1 min to allow KI and Bi to react. 3+ A reaction occurs, depositing BiOI on the surface of the TiO2TNAs electrode. The electrode is then rinsed with deionized water for 10 seconds. This process constitutes one deposition. By controlling the number of depositions, BiOI / TiO2TNAs composite electrodes with different hydrophilicities can be obtained.

8. The method for preparing a hydrophilic electrode according to claim 7, characterized in that, The BiOI / TiO2 composite electrode with 6 deposition cycles had the smallest water contact angle, at 8.2°.

9. The application of a hydrophilic electrode prepared by the method described in any one of claims 1-8 in interfacial water-photoelectric conversion, characterized in that, An interfacial water-photovoltaic conversion device was assembled based on a BiOI / TiO2TNAs composite electrode.

10. The application of a hydrophilic electrode according to claim 9 in interfacial water-photovoltaic conversion, characterized in that, An interfacial water-photovoltaic conversion device was assembled based on a BiOI / TiO2TNAs composite electrode. The specific assembly method is as follows: Using a BiOI / TiO2TNAs composite electrode as the photoanode and FTO conductive glass as the counter electrode, a 150 μm thick plastic sheet is placed between the two electrodes to control the amount of deionized water, thus assembling a sandwich-structured interfacial water solar cell, i.e., an interfacial water photoelectric conversion device.

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