| 研究課題/領域番号 |
22KF0387
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| 補助金の研究課題番号 |
22F22366 (2022)
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| 研究種目 |
特別研究員奨励費
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| 配分区分 | 基金 (2023)
補助金 (2022) |
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| 応募区分 | 外国 |
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| 審査区分 |
小区分27030:触媒プロセスおよび資源化学プロセス関連
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| 研究機関 | 国立研究開発法人物質・材料研究機構 |
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研究代表者 |
押切 光丈 国立研究開発法人物質・材料研究機構, ナノアーキテクトニクス材料研究センター, 主幹研究員 (20354368)
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| 研究分担者 |
LI SIJIE 国立研究開発法人物質・材料研究機構, ナノアーキテクトニクス材料研究センター, 外国人特別研究員
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| 研究期間 (年度) |
2023-03-08 – 2025-03-31
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| 研究課題ステータス |
交付 (2023年度)
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| 配分額 *注記 |
2,100千円 (直接経費: 2,100千円)
2024年度: 1,000千円 (直接経費: 1,000千円)
2023年度: 700千円 (直接経費: 700千円)
2022年度: 400千円 (直接経費: 400千円)
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| キーワード | photoelectrocatalysis / carbon dioxide reduction / silicon photocathode / photoanode / cocatalysts / surface and interface |
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| 研究開始時の研究の概要 |
This project focus on the development of heterogeneous Si-based photocathodes (PC) for solar-driven CO2 reduction by surface/interface modification, and then assembly of photoelectrochemical (PEC) devices by coupling optimized Si-based PC and potential photoanode (PA) to complete the synergistic reaction of CO2 reduction and water oxidation to further prepare high-value chemicals.
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| 研究実績の概要 |
In the past year, we developed a one-step method for liquid-phase in-situ growth of Ag nanoparticle cocatalysts on p-type planar Si semiconductors to fabricate photocathodes for photoelectrochemical (PEC) CO2 reduction. Directly using planar Si is beneficial to shortening the photoelectrode manufacturing process. Besides, this method can effectively control the size and distribution of the Ag nanoparticles through the Ag ion concentration and growth time. By regulating the structure and active sites of Ag cocatalysts supported on the planar Si substrates as photocathodes and evaluating their performance of reducing CO2 to syngas, the Faradaic efficiency for CO at the optimal Ag/Si photocathode is increased by 6.2 times at -0.4 V vs. RHE (reversible hydrogen electrode). This shows that the PEC CO2 reduction performance of Si-based photocathodes is closely associated with the structure and property of the cocatalyst.
Furthermore, we prepared porous nanostructured BiVO4 with n-type semiconductor properties as a potential photoanode to assist PEC CO2 reduction. In addition to analyzing the chemical composition and physical structural properties of the as-prepared BiVO4 semiconductor, we also proceed to deposit transition metal cocatalysts on the BiVO4 photoanode. By designing and optimizing the preparation parameters of the transition metal cocatalyst and the surface/interface construction between the cocatalyst and BiVO4, the photocurrent density of BiVO4 as a photoanode for water oxidation reaction has been significantly improved.
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| 現在までの達成度 (区分) |
現在までの達成度 (区分)
2: おおむね順調に進展している
理由
Based on the in-situ deposition and growth of Ag nanoparticles on Si under normal temperature and liquid phase conditions, we constructed a controllable Si-based photocathode for PEC CO2 reduction. By analyzing the PEC properties of Ag/Si photocathodes, it is found that the PEC CO2 reduction efficiency and selectivity are closely related to the Si surface modification and the interface structure of Si semiconductor/Ag cocatalyst. In the PEC CO2 reduction performance evaluation, the Ag/Si photocathode can increase the Faradaic efficiency for CO by 6.2 times under light irradiation. In addition, transition metal cocatalyst-modified BiVO4 photoanodes have also made progress, and the photocurrent density has been significantly improved in water oxidation performance tests. This shows that we have made smooth progress in the preparation of the Si-based photocathode and BiVO4 photoanode. It is believed that with the assistance of BiVO4 water oxidation photoanode, a Si-based photocathode can be manufactured to achieve efficient and operable PEC CO2 reduction.
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| 今後の研究の推進方策 |
In the future, we will continue to explore the surface/interface engineering of p-type Si-based semiconductors to prepare PEC CO2 photocathodes. By matching n-type semiconductors with appropriate band structures to form p-n heterojunctions, we aim to further improve the selectivity and efficiency of CO2 reduction. In addition, we will continue to focus on the optimization of n-type BiVO4 photoanodes for water oxidation, focusing on further increasing photocurrent density and reducing onset potential. Ultimately, bias-free CO2 reduction will be constructed by combining high-performance p-type Si semiconductor photocathode and n-type BiVO4 semiconductor photoanode.
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