112學年材料所-第十一週 專題研討課程 B區演講公告
2023.11.13
112學年上學期 材料所專題研討課程 B區公告
題目：
以顆粒狀光催化劑實現大規模太陽能產氫
題目：
以顆粒狀光催化劑實現大規模太陽能產氫
Large scale solar hydrogen production using particulate photocatalysts
主講人：堂免一成 Kazunari Domen 博士
現職：日本信州大學 能源及環境中心/先銳材料研究所 特聘教授
學歷：國立東京大學 化學所 博士
時間：112年 11月 16日(四) 下午 3:10 – 5 :00
地點：成功大學成功校區材料新館1F 協勝發講堂 教室44101
演講摘要：
Photocatalytic water splitting has been receiving growing interest as a means of producing renewable hydrogen, because systems based on particulate photocatalysts may be spread over large areas through potentially inexpensive processes. A solar hydrogen production system based on 100-m2 arrayed photocatalytic water splitting panels and an oxyhydrogen gas-separation module was built recently, and its performance and system characteristics including safety issues were reported. Nevertheless, it is essential to radically improve the solar-to-hydrogen energy conversion efficiency (STH) of particulate photocatalysts and develop suitable reaction systems. In my talk, recent progress in photocatalytic materials and reaction systems will be presented.
The author’s group has studied various particulate semiconductor materials as photocatalysts for water splitting. The apparent quantum yield (AQY) of overall water splitting using SrTiO3 has been improved to more than 90% at 365 nm, equivalent to an internal quantum efficiency of almost unity, by refining the preparation conditions of the photocatalyst and the loading conditions of cocatalysts. This observation means that particulate photocatalysts can drive the endergonic overall water splitting reaction with almost no recombination loss as in photon-to-chemical conversion processes during the photosynthesis. For practical solar hydrogen production, however, it is essential to develop photocatalysts that are active under visible light. Ta3N5, Y2Ti2O5S2, BaTaO2N, and SrTaO2N were recently shown to be active in photocatalytic overall water splitting via one-step excitation under visible light.
It is also possible to combine hydrogen evolution photocatalysts (HEPs) and oxygen evolution photocatalysts (OEPs) to split water into hydrogen and oxygen via two-step excitation. Such a process is recognized as Z-scheme widely. Particulate photocatalyst sheets consisting of La- and Rh-codoped SrTiO3 as the HEP and Mo-doped BiVO4 as the HEP immobilized onto Au and C layers split water into hydrogen and oxygen with STH values exceeding 1.0%. Some (oxy)chalcogenides and (oxy)nitrides with long absorption edge wavelengths are also applicable to Z-schematic photocatalyst sheets and hold the promise of realizing greater STH values.
主講人：堂免一成 Kazunari Domen 博士
現職：日本信州大學 能源及環境中心/先銳材料研究所 特聘教授
學歷：國立東京大學 化學所 博士
時間：112年 11月 16日(四) 下午 3:10 – 5 :00
地點：成功大學成功校區材料新館1F 協勝發講堂 教室44101
演講摘要：
Photocatalytic water splitting has been receiving growing interest as a means of producing renewable hydrogen, because systems based on particulate photocatalysts may be spread over large areas through potentially inexpensive processes. A solar hydrogen production system based on 100-m2 arrayed photocatalytic water splitting panels and an oxyhydrogen gas-separation module was built recently, and its performance and system characteristics including safety issues were reported. Nevertheless, it is essential to radically improve the solar-to-hydrogen energy conversion efficiency (STH) of particulate photocatalysts and develop suitable reaction systems. In my talk, recent progress in photocatalytic materials and reaction systems will be presented.
The author’s group has studied various particulate semiconductor materials as photocatalysts for water splitting. The apparent quantum yield (AQY) of overall water splitting using SrTiO3 has been improved to more than 90% at 365 nm, equivalent to an internal quantum efficiency of almost unity, by refining the preparation conditions of the photocatalyst and the loading conditions of cocatalysts. This observation means that particulate photocatalysts can drive the endergonic overall water splitting reaction with almost no recombination loss as in photon-to-chemical conversion processes during the photosynthesis. For practical solar hydrogen production, however, it is essential to develop photocatalysts that are active under visible light. Ta3N5, Y2Ti2O5S2, BaTaO2N, and SrTaO2N were recently shown to be active in photocatalytic overall water splitting via one-step excitation under visible light.
It is also possible to combine hydrogen evolution photocatalysts (HEPs) and oxygen evolution photocatalysts (OEPs) to split water into hydrogen and oxygen via two-step excitation. Such a process is recognized as Z-scheme widely. Particulate photocatalyst sheets consisting of La- and Rh-codoped SrTiO3 as the HEP and Mo-doped BiVO4 as the HEP immobilized onto Au and C layers split water into hydrogen and oxygen with STH values exceeding 1.0%. Some (oxy)chalcogenides and (oxy)nitrides with long absorption edge wavelengths are also applicable to Z-schematic photocatalyst sheets and hold the promise of realizing greater STH values.