有效的非牺牲性水分裂通过可见光的两步光激发,使用改性氧化作为进化光催化剂
Kazuhiko Maeda1, Masanobu Higashi, Daling Lu
1Department of Chemical System Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Journal of the American Chemical Society
|April 8, 2010
概括
研究人员开发了一种新的Z模式光催化系统,用于高效的水分. 该系统使用修改后的ZrO(2) / TaON和Pt/WO(3) 与IO(3)(-) /I(-) 反氧介质,在可见光下实现创纪录的和氧生产.
科学领域:
- 材料科学 材料科学 材料科学
- 光催化作用的光催化
- 可再生能源可再生能源是可再生能源.
背景情况:
- 光催化水分解对于可持续的生产至关重要.
- Z-方案系统提供高效的电荷分离,用于增强光催化.
- 开发可见光水分的非牺牲性系统仍然是一个挑战.
研究的目的:
- 为了研究一种新的两步Z图形光催化系统,用于水分裂.
- 确定最佳的光催化剂和氧化还原媒介,以实现高效的H(2) 和O(2) 进化.
- 为了在可见光下以高量子产量实现石度水分裂.
主要方法:
- 使用修改后的ZrO(2) / TaON和Pt/WO(3) 光催化剂制造和表征一个Z模式系统.
- 包括一个IO(3)(-) /I(-) 氧还原介质,以实现高效的电子转移.
- 在可见光照射下评估光催化活性 (420.5nm单色光).
- 光发光和光电化学测量以阐明机制.
主要成果:
- 带有IO(3)(-) /I(-) 介质的Pt/ZrO(2) /TaON和Pt/WO(3) 系统实现了石化水分.
- 获得了6.3%的表面量子收益率,比TaON类似物高6倍.
- 这代表了非牺牲性可见光驱动水分系统的最高报告产量.
- 增强的活性归因于高效的氧化还原媒介反应和抑制的电子孔重组.
结论:
- 开发的Z-scheme系统显示了可见光驱动水分的高效率.
- 修改后的ZrO(2) / TaON表现出温和的n型半导体特性,减少重组.
- 这项工作为高效的太阳能气生产提供了有希望的途径.
相关概念视频
01:26Oxygenic Photosynthesis
Oxygenic photosynthesis is a fundamental process in which light energy is harnessed to drive the oxidation of water, leading to the production of molecular oxygen (O₂), adenosine triphosphate (ATP), and nicotinamide adenine dinucleotide phosphate (NADPH). This process is essential for sustaining aerobic life on Earth and is primarily carried out by cyanobacteria, algae, and plants. The core of oxygenic photosynthesis lies in the thylakoid membranes, where chlorophyll pigments facilitate light...
01:34The Z-Scheme of Electron Transport in Photosynthesis
The light reactions of photosynthesis assume a linear flow of electrons from water to NADP+. During this process, light energy drives the splitting of water molecules to produce oxygen. However, oxidation of water molecules is a thermodynamically unfavorable reaction and requires a strong oxidizing agent. This is accomplished by the first product of light reactions: oxidized P680 (or P680+), the most powerful oxidizing agent known in biology. The oxidized P680 that acquires an electron from the...
02:50Catalysis
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
01:27Catalysis
Catalysis influences the rate of chemical reactions by providing an alternative reaction pathway with lower activation energy. A catalyst speeds up a reaction, but it is not consumed during the process. The fundamental principle of catalysis is the ability of a catalyst to alter the reaction mechanism, often introducing a more efficient pathway than the uncatalyzed process.In a catalyzed reaction, the catalyst participates directly in the reaction mechanism. It interacts with reactants to form...
02:44Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
01:30Anoxygenic Photosynthesis
Anoxygenic photosynthesis is a phototrophic process that captures light energy to drive carbon fixation without producing molecular oxygen. Unlike oxygenic photosynthesis, which utilizes water as an electron donor and releases oxygen, anoxygenic phototrophs use alternative electron donors such as hydrogen sulfide (H₂S), elemental sulfur (S⁰), or thiosulfate (S₂O₃²⁻). This process is carried out by diverse groups of bacteria, including purple bacteria, green sulfur bacteria, heliobacteria, and...