UNS:Novel Photocatalysts based on TiO2-Passivated III-V Compounds for CO2 Reduction

UNS：基于 TiO2 钝化 III-V 族化合物的新型光催化剂，用于 CO2 还原

• 批准号: 1512505
• 负责人: Stephen Cronin
• 金额: $ 33万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2020-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1512505&HistoricalAwards=false
• 关键词: UNS; Novel; Photocatalysts; based; TiO2

1512505(Cronin)The work will address photocatalytic reduction of carbon dioxide, which is an exciting reaction system with the ability to convert an abundant greenhouse gas to combustible hydrocarbon fuels using sunlight. The proposed study will enable increased efficiency in carbon dioxide photoreduction through fundamental understanding of the photocatalytic reaction mechanisms. Direct solar-to-electrical energy conversion has reached very high efficiencies and low enough costs to compete with combustion of fossil fuels. As such, large scale implementation of gigawatt solar power plants have now become a reality. The main problem that remains, however, is that currently there is no way of storing this large amount of electricity for use during the night, winter months, or cloudy days, when the sun is not shining. Photocatalysis provides a way to store the sun's energy in chemical bonds that can later be released in a carbon neutral cycle.Specifically, the proposal is aimed at developing a fundamental understanding of photocatalytic processes on novel photocatalysts based on TiO2-passivated III-V compound semiconductors. Here, photocorrosion of the III-V compound surfaces is prevented by the TiO2 passivation layer. In order to establish the extent of photochemical robustness, the study will evaluate the stability of these photocatalysts over weeks and months for a wide range of TiO2 thicknesses and deposition conditions. The study will also investigate the reaction intermediates obtained in non-aqueous (and partially-aqueous) ionic liquid electrolytes (e.g., [EMIM]BF4), which suppress the formation of hydrogen, reduce the energy of the reaction intermediates, and enable the application of higher overpotentials. To separate the effects of the semiconductor substrate from the photoexcited carriers in the metal nanoparticles, experiments will also be carried out utilizing metal nanoparticles on non-semiconducting substrates, such as monolayer graphene.The principal investigators will also continue and expand educational and outreach activities in the Los Angeles and southern California area, including workshops for high school teachers from disadvantaged schools with added participation by their students, and with the development of photocatalysis related lab kits and demo units that will be given to the teachers to take back to their classrooms.

1512505（克罗宁）这项工作将解决二氧化碳的光催化还原，这是一个令人兴奋的反应系统，能够利用阳光将大量温室气体转化为可燃的碳氢化合物燃料。拟议的研究将通过对光催化反应机制的基本理解来提高二氧化碳光还原的效率。太阳能直接转化为电能的效率非常高，成本也很低，足以与化石燃料的燃烧相竞争。因此，吉瓦太阳能发电厂的大规模实施现已成为现实。然而，仍然存在的主要问题是，目前还没有办法储存如此大量的电力，供夜间、冬季或阴天使用。光催化提供了一种将太阳能储存在化学键中的方法，这些化学键随后可以在碳中性循环中释放。具体而言，该提案旨在对基于TiO 2钝化的III-V族化合物半导体的新型光催化剂的光催化过程进行基本理解。在此，通过TiO 2钝化层防止III-V族化合物表面的光腐蚀。为了确定光化学鲁棒性的程度，该研究将评估这些光催化剂在各种TiO 2厚度和沉积条件下数周和数月的稳定性。该研究还将研究在非水（和部分水）离子液体电解质中获得的反应中间体（例如，[EMIM] BF 4），其抑制氢的形成，降低反应中间体的能量，并且使得能够应用更高的过电位。为了将半导体基底的影响与金属纳米颗粒中的光激发载流子分离开，还将利用金属纳米颗粒在非半导体基底（如单层石墨烯）上进行实验。主要研究人员还将继续并扩大在洛杉矶和加州南部地区的教育和推广活动，包括为处境不利学校的高中教师举办讲习班，并增加学生的参与，并开发了与电子学习相关的实验工具包和演示单元，这些工具包和演示单元将提供给教师带回教室。