Hot electron emission for Au nanoparticles sensitized TiO2 surface

报告摘要：Emission of photoexcited hot electrons from plasmonic metal nanostructures to semiconductors is key to a number of proposed nanophotonics technologies for solar harvesting, water splitting, photocatalysis, and a variety of optical sensing and photodetector applications. Favorable materials and catalytic properties make systems based on gold and TiO2 particularly interesting, but the internal photoemission efficiency for visible light is low because of the wide bandgap of the semiconductor. We investigated the incident photon-to-electron conversion efficiency of thin TiO2 films decorated with Au nanodisk antennas in an electrochemical circuit and found that incorporation of an Au mirror beneath the semiconductor amplified the photoresponse. The results highlight the intricate interplay between the near-field and farfield chiral response of a nanostructure and establishes a clear link to the emerging field of hot carrier plasmonics with numerous potential applications in photocatalysis and solar light harvesting.

报告人简介：方蔚瑞教授本科毕业于北京大学物理学院，博士毕业于中科院物理所，之后在瑞典查尔莫斯理工大学做博士后，目前在大连理工大学工作。方蔚瑞博士一直从事表面等离激元光子学的研究，研究兴趣及方向主要为等离激元波导，单分子表面增强拉曼光谱，针尖增强拉曼光谱，基于等离激元热电子的传感、催化及光能利用，等离激元手性材料研究。近年来，取得的成果主要包括：搭建了高真空针尖增强拉曼散射系统并利用此系统发现了拉曼测量中梯度场效应导致的非线性效应；系统地研究了表面等离激元波导的性质并基于此实现了远程拉曼窥镜、光子路由，提出了新型光子芯片的具体实现方案；系统地研究了不同对称性结构下等离激元纳米手性材料的性质、超手性场及应用、提出了等离激元手性的量化解释模型；系统研究了表面等离激元热电子的发射性质并实现了热电子水分解、光探测和催化等。近年来在高水平国际期刊上共发表SCI论文40多篇，包括Nano Letters，Light: Science & Applications，Nanoscale，ACS photonics，Langmuir，PRX等。文章总引用1151次(ResearcherID:A-9474-2009)，H因子17，4篇论文入选ESI高被引论文。