Transformation-Optics-Designed Plasmonic Singularities for Efficient Photocatalytic Hydrogen Evolution at Metal/Semiconductor Interfaces
Tingting Lin, Tianyi Yang, Yuhang Cai, Jingwei Li, Guangxiang Lu, Shuangqun Chen, Yi Li, Liang Guo, Stefan A. Maier, Changxu Liu, Jianfeng Huang
Abstract
High Resolution Image Download MS PowerPoint Slide Inspired by transformation optics, we propose a new concept for plasmonic photocatalysis by creating a novel hybrid nanostructure with a plasmonic singularity. Our geometry enables broad and strong spectral light harvesting at the active site of a nearby semiconductor where the chemical reaction occurs. A proof-of-concept nanostructure comprising Cu 2 ZnSnS 4 (CZTS) and Au–Au dimer ( [email protected] –Au) is fabricated via a colloidal strategy combining templating and seeded growth. On the basis of numerical and experimental results of different related hybrid nanostructures, we show that both the sharpness of the singular feature and the relative position to the reactive site play a pivotal role in optimizing photocatalytic activity. Compared with bare CZTS, the hybrid nanostructure ( [email protected] –Au) exhibits an enhancement of the photocatalytic hydrogen evolution rate by up to ∼9 times. The insights gained from this work might be beneficial for designing efficient composite plasmonic photocatalysts for diverse photocatalytic reactions.