Enhanced visible light photocatalytic hydrogen evolution of Ta2O5 nanohoneycomb induced by plasmonic Au nanoparticle array

Polystyrene nanospheres in the sizes of 400, 200, and 100 nm were employed as a template to form hexagonal close-packed Ta2O5 nanohoneycombs (nHCs) by means of solutionbased nanosphere lithography. Moreover, Au nanoparticle arrays with various diameters were further deposited on the Ta2O5 nHCs to achieve surface plasmon resonance (SPR) and enhance visible-light photocatalytic hydrogen evolution. Finite difference time domain (FDTD) simulation was performed and the result showed that the 100-nm Ta2O5 nHCs coupled with smaller Au nanoparticles exhibited more effective localized SPR effect to enclose the Ta2O5 photocatalyst. The photocatalytic hydrogen evolution results were consistent with those of FDTD simulation and photoelectrochemical tests. A concept of effective yield ratio is proposed to explain how the Au nanoparticle size and spacing affect the hydrogen evolution efficiency. & COPY; 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.