Charge carrier dynamics and photocatalytic activity of {111} and {100} faceted Ag3PO4 particles

Abstract

Silver orthophosphate (Ag 3 PO 4 ) is a highly promising visible light photocatalyst with high quantum yield for solar driven water oxidation. Recently, the performance of this material has been further enhanced using facet-controlled synthesis. The tetrahedral particles with {111} exposed facets demonstrate higher photocatalytic performance than the cubic particles with {100} exposed facets. However, the reason behind this large difference in photocatalytic performance is still not understood. In this work, we study the free charge carrier dynamics, such as mobility, lifetime, and diffusion lengths, for the {111}-faceted tetrahedral and the {100}-faceted cubic particles using time-resolved microwave conductivity (TRMC) measurements. An order of magnitude higher charge carrier mobility and diffusion length is found for the tetrahedral particles as compared to the cubic particles. The differences in crystal structure, surface composition, and optical properties are investigated in order to understand how these properties impact the charge carrier dynamics and the photocatalytic performance of the differently faceted particles.

Introducing special issue on photocatalysis and photoelectrochemistry

“…To better understand the role played by co-catalysts, Ketwong et al 21 report on the possible complex functionalities. How and where co-catalysts interface with the photoactive material is also important, as shown by Adler et al, 22 The Journal of Chemical Physics EDITORIAL scitation.org/journal/jcp Sinha et al, 23 Wang et al, 24 Chen et al, 25 Yang et al, 26 and Li et al 27 More broadly, from a design perspective, the lightharvesting and catalytic components are not limited to solid-state materials. Indeed, molecular photosensitizers have been broadly studied for solar cell applications.…”