INVESTIGATIONS ON DYNAMIC PROMOTION OF HETEROGENEOUS PHOTOCATALYTIC REACTIONS

Abstract

Periodic illumination is an alternative strategy to promote heterogeneous photocatalysis by dynamically alternating between dark and illumination conditions. We identified that the research gaps in this research are literatures focusing primarily on oxidation reactions; the ongoing debates on the nature and promotion mechanisms of periodic illumination; and effects of illumination on adsorption steps were not considered for kinetic modelling under periodic illumination. Therefore, we expanded the reaction scopes and observed (1) quantum yield enhancement for H2 evolution from HCOOH; (2) activity enhancement for HCOOH-mediated nitrophenol hydrogenation; and (3) light intensity effects for alanine synthesis from lactic acid. We constructed a generic kinetic model by establishing scaling relationship between reactant adsorption energy and photogenerated electron concentration. Although the proposed model preliminarily captured the abovementioned outcomes in the form of regimes (depending on scaling parameter), the model limitations identified cannot be overlooked. Therefore, we provided thesis outlooks for both experimental and theoretical.