Enhancing the photocatalytic regeneration of nicotinamide cofactors with surface engineered plasmonic antenna-reactor system

Abstract

A rational design of photocatalytic materials is essential to efficiently extract the photogenerated charge carriers, en route to achieving the desired chemical transformations. Here, we have incorporated the concept of ‘favorable catalyst-reactant interaction’ into the ‘antenna-reactor system’ to enhance the efficiency of charge carrier extraction in plasmonic photocatalysis. The benefits of coupling these two emerging strategies are utilized for the efficient visible-light photocatalyzed regeneration of nicotinamide cofactors. The photocatalytic antenna-reactor system comprises gold-rhodium nanoflowers (Au@Rh NFs), which are functionalized with negatively charged surface ligands to bring the favorable electrostatic interactions into action. The dual role of rhodium nanoparticles (RhNPs) – as an electron acceptor and as a reactor site – ensures an efficient extraction of the hot charge carriers from the plasmonic AuNP to the RhNP, and further to the reactants. Likewise, the introduction of favorable electrostatic interaction helps in channeling the electron mediators close to the catalyst surface, thereby enhancing the probability of the charge transfer process. Both these factors play a crucial role in the enhanced photocatalytic regeneration of nicotinamide cofactors by the Au@Rh NFs based antenna-reactor system. The photocatalytic activity of Au@Rh NFs based antenna-reactor system is well-retained for multiple cycles, proving their suitability for applied studies as well. Thus, our work showcases the power of coupling different concepts in plasmonic photocatalysis for enhancing the charge extraction process, which can be easily extended to different classes of solar to chemical fuel conversions.