Tuning of visible light-driven CO2 reduction and hydrogen evolution activity by using POSS-modified porous organometallic polymers

Abstract

Significant efforts have been devoted to the photochemical CO₂ reduction reaction (CO₂RR) as a significant pathway for the development of renewable energy systems. However, the competitive hydrogen evolution reaction (HER) greatly impedes the fundamental understanding and industrial application of the CO₂RR. Herein, we report polyhedral oligomeric silsesquioxane (POSS)-based porous organometallic polymers (POMPs) that are able to catalyze the photochemical CO₂RR to produce syngas. Their surface area, CO₂ adsorption ability, visible-light harvesting capacity and photoinduced electron–hole separation efficiency can be regulated by tuning the Re-bipyridine content in POMPs. Consequently, the effects of these properties on CO₂RR and HER activities have been investigated and the surface area and electron transfer efficiency of these materials have been elucidated as the key points. Importantly, we also reveal the applicability of the developed strategy in designing new catalysts for the CO₂RR.