Towards molecular understanding of local chemical environment effects in electro- and photocatalytic CO2 reduction

Substantial progress has recently been made in the general understanding of the interfacial CO2 reduction reaction (CO2RR) in electro- and photocatalysis, but the influence of the local chemical environment and its effects on the catalytic interface at the molecular level remains largely elusive. Here, we introduce a classification scheme to group different aspects influencing the interfacial CO2RR thermodynamics and kinetics. This categorization allows a systematic survey of the literature focusing on the local chemical environment encompassing surface effects (adsorbates, support), solution interactions (electrolyte constituents) and three-dimensional chemical surroundings (polymers, metal organic frameworks (MOFs), covalent organic frameworks (COFs)). The review concludes with an outlook discussing possible future concepts for next-generation electrocatalytic and photocatalytic CO2RR. The electro- and photo-catalytic reduction of carbon dioxide are important processes in the context of developing a sustainable carbon-neutral economy. In this Review Article, the authors discuss how the local chemical environment in the proximity of the catalytic active site can influence the reactivity and selectivity of the processes and detail different approaches to achieve their modulation.