Bioinspired Design of Heterogenous Single-Atomic-Site Catalysts for Electrocatalysis and Photocatalysis.

The emergence of single-atomic-site catalysts (SACs) provides a specific model to bridge the gap between homogeneous and heterogeneous catalysis. An interesting aspect in SACs is how to apply the bioinspired strategies in homogeneous biocatalysis to the design of heterogeneous SACs. The effectiveness of this approach relies on systematic insights in structural characteristics and catalytic mechanisms of both the biocatalysts and the heterogeneous SACs. This review will give a summary on the representative bioinspired single-atomic-site catalysts and their applications in heterogeneous electrocatalysis and photocatalysis. The fundamentals of bioinspired design strategies will be systematically discussed in the first shell coordination (quasi-homogeneous metal centers and coordination numbers/species) and the second/long-range coordination (heteroatoms doping, dual-metallic sites, nano-single-atom-site, and metal-support interaction). Also, the unique non-covalent interactions and oriented mass/proton/electron transfer channels in heterogenous SACs are highlighted as inspired by the outer microenvironment of biological systems. The practical electrocatalytic and photocatalytic applications of bioinspired SACs are further discussed by drawing inspiration from hydrogenase, nitrogenase, oxidase, and dehydrogenase to produce hydrogen-, carbon-, nitrogen-, and oxygen-based value-added chemicals. The current challenges and future opportunities for the development of bioinspired heterogenous SACs will also be discussed.