The active site engineering of electrocatalysts, as one of the most economical and technological approaches, is a promising strategy to enhance the intrinsic activity and selectivity towards electrochemical CO₂ reduction reaction. Herein, an indium-based porphyrin framework (In-TCPP) with a well-defined structure, highly dispersed catalytic center, and good stability was constructed for efficient CO₂-to-formate conversion. In-TCPP could achieve a high Faraday efficiency for formate (90%) and a cathodic energy efficiency of 63.8% in flow cells. In situ attenuated total reflectance Fourier transform infrared spectroscopy and density functional theory calculation confirm that the crucial intermediate is *COOH species which contributes to the formation of formate. This work is expected to provide novel insights into the precise design of active sites for high-performance electrocatalysts towards electrochemical CO₂ reduction reaction.

Since the advent of graphene in 2004, two-dimensional (2D) materials had ignited the development of fascinating functional materials for almost 20 years. Currently, the main members of 2D materials family are graphene, transition metal dichalcogenides (TMDs, MoS₂, WS₂, and others), MXenes (Ti₃C₂, Ta₄C₃, and others), Xenes (B, Si, P, Ge, and Sn), organic materials (COF, covalent organic frameworks), etc. The unique sheet-like morphology (single- or few-atomic-layer thickness) endow 2D materials with unconventional physicochemical properties for promising applications in catalysis, energy storage/conversion, electronics, biomedicine, sensors, etc. Nevertheless, the exploration and preparation of novel two-dimensional materials with desired characteristics through highly controlled strategy remains one of the major challenges in this field. In a recent work from Nature Chemistry published on 10 February 2022, Liu et al. reported a new member, clusterphene, in the family of two-dimensional materials.