Ni Cluster‐Decorated Single‐Atom Catalysts Achieve Near‐Unity CO <sub>2</sub> ‐to‐CO Conversion with an Ultrawide Potential Window of ≈1.7 V
Yaqian Li, Yaqian Li, Xi Cao, Qingqing Chen, Rongrong Pan, Jian Zhang, Ge Meng, Yun Yang, Yapeng Li, Yapeng Li, Junjie Mao, Wei Chen
Abstract
Abstract Developing efficient electrocatalysts for CO 2 reduction to CO within a broad potential range is meaningful for cascade application integration. In this work, hydrogen spillover is created and utilized to cultivate a proton‐rich environment via the simple thermolysis of a Ni‐doped Zn coordination polymer (Zn CPs (Ni)) to create asymmetric Ni single atoms co‐located with adjacent Ni nanoclusters on nitrogen‐doped carbon, termed as Ni NC&SA /N‐C, which expedites the hydrogenation of adsorbed CO 2 . Therefore, the sample demonstrates near‐unity CO 2 ‐to‐CO conversion efficiency under pH‐universal conditions in ultra‐wide potential windows: −0.39 to −2.05 V versus RHE with the current densities ranging from 0.1 to 1.0 A cm −2 in alkaline conditions, −0.83 to −2.40 V versus RHE from 0.1 to 0.9 A cm −2 in neutral environments, and −0.98 to −2.25 V versus RHE across 0.1 to 0.8 A cm −2 in acid conditions. Corresponding in situ measurements and density functional theory (DFT) calculations suggest that the enhanced H 2 O dissociation and more efficient hydrogen spillover on Ni NC&SA /N‐C (compared to Ni SA /N‐C) accelerate the protonation of adsorbed CO 2 to form *COOH intermediates. This work emphasizes the significant role of proton spillover in CO 2 RR, opening novel avenues for designing high‐performance catalysts applicable to various electrocatalytic processes.