Can N, S Cocoordination Promote Single Atom Catalyst Performance in CO<sub>2</sub>RR? Fe‐N<sub>2</sub>S<sub>2</sub> Porphyrin versus Fe‐N<sub>4</sub> Porphyrin
Shoufu Cao, Shuxian Wei, Xiaofei Wei, Sainan Zhou, Hongyu Chen, Yuying Hu, Zhaojie Wang, Siyuan Liu, Wenyue Guo, Xiaoqing Lü
Abstract
Abstract Single atom catalysts (SACs) are promising electrocatalysts for CO 2 reduction reaction (CO 2 RR), in which the coordination environment plays a crucial role in intrinsic catalytic activity. Taking the regular Fe porphyrin (Fe‐N 4 porphyrin) as a probe, the study reveals that the introduction of opposable S atoms into N coordination (Fe‐N 2 S 2 porphyrin) allows for an appropriate electronic structural optimization on active sites. Owing to the additional orbitals around the Fermi level and the abundant Fe orbital occupation after S substitution, N, S cocoordination can effectively tune SACs and thus facilitating protonation of intermediates during CO 2 RR. CO 2 RR mechanisms lead to possible C1 products via two‐, six‐, and eight‐electron pathways are systematically elucidated on Fe‐N 4 porphyrin and Fe‐N 2 S 2 porphyrin. Fe‐N 4 porphyrin yields the most favorable product of HCOOH with a limiting potential of −0.70 V. Fe‐N 2 S 2 porphyrin exhibits low limiting potentials of −0.38 and −0.40 V for HCOOH and CH 3 OH, respectively, surpassing those of most Cu‐based catalysts and SACs. Hence, the N, S cocoordination might provide better catalytic environment than regular N coordination for SACs in CO 2 RR. This work demonstrates Fe‐N 2 S 2 porphyrin as a high‐performance CO 2 RR catalyst, and highlights N, S cocoordination regulation as an effective approach to fine tune high atomically dispersed electrocatalysts.