Tailoring coordination environments of single-atom electrocatalysts for hydrogen evolution by topological heteroatom transfer
Sheng Qian, Feng Xu, Yu Fan, Ningyan Cheng, Huaiguo Xue, Ye Yuan, Romain Gautier, Tengfei Jiang, Jingqi Tian
Abstract
Abstract The rational design of carbon-supported transition-metal single-atom catalysts requires the precise arrangement of heteroatoms within the single-atom catalysts. However, achieving this design is challenging due to the collapse of the structure during the pyrolysis. Here, we introduce a topological heteroatom-transfer strategy to prevent the collapse and accurately control the P coordination in carbon-supported single-atom catalysts. As an illustration, we have prepared self-assembled helical fibers with encapsulated cavities. Within these cavities, adjustable functional groups can chelate metal ions (N x ···M n+ ···O y ), facilitating the preservation of the structure during the pyrolysis based phosphidation. This process allows for the transfer of heteroatoms from the assembly into single-atom catalysts, resulting in the precise coordination tailoring. Notably, the Co–P 2 N 2 –C catalyst exhibits electrocatalytic performance as a non-noble metal single-atom catalyst for alkaline hydrogen evolution, attaining a current density of 100 mA cm −2 with an overpotential of only 131 mV.