Single Nickel Atom-Modified Phosphorene Nanosheets for Electrocatalytic CO₂ Reduction

Abstract

Nowadays, carbon dioxide (CO2) produced by global energy consumption far exceeds what the environment can absorb. So, the world is seeking a way to control and reduce CO2 emissions. The electrocatalytic CO2 reduction reaction (CRR) can effectively convert this greenhouse gas into energy sources, thus providing a method to solve CO2 emission and energy crisis issues. However, only quite limited catalysts are capable of converting CO2 into high-value C1 products. Herein, four structures of single Ni atom-modified phosphorene, as an electrocatalyst for the CRR, have been studied by first-principles calculations based on density functional theory (DFT). The results show that a single Ni atom adsorbed on monoatomic defective phosphorene (Ni-D-BP) has higher long-term activity and stability, and better CRR selectivity against the hydrogen evolution reaction (HER). In particular, Ni-D-BP shows good selectivity for HCOOH with a limiting potential of −0.31 V. The production of CH3OH and CH4 has the same limiting potential of −0.98 V, indicating that Ni-D-BP also has good catalytic properties for CH3OH or CH4 production. This study can reveal the mechanism of the CRR for single Ni atom-modified phosphorene-based catalysts and provide a way to design electrocatalysts for the CRR on the atomic scale.