Precise regulation of phosphorus in nitrogen-coordinated porous carbon spheres for tunable CO2 electroreduction to syngas

The production of high-demand syngas with tunable ratios by CO 2 electroreduction has attracted considerable research interest. However, it is challenging to balance the evolution performance of H 2 and CO with wide H 2 /CO ratios, while maintaining high efficiency. Herein, nitrogen-coordinated hierarchical porous carbon spheres with varying phosphorus content (P x NC-T) are assembled to regulate syngas production performance. The precise introduction of P modulates the local charge distribution of nitrogen-coordinated carbons, thereby accelerating the protonation process of ∗ CO 2 -to- ∗ COOH and promoting moderate H ∗ adsorption. Specifically, syngas with wide H 2 /CO ratios (0.60–4.98) is obtained over a low potential range (−0.46 to −0.86 V vs. RHE). As a representative, P 1.0 NC-900 presents a remarkable current density (−152 mA cm −2 ) at −1.0 V vs. RHE in flow cells and delivers a decent peak power density (1.93 mW cm −2 ) in reversible Zn-CO 2 batteries. Our work provides valuable insights into the rational design of carbon-based catalysts for CO 2 reduction.