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

The production of high-demand syngas with tunable ratios by CO₂ electroreduction has attracted considerable research interest. However, it is challenging to balance the evolution performance of H₂ and CO with wide H₂/CO ratios, while maintaining high efficiency. Herein, nitrogen-coordinated hierarchical porous carbon spheres with varying phosphorus content (P_xNC-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 ^∗CO₂-to-^∗COOH and promoting moderate H^∗ adsorption. Specifically, syngas with wide H₂/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_1.0NC-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-CO₂ batteries. Our work provides valuable insights into the rational design of carbon-based catalysts for CO₂ reduction.