ZrP2O7/P-doped carbon: A pathway to enhanced 2e− ORR activity in seawater environments

Developing 2e− ORR catalysts that utilize seawater as an electrolyte is crucial for advancing energy storage technologies and controlling marine pollution. While non-metal-doped carbon materials demonstrate strong 2e− ORR performance in simulated seawater, enhancing their performance at high current densities and ensuring stability in actual seawater are major challenges. In this paper, a ZrP2O7/P-doped carbon (PC) composite catalyst was synthesized by a one-step sintering method, which exhibited a high FE% of 95.89 % in 0.5 M NaCl solution with an H2O2 yield of 3.52 mol g−1h−1, and also maintained an FE% of 83.79 % in real seawater. It was significantly better than PC (87.14 %, 3.20 mol g−1h−1 in 0.5 M NaCl, 68.15 %, 2.50 mol g−1h−1 in seawater). Experiments and theoretical calculations revealed the crucial role of ZrP2O7 in enhancing ORR performance. It facilitates proton transfer to the catalyst surface and impedes the accumulation of magnesium and calcium hydroxides on the electrode, enabling efficient H2O2 synthesis by the catalyst in real seawater under high current density.