รายละเอียดเอกสาร

A hydrogen peroxide electrolyzer (HPEL) is the workhorse for an energy storage system based on the H2O2 electrochemical cycle. The high H2O2 utilization towards power-to-hydrogen conversion in the HPEL is essential to ensure the efficiency and cyclability of the system. Unfortunately, the H2O2 disproportionation at the anode and its crossover to the cathode in a proton exchange membrane (PEM) HPEL is detrimental to H2O2 utilization and must be mitigated. This work investigates the effects of the catalyst type, anode catalyst loading, and PEM thickness on H2O2 utilization in a PEM HPEL. The results show that the Co–N–C catalyst exhibits higher H2O2 utilization than the Fe–N–C and Pt/C catalysts due to its higher selectivity towards the hydrogen peroxide oxidation reaction (HPOR) and the lesser H2O2 disproportionation reaction (HPDR). Increasing the Co–N–C catalyst loading and PEM thickness can effectively inhibit the H2O2 crossover and improve the H2O2 utilization. On the other hand, the portion of the HPDR and the ohmic loss increase with the catalyst loading and PEM thickness, respectively. A maximum H2O2 utilization of over 98% can be achieved by balancing these factors. These results provide valuable guides to the catalyst design and device optimization for efficient energy storage systems based on the electrochemical H2O2–H2 cycle.