FeP nanoparticles anchored on N-doped carbon as ORR/OER bifunctional catalyst and its application in Zn-air batteries

As a class of electrocatalysts with high electrocatalytic activity and abundant catalytic sites, transition metal phosphides still have problems such as low corrosion resistance and poor stability. A rational combination of FeP with N-doped carbon is an effective method to solve this problem. In this study, the FeP nanoparticles anchored on N-doped porous carbon nanosheets are successfully developed by wet leaching of the synthesized precursors with different amounts of phytic acid and subsequent calcination at 900 degrees C. The synergistic interaction between FeP and N-doped carbon causes electronic structure modulation in FeP/C-N, as confirmed by the XPS and XAS results. The appearance of P-C and Fe-N bonds enhances the catalysts' structural stability and supplies more active sites. The FeP/C-N-P0.28 catalyst has an ORR half-wave potential of 0.902 eV and an OER overpotential of 337 mV at 10 mA cm(-2), exhibiting powerful OER/ORR bifunctional catalyst activity. The zinc-air battery assembled using FeP/C-N-P0.28 catalyst displays a high specific capacity of 767 mAh/gZn and good cycling stability. This study provides an effective idea to prepare bifunctional efficient and inexpensive electrocatalysts.