Ultrathin single-crystal PtSe nanosheets for high-efficiency O electroreduction to HO.

Electrochemical synthesis of HO a two-electron oxygen reduction reaction (2e ORR) has emerged as a promising alternative to the anthraquinone process. However, the strong competition from the 4e pathway severely limits its activity and selectivity, especially for Pt-based catalysts. Herein, ultrathin single-crystal PtSe nanosheets were successfully prepared an selenization process using commercial Pt/C as a precursor, demonstrating an exclusive 2e ORR pathway compared to the 4e pathway of commercial Pt/C, delivering a high HO selectivity over a wide pH range (>80%, up to 94.1%). Furthermore, infrared spectroscopy results revealed Pt as an active center, accompanied by the key intermediate OOH* adsorption and HOOH formation.