Constructing Interfacial Boron-Nitrogen Moieties in Turbostratic Carbon for Electrochemical Hydrogen Peroxide Production

The electrochemical oxygen reduction reaction (ORR) provides a green route for decentralized H2O2 synthesis, where a structure-selectivity relationship is pivotal for the control of a highly selective and active two-electron pathway. Here, we report the fabrication of a boron and nitrogen co-doped turbostratic carbon catalyst with tunable B-N-C configurations (CNB-ZIL) by the assistance of a zwitterionic liquid (ZIL) for electrochemical hydrogen peroxide production. Combined spectroscopic analysis reveals a fine tailored B-N moiety in CNB-ZIL, where interfacial B-N species in a homogeneous distribution tend to segregate into hexagonal boron nitride domains at higher pyrolysis temperatures. Based on the experimental observations, a correlation between the interfacial B-N moieties and HO2- selectivity is established. The CNB-ZIL electrocatalysts with optimal interfacial B-N moieties exhibit a high HO2- selectivity with small overpotentials in alkaline media, giving a HO2- yield of approximate to 1787 mmol g(catalyst)(-1) h(-1) at -1.4 V in a flow-cell reactor.

Automated summary

A boron and nitrogen co-doped turbostratic carbon catalyst (CNB-ZIL) with tunable B-N-C configurations was successfully synthesized using a zwitterionic liquid as an assistant for electrochemical hydrogen peroxide production. The fine-tailored B-N moiety in CNB-ZIL allows for selective and active HO2- generation, achieving a small overpotential in alkaline media.