Metal-free boron catalyst with oriented crystal phase interfacial interaction for efficient electrochemical production of hydrogen peroxide

Abstract

The in-depth research on the interfacial interaction of crystal phases in metal-free catalysts during the 4 e− oxygen reduction reaction (ORR) are scarce. Herein, the modified amorphous boron (A-boron) with high electrochemical performance was fabricated with a simple high-temperature annealing process. The self-regulation of the crystal phases interface in modified A-boron (A-B-600N2) was realized through the designed synthesis process, which result in the formation of strong electronic interaction between the amorphous phase and crystalline phase. The increased oxygen adsorption and reduced internal resistance contribute to the improvement of electrochemical activity. In an alkaline solution, the A-B-600N2 exhibited as high as 85 mmol·gcatalyst−1·h−1 H2O2 production rate and 65% Faradaic efficiency (FE) value. Besides, A-B-600N2 also presented excellent activity for degrading a series of organic pollutants in the electro-Fenton (EF) system. This discovery provides a new idea for the modification of a boron-based electrocatalyst that is practicable for a high H2O2 production rate in the alkaline medium and excellent pollutant degradation efficiency in the EF system.