One minute from pristine carbon to an electrocatalyst for hydrogen peroxide production

Abstract

Electrochemical production of hydrogen peroxide (H₂O₂) via oxygen reduction is a two-electron electrochemical process that has promising applications in production. In practical applications, developing high-performance nonprecious metal or metal-free electrocatalysts with cheap and commercially available source materials is challenging. Here, we prepared a high-performance electrocatalyst from commercial mesoporous carbon, CMK3, via microwave treatment for H₂O₂ production. Only 1 minute was consumed for the conversion of pristine CMK3 to a high-performance electrocatalyst via a microwave treatment and liquid nitrogen freezing process. The catalyst exhibited higher selectivity (∼90%) and current efficiency (∼95%) than pristine CMK3 (∼50% and ∼55%) in alkaline solution. Higher productivity of H₂O₂ was obtained (2476 mmol g_catalyst h⁻¹ at 0.3 V vs. RHE) than for the catalysts reported before. We investigated the system containing the H₂O₂ produced in situ for formaldehyde-containing wastewater treatment, and it exhibited high performance for reducing formaldehyde. This process presented a simple, fast and readily scalable approach to change a low-performance carbon material into a high-performance electrocatalyst. This work will be helpful in developing a high-performance electrocatalyst for producing H₂O₂ and the practical industrial application of reducing O₂ to H₂O₂ by an electrochemical method. It will also help to develop other high-performance electrocatalysts.