Highly dispersed Ag clusters for active and stable hydrogen peroxide production
Mengmeng Jin, Wei Liu, Jiaqiang Sun, Xinzhong Wang, Shusheng Zhang, Jun Luo, Xijun Liu
Abstract
The electrosynthesis of hydrogen peroxide (H2O2) from oxygen reduction reaction (ORR) via a two-electron pathway provides an appealing alternative to the energy-intensive anthraquinone route; however, the development of ORR with high selectivity and durability for H2O2 production is still challenging. Herein, we demonstrate an active and stable catalyst, composing of highly dispersed Ag nanoclusters on N-doped hollow carbon spheres (NC-Ag/NHCS), which can effectively reduce O2 molecules into H2O2 with a selectivity of 89%–91% in a potential range from 0.2 to 0.7 V (vs. reversible hydrogen electrode (RHE)) in acidic media. Strikingly, NC-Ag/NHCS achieve a mass activity of 27.1 A·g−1 and a yield rate of 408 mmol·gcat.−1·h−1 at 0.7 V, both of which are comparable with the best-reported results. Furthermore, NC-Ag/NHCS enable catalyzing H2O2 production with a stable current density over 48-h electrolysis and only about 9.8% loss in selectivity after 10,000 cycles. Theoretical analyses indicate that Ag nanoclusters can contribute more electrons to favor the protonation of adsorbed O2, thus leading to a high H2O2 selectivity. This work confirms the great potential of metal nanocluster-based materials for H2O2 electrosynthesis under ambient conditions.