Efficient Electrochemical Hydrogen Peroxide Production from Molecular Oxygen on Nitrogen-Doped Mesoporous Carbon Catalysts

Abstract

Electrochemical hydrogen peroxide (H 2 O 2 ) production by two-electron oxygen reduction is a promising alternative process to the established industrial anthraquinone process. Current challenges relate to finding cost-effective electrocatalysts with high electrocatalytic activity, stability, and product selectivity. Here, we explore the electrocatalytic activity and selectivity toward H 2 O 2 production of a number of distinct nitrogen-doped mesoporous carbon catalysts and report a previously unachieved H 2 O 2 selectivity of ∼95−98% in acidic solution. To explain our observations, we correlate their structural, compositional, and other physicochemical properties with their electrocatalytic performance and uncover a close correlation between the H 2 O 2 product yield and the surface area and interfacial zeta potential. Nitrogen doping was found to sharply boost H 2 O 2 activity and selectivity. Chronoamperometric H 2 O 2 electrolysis confirms the exceptionally high H 2 O 2 production rate and large H 2 O 2 faradaic selectivity for the optimal nitrogen-doped CMK-3 sample in acidic, neutral, and alkaline solutions. In alkaline solution, the catalytic H 2 O 2 yield increases further, where the production rate of the HO 2 − anion reaches a value as high as 561.7 mmol g catalyst −1 h −1 with H 2 O 2 faradaic selectivity above 70%. Our work provides a guide for the design, synthesis, and mechanistic investigation of advanced carbon-based electrocatalysts for H 2 O 2 production.

Selective Electrocatalytic H2O2 Generation by Cobalt@N‐Doped Graphitic Carbon Core–Shell Nanohybrids

“…Hence, the increased mesoporosity and the largerp ores are correlated with an increased selectivity towards H 2 O 2 under the appliedc onditions. These findings are in agreement with past [17] and recent reports, [18] which correlate extensive mesoporosityo ft he carbon catalystw ith high H 2 O 2 selectivity.T he high surface area is also correlated with high activity as previously demonstrated. [19] Electrochemical impedance spectroscopy (EIS) characterization of the ORR process in at hree-electrode configuration was performed with an optimized Nafion-containing (5 mL) thin-film catalysta nd is discussed in the SupportingI nformation.…”

“…Hence, the increased mesoporosity and the larger pores are correlated with an increased selectivity towards H 2 O 2 under the applied conditions. These findings are in agreement with past and recent reports, which correlate extensive mesoporosity of the carbon catalyst with high H 2 O 2 selectivity. The high surface area is also correlated with high activity as previously demonstrated …”

Tailoring the Electrochemical Production of H2O2: Strategies for the Rational Design of High‐Performance Electrocatalysts

“…Numerous studies have elucidated the importance of surface charges and surface defects in determining the performance of carbon‐based catalysts. Furthermore, the porosity (pore size and pore density) of the carbon material is also observed to largely influence the mass transport while providing additional active sites toward H 2 O 2 production …”

“…Sun et al observed that carbon catalysts exhibiting a high selectivity for H 2 O 2 possessed a positive zeta potential, an indication of the amount of surface charges. This observation may have two possible explanations.…”

Recent Advanced Materials for Electrochemical and Photoelectrochemical Synthesis of Ammonia from Dinitrogen: One Step Closer to a Sustainable Energy Future

“…) could be a viable solution. Using renewable electricity as the energy source, electrochemical and photoelectrochemical conversion schemes can perform chemical reactions under ambient conditions (room temperature and atmospheric pressure) and have been utilized to synthesize many valuable chemicals including hydrogen, hydrogen peroxide, hydrocarbons, and oxygenates . In an ideal scenario, as a good source of hydrogen, NH 3 can combine with oxygen (O 2 ) in the fuel cell system to generate electricity and N 2 ; while in the other half of the cycle, N 2 can be electrochemically transformed into NH 3 when coupled with a renewable electricity source, establishing a nitrogen‐neutral cycle for renewable energy utilization and regeneration as presented in Figure 1 .…”