Efficient hydrogen peroxide generation using reduced graphene oxide-based oxygen reduction electrocatalysts

Abstract

Electrochemical oxygen reduction has garnered attention as an emerging alternative to the traditional anthraquinone oxidation process to enable the distributed production of hydrogen peroxide. Here, we demonstrate a selective and efficient nonprecious electrocatalyst, prepared through an easily scalable mild thermal reduction of graphene oxide, to form hydrogen peroxide from oxygen. During oxygen reduction, certain variants of the mildly reduced graphene oxide electrocatalyst exhibit highly selective and stable peroxide formation activity at low overpotentials (< 10 mV) under basic conditions, exceeding the performance of current state-of-the-art alkaline catalysts. Spectroscopic structural characterization and in situ Raman spectroelectrochemistry provide strong evidence that sp 2-hybridized carbon near-ring ether defects along sheet edges are the most active sites for peroxide production, providing new insight into the electrocatalytic design of carbon-based materials for effective peroxide production.

Electrochemically derived functionalized graphene for bulk production of hydrogen peroxide

“…can be oxidized via chemical treatment, and these oxidized forms of sp 2 -sp 3 carbon systems prefer peroxide formation in alkaline ORR process [25]. Such studies are supported by reports from other groups, where McCloskey et al showed that sp 2 -hybridized carbon near-ring ether defects along sheet edges are the most active sites for peroxide production in rGO [3]. They also showed that the performance of these rGO-based catalysts in alkaline conditions under low overpotential outperform the existing state-ofthe-art catalysts.…”

“…The high quantity of H 2 O 2 production in G-M1 can be attributed to its high degree of oxygen functional groups, particularly due to C=O. The amount of peroxide formed by this method is found to be higher or on par with recent reports [3]. This opens an efficient pathway for the single-step large-scale production of peroxidegenerating carbon-based ORR catalysts.…”

“…The concentration of the electrolyte was found to be related to the thickness of the formed exfoliated graphene and its functionalities, and the 1 M KF-based exfoliation resulted in ultrathin layers for the sample G-M1, which had a high amount of C=O groups but fewer C-F functionalities. These electrochemically exfoliated functionalized graphene samples are found to be highly stable in alkaline electrochemical conditions, whereby 3 h of ORR produced ≈34 mg/L of peroxide for an applied potential of 0.358 V vs RHE, indicating a production on par or higher than the recently reported stateof-the-art catalysts [3].…”

“…Hydrogen peroxide (H 2 O 2 ) is identified as one among the most important 100 chemicals in the world, and its applications extend from the pharmaceutical industry to water purification [1][2][3]. Today, a majority of the required H 2 O 2 is produced through the complex and energy-intensive anthraquinone method [4], and although it is popular, it has drawbacks such as side reactions, which consume the catalyst leading to the regeneration and hydrogenation of the catalyst [4].…”

2 D Hybrid of Ni‐LDH Chips on Carbon Nanosheets as Cathode of Zinc–Air Battery for Electrocatalytic Conversion of O2 into H2O2

“…To predict and screen the catalyst candidates, a volcano relationship using the *HOO (* indicates an adsorbed species) binding energy as descriptor was recently identified as a powerful tool . With this method, a variety of noble‐metal‐based alloyed materials have been identified as suitable electrocatalysts for suppressing the 4 e ORR process; nevertheless, there remains great potential to develop new precious‐metal‐free electrocatalysts for further improving the associated catalytic performance and lowering the cost.…”