TY - JOUR
T1 - Mimicking Metalloenzyme Microenvironments in the Transition Metal-Single Atom Catalysts for Electrochemical Hydrogen Peroxide Synthesis in an Acidic Medium
AU - Muthusamy, Saravanakumar
AU - Sabhapathy, Palani
AU - Raghunath, Putikam
AU - Sabbah, Amr
AU - Chang, Yu Chung
AU - Krishnamoorthy, Vimal
AU - Ho, Thi Thong
AU - Chiou, Jau Wern
AU - Lin, Ming Chang
AU - Chen, Li Chyong
AU - Chen, Kuei Hsien
N1 - Publisher Copyright:
© 2023 Wiley-VCH GmbH.
PY - 2023
Y1 - 2023
N2 - Electrochemical reduction of oxygen into hydrogen peroxide in an acidic medium offers an energy-efficient and green H2O2 synthesis as an alternative to the energy-intensive anthraquinone process. Unfortunately, high overpotential, low production rates, and fierce competition from traditional four-electron reduction limit it. In this study, a metalloenzyme-like active structure is mimicked in carbon-based single-atom electrocatalysts for oxygen reduction to H2O2. Using a carbonization strategy, the primary electronic structure of the metal center with nitrogen and oxygen coordination is modulated, followed by epoxy oxygen functionalities close to the metal active sites. In an acidic medium, CoNOC active structures proceed with greater than 98% H2O2 selectivity (2e−/2H+) rather than CoNC active sites that are selective to H2O (4e−/4H+). Among all MNOC (M = Fe, Co, Mn, and Ni) single-atom electrocatalysts, the CoNOC is the most selective (> 98%) for H2O2 production, with a mass activity of 10 A g−1 at 0.60 V vs. RHE. X-ray absorption spectroscopy is used to identify the formation of unsymmetrical MNOC active structures. Experimental results are also compared to density functional theory calculations, which revealed that the structure-activity relationship of the epoxy-surrounded CoNOC active structure reaches optimum (ΔG*OOH) binding energies for high selectivity.
AB - Electrochemical reduction of oxygen into hydrogen peroxide in an acidic medium offers an energy-efficient and green H2O2 synthesis as an alternative to the energy-intensive anthraquinone process. Unfortunately, high overpotential, low production rates, and fierce competition from traditional four-electron reduction limit it. In this study, a metalloenzyme-like active structure is mimicked in carbon-based single-atom electrocatalysts for oxygen reduction to H2O2. Using a carbonization strategy, the primary electronic structure of the metal center with nitrogen and oxygen coordination is modulated, followed by epoxy oxygen functionalities close to the metal active sites. In an acidic medium, CoNOC active structures proceed with greater than 98% H2O2 selectivity (2e−/2H+) rather than CoNC active sites that are selective to H2O (4e−/4H+). Among all MNOC (M = Fe, Co, Mn, and Ni) single-atom electrocatalysts, the CoNOC is the most selective (> 98%) for H2O2 production, with a mass activity of 10 A g−1 at 0.60 V vs. RHE. X-ray absorption spectroscopy is used to identify the formation of unsymmetrical MNOC active structures. Experimental results are also compared to density functional theory calculations, which revealed that the structure-activity relationship of the epoxy-surrounded CoNOC active structure reaches optimum (ΔG*OOH) binding energies for high selectivity.
KW - d-band center
KW - electrocatalysis
KW - electrochemical HO production
KW - electronic structures
KW - oxygen reduction reaction
KW - single-atom catalysts
UR - http://www.scopus.com/inward/record.url?scp=85163844561&partnerID=8YFLogxK
U2 - 10.1002/smtd.202300234
DO - 10.1002/smtd.202300234
M3 - Article
AN - SCOPUS:85163844561
SN - 2366-9608
JO - Small Methods
JF - Small Methods
ER -