Spectroscopic identification of active sites of oxygen-doped carbon for selective oxygen reduction to hydrogen peroxide

DOI: 10.1002/anie.202303525

Authors: Longxiang Liu (University College London) , Liqun Kang (Max-Planck-Institute for Chemical Energy Conversion) , Arunabhiram Chutia (University of Lincoln) , Jianrui Feng (University College London) , Martyna Michalska (University College London (UCL)) , Pilar Ferrer (Diamond Light Source) , David Grinter (University College London, Diamond Light Source) , Georg Held (Diamond Light Source) , Yeshu Tan (University College London (UCL)) , Fangjia Zhao (University College London) , Fei Guo (University College London) , David Hopkinson (Diamond Light Source) , Christopher Allen (Diamond Light Source) , Yanbei Hou (Nanyang Technological University) , Junwen Gu (University College London (UCL)) , Ioannis Papakonstantinou (University College London) , Paul Shearing (University College London) , Dan Brett (University College London) , Ivan P. Parkin (University College London) , Guanjie He (University College London)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Angewandte Chemie International Edition

State: Published (Approved)
Published: March 2023
Diamond Proposal Number(s): 29340 , 32501 , 30614 , 29809 , 32058

Abstract: The electrochemical synthesis of hydrogen peroxide (H2O2) via a two-electron (2e-) oxygen reduction reaction (ORR) process provides a promising alternative to replace the energy-intensive anthraquinone process. However, the development of efficient electrocatalysts is still facing lots of challenges like insufficient understanding of active sites. Herein, we develop a facile template-protected strategy to synthesize a highly active quinone-rich porous carbon catalyst (PCC) for H2O2 electrochemical production. The optimized PCC900 exhibits unprecedented activity and selectivity, of which the onset potential reaches 0.83 V vs. reversible hydrogen electrode in 0.1 M KOH and the H2O2 selectivity is over 95 % in a wide potential range. Comprehensive synchrotron-based near-edge X-ray absorption fine structure (NEXAFS) spectroscopy combined with electrocatalytic characterizations reveals the positive correlation between quinone content and 2e- ORR performance. The effectiveness of chair-form quinone groups as the most efficient active sites is highlighted by the molecule-mimic strategy and theoretical analysis.

Journal Keywords: Electrocatalysis; Hydrogen Peroxide; Quinone; Porous Carbon; NEXAFS

Subject Areas: Chemistry, Materials

Diamond Offline Facilities: Electron Physical Sciences Imaging Centre (ePSIC)
Instruments: B07-B1-Versatile Soft X-ray beamline: High Throughput ES1 , E02-JEM ARM 300CF

Added On: 19/03/2023 16:26

Documents:
Angew Chem Int Ed - 2023 - Liu - Spectroscopic Identification of Active Sites of Oxygen‐Doped Carbon for Selective Oxygen.pdf

Discipline Tags:

Physical Chemistry Catalysis Chemistry Materials Science

Technical Tags:

Microscopy Spectroscopy Electron Microscopy (EM) Scanning Electron Microscopy (SEM) X-ray Absorption Spectroscopy (XAS) Near Edge X-ray Absorption Fine Structures (NEXAFS) Scanning Transmission Electron Microscopy (STEM)