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Updated: Jun 1, 2026
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Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
Engineering Proton-Deficient Micro-Environments on Co-cluster/atom Ensembles for Efficient Cyclooctasulfur
1College of Chemistry and Chemical Engineering, Central South University, Changsha, P. R. China.
Small (Weinheim an Der Bergstrasse, Germany)
|May 30, 2026
Summary
This study introduces novel cobalt-cluster/atom ensembles (CoC/SA-NC) for efficient electrochemical synthesis of cyclooctasulfur (S8) from sulfur dioxide (SO2). The new catalyst significantly enhances S8 selectivity by suppressing the hydrogen evolution reaction (HER).
Area of Science:
- Electrochemistry
- Materials Science
- Environmental Chemistry
Background:
- Electrochemical synthesis of cyclooctasulfur (S8) from sulfur dioxide (SO2) offers a sustainable route for SO2 mitigation and sulfur recycling.
- The hydrogen evolution reaction (HER) competes with SO2 reduction, hindering S8 selectivity.
Purpose of the Study:
- To design and evaluate novel cobalt-cluster/atom ensembles (CoC/SA-NC) for highly selective electrocatalytic conversion of SO2 to S8.
- To investigate the mechanism by which CoC/SA-NC enhances S8 selectivity and suppresses HER.
Main Methods:
- Design and synthesis of Co-cluster/atom ensembles supported on nitrogen-doped carbon (CoC/SA-NC).
- Electrochemical characterization including cyclic voltammetry, linear sweep voltammetry, and chronoamperometry.
- Theoretical calculations (e.g., DFT) to predict adsorption energies and reaction pathways.
- Analysis of product selectivity and yield using techniques like gas chromatography and sulfur K-edge XANES.
Main Results:
- CoC/SA-NC demonstrated superior performance for SO2-to-S8 conversion, achieving a Faradaic efficiency of 87% and a yield of 2802.6 µmol mg-1 h-1.
- The catalyst exhibited enhanced SO2 adsorption and facilitated proton diffusion, promoting SO2 reduction reaction (SO2RR).
- A unique proton-deficient microenvironment was created, effectively suppressing the HER and improving catalyst stability with 80.5% potential retention after 7 cycles.
Conclusions:
- CoC/SA-NC is a highly effective catalyst for selective electrochemical S8 synthesis from SO2.
- The synergistic effect of Co atomic sites and clusters, along with tailored interfacial microenvironment, is crucial for high performance and stability.
- This work provides a new strategy for designing advanced electrocatalysts for sustainable sulfur recycling and pollution control.
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