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Updated: Jul 8, 2026
10:57
Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
Symmetric-Waveform Alternating-Current Excitation Enables Full Ni Valence-State Transformation in Co-Ni Catalysts
Jinhui Hao1, Xiao Yang1, Qianwen Qiu1
1School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China.
Langmuir : the ACS Journal of Surfaces and Colloids
|July 6, 2026
Summary
A novel alternating-current activation strategy enhances oxygen evolution reaction (OER) catalysts by fully oxidizing nickel to Ni3+. This dynamic surface reconstruction boosts catalytic activity for sustainable hydrogen production.
Area of Science:
- Electrochemistry
- Materials Science
- Catalysis
Background:
- The oxygen evolution reaction (OER) is crucial for sustainable hydrogen production but is often limited by inefficient oxidation of transition metal catalysts.
- Conventional methods yield mixed-valence surfaces, hindering the full utilization of catalyst intrinsic activity.
Purpose of the Study:
- To develop a new activation strategy for high-performance, noble-metal-free OER catalysts.
- To engineer dynamic surface reconstruction for enhanced transition metal oxidation states.
Main Methods:
- Symmetric-waveform alternating-current (AC) activation strategy.
- Experimental characterization (e.g., XPS, XRD) and density functional theory (DFT) calculations.
- Electrochemical performance testing.
Main Results:
- AC activation induced full conversion of Ni2+ to Ni3+ and partial oxidation of Co2+ to Co3+.
- DFT revealed a shift in the rate-determining step and reduced activation barriers on Ni3+ surfaces.
- Enhanced Ni d-band center alignment and improved charge conductivity were observed.
- Catalytic activity increased by 12.5% with a 63.6 mV lower overpotential at 10 mA cm-2.
Conclusions:
- Dynamic valence-state engineering via AC activation is effective for designing advanced OER catalysts.
- This approach offers a pathway to high-performance, cost-effective catalysts for sustainable hydrogen production.
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