Two Birds with One Stone: Contemporaneously Enhancing OER Catalytic Activity and Stability for Dual-Phase
Fengqi Li1, Hao Wu1, Shaochen Lv2
1National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, P. R. China.
Small (Weinheim an Der Bergstrasse, Germany)
|October 27, 2023
Summary
A novel dual-phase medium-entropy metal sulfide, (FeCoNiMn₂)S₂, was synthesized to enhance oxygen evolution reaction (OER) electrocatalyst stability. This new material shows superior performance in Zn-air batteries, offering potential for energy conversion applications.
Area of Science:
- Materials Science
- Electrochemistry
- Catalysis
Background:
- Transition metal sulfides are promising electrocatalysts for the oxygen evolution reaction (OER).
- Current transition metal sulfide catalysts lack the stability required for large-scale commercial applications.
Purpose of the Study:
- To fabricate and characterize a novel dual-phase medium-entropy metal sulfide (dp-MEMS) for improved OER stability.
- To evaluate the catalytic activity and performance of the new material in rechargeable Zn-air batteries.
Main Methods:
- Synthesis of (FeCoNiMn₂)S₂ dp-MEMS.
- Electrochemical testing for OER performance (overpotential, current densities).
- Density functional theory (DFT) calculations to understand the enhancement mechanism.
- Integration and testing in rechargeable Zn-air batteries.
Main Results:
- The synthesized (FeCoNiMn₂)S₂ dp-MEMS exhibited enhanced stability for OER.
- Achieved low overpotentials of 169 mV at 10 mA cm⁻² and 232 mV at 100 mA cm⁻².
- Demonstrated superior performance in rechargeable Zn-air batteries compared to commercial catalysts (Pt/C+RuO₂).
Conclusions:
- Dual-phase medium-entropy metal sulfides offer a promising pathway for developing highly stable and efficient OER electrocatalysts.
- The "cell wall"-like structure and synergistic effects in the medium-entropy system contribute to enhanced catalytic activity and stability.
- (FeCoNiMn₂)S₂ dp-MEMS holds significant potential for OER and related energy conversion systems.
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