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Back-Gated van der Waals Heterojunction Manipulates Local Charges toward Fine-Tuning Hydrogen Evolution
Jiazhao Huang1, Zechao Zhuang2, Yang Zhao1
1State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, P. R. China.
Angewandte Chemie (International Ed. in English)
|April 22, 2022
Summary
Applying an external electric field to cobalt phthalocyanine (CoPc)/MoS2 heterojunctions precisely controls charge transfer, significantly boosting hydrogen evolution reaction (HER) activity by enhancing Mo-H bonding.
Area of Science:
- Materials Science
- Electrochemistry
- Catalysis
Background:
- Understanding charge redistribution is crucial for interpreting electrocatalytic mechanisms.
- Quantitative relationships between local charges and electrochemical performance can revolutionize catalyst design.
Purpose of the Study:
- To investigate the effect of an external electric field on charge transfer in cobalt phthalocyanine (CoPc)/MoS2 heterojunctions.
- To establish a correlation between charge accumulation and hydrogen evolution reaction (HER) activity.
Main Methods:
- Utilizing an external electric field to manipulate intermolecular charge transfer in CoPc/MoS2 heterojunctions.
- Employing in situ photoluminescence spectra and gate-dependent electrochemical measurements.
- Analyzing charge migration to sulfur vacancies and its effect on Mo-H bonding.
Main Results:
- External electric field successfully tuned the band gap of MoS2 and CoPc, confirming band engineering.
- Injected electrons migrated from CoPc to MoS2, accumulating at sulfur vacancies and strengthening Mo-H bonds.
- A linear correlation was observed between charge accumulation and enhanced HER activity.
Conclusions:
- External electric field provides a novel strategy for precisely regulating catalyst electronic configurations.
- This method offers a new pathway for designing advanced catalysts with improved activity.
- Fine-tuning charge distribution is key to optimizing electrocatalytic performance.
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