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Updated: Dec 24, 2025
06:32
A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions
Published on: August 17, 2016
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Unexpected Correlation Between Boron Chain Condensation and Hydrogen Evolution Reaction (HER) Activity in Highly
Eunsoo Lee1,2, Hyounmyung Park1,2, Hyunkeun Joo1
1Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, CA, 92521, USA.
Angewandte Chemie (International Ed. in English)
|April 10, 2020
Summary
Vanadium borides exhibit high electrocatalytic activity for hydrogen evolution. Their activity correlates with boron chain condensation, enabling prediction of performance for known and novel materials.
Area of Science:
- Materials Science
- Electrochemistry
- Catalysis
Background:
- Transition-metal borides (TMBs) are emerging as efficient electrocatalysts for the hydrogen evolution reaction (HER).
- Understanding the structure-activity relationship is crucial for designing advanced electrocatalytic materials.
Purpose of the Study:
- To investigate the HER electrocatalytic activity of vanadium borides (VB and V3B4).
- To establish a correlation between the crystal structure, specifically boron chain condensation, and HER activity in vanadium borides.
- To develop a predictive model for HER overpotentials in vanadium-boron systems.
Main Methods:
- Electrochemical characterization of VB and V3B4 for HER in sulfuric acid.
- Analysis of structure-activity relationships based on boron chain condensation.
- Development of an exponential equation to predict overpotentials for various VxB_y phases.
Main Results:
- VB and V3B4 demonstrate high electrocatalytic HER activity.
- HER activity increases with enhanced boron chain condensation in vanadium borides.
- Accurate prediction of overpotentials for VB2, V2B3, and hypothetical "V5B8" was achieved.
- An exponential equation was derived to predict overpotentials for VxB_y phases with boron chains.
Conclusions:
- A direct correlation between crystal structure and HER activity in vanadium borides was established.
- The findings facilitate the rational design of novel, high-performance electrocatalysts for HER.
- Structure-activity relationships offer a pathway to optimize electrocatalytic materials.
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