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Title: Unexpected Correlation Between Boron Chain Condensation and Hydrogen Evolution Reaction (HER) Activity in Highly Active Vanadium Borides: Enabling Predictions
Abstract

Transition‐metal borides (TMBs) have recently attracted attention as excellent hydrogen evolution (HER) electrocatalysts in bulk crystalline materials. Herein, we show for the first time that VB and V3B4have high electrocatalytic HER activity. Furthermore, we show that the HER activity (in 0.5 mH2SO4) increases with increasing boron chain condensation in vanadium borides: Using a −23 mV overpotential decrement derived from −0.296 mV (for VB at −10 mA cm−2current density) and −0.273 mV (for V3B4) we accurately predict the overpotential of VB2(−0.204 mV) as well as that of unstudied V2B3(−0.250 mV) and hypothetical “V5B8” (−0.227 mV). We then derived an exponential equation that predicts the overpotentials of known and hypothetical VxByphases containing at least a boron chain. These results provide a direct correlation between crystal structure and HER activity, thus paving the way for the design of even better electrocatalytic materials through structure–activity relationships.

 
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NSF-PAR ID:
10149506
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
132
Issue:
29
ISSN:
0044-8249
Page Range / eLocation ID:
p. 11872-11876
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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