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Title: Identifying Catalytic Active Sites of Trimolybdenum Phosphide (Mo 3 P) for Electrochemical Hydrogen Evolution
Abstract Solid‐state electrocatalysis plays a crucial role in the development of renewable energy to reshape current and future energy needs. However, finding an inexpensive and highly active catalyst to replace precious metals remains a big challenge for this technology. Here, tri‐molybdenum phosphide (Mo3P) is found as a promising nonprecious metal and earth‐abundant candidate with outstanding catalytic properties that can be used for electrocatalytic processes. The catalytic performance of Mo3P nanoparticles is tested in the hydrogen evolution reaction (HER). The results indicate an onset potential of as low as 21 mV, H2formation rate, and exchange current density of 214.7 µmol s−1g−1cat(at only 100 mV overpotential) and 279.07 µA cm−2, respectively, which are among the closest values yet observed to platinum. Combined atomic‐scale characterizations and computational studies confirm that high density of molybdenum (Mo) active sites at the surface with superior intrinsic electronic properties are mainly responsible for the remarkable HER performance. The density functional theory calculation results also confirm that the exceptional performance of Mo3P is due to neutral Gibbs free energy (ΔGH*) of the hydrogen (H) adsorption at above 1/2 monolayer (ML) coverage of the (110) surface, exceeding the performance of existing non‐noble metal catalysts for HER.  more » « less
Award ID(s):
1809439
PAR ID:
10461091
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Energy Materials
Volume:
9
Issue:
22
ISSN:
1614-6832
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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