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Title: Diazonium functionalized fullerenes: a new class of efficient molecular catalysts for the hydrogen evolution reaction
Considerable efforts are being made to find cheaper and more efficient alternatives to the currently commercially available catalysts based on precious metals for the Hydrogen Evolution Reaction (HER). In this context, fullerenes have started to gain attention due to their suitable electronic properties and relatively easy functionalization. We found that the covalent functionalization of C 60 , C 70 and Sc 3 N@ I h C 80 with diazonium salts endows the fullerene cages with ultra-active charge polarization centers, which are located near the carbon-diazonium bond and improve the efficiency towards the molecular generation of hydrogen. To support our findings, Electrochemical Impedance Spectroscopy (EIS), double layer capacitance ( C dl ) and Mott–Schottky approximation were performed. Among all the functionalized fullerenes, DPySc 3 N@ I h C 80 exhibited a very low onset potential (−0.025 V vs. RHE) value, which is due to the influence of the inner cluster on the extra improvement of the electronic density states of the catalytic sites. For the first time, the covalent assembly of fullerenes and diazonium groups was used as an electron polarization strategy to build superior molecular HER catalytic systems.  more » « less
Award ID(s):
1827745
NSF-PAR ID:
10331303
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Nanoscale
Volume:
14
Issue:
10
ISSN:
2040-3364
Page Range / eLocation ID:
3858 to 3864
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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