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Title: Topotactic BI 3 -assisted borodization: synthesis and electrocatalysis applications of transition metal borides
A facile and universal route for synthesizing transition metal borides has been developed by reaction of boron triiodide (BI 3 ) with elemental transition metals. This method employs relatively low synthesis temperatures to afford single-phase samples of various binary and ternary metal borides, such as Fe 2 B, Co 2 B, Ni 3 B, TiB 2 , VB 2 , CrB 2 , and Ni 2 CoB. This synthesis protocol can be utilized for the topotactic transformation of metal shapes into their respective borides, as exemplified by transformation of Ni foam to Ni 3 B foam. In situ powder X-ray diffraction studies of the Ni–BI 3 system showed that the crystalline nickel borides, Ni 4 B 3 and Ni 2 B, start to form at temperatures as low as 700 K and 877 K, respectively, which is significantly lower than the typical synthesis temperatures required to produce these borides. Ni 3 B synthesized by this method was tested as a supporting material for oxygen evolution reaction (OER) in acidic media. Composite electrocatalysts of IrO 2 /Ni 3 B with only 50% of IrO 2 exhibit current densities and stability similar to pure IrO 2 at mass loadings lower than 0.5 mg cm −2 , indicating Ni 3 B could be a promising supporting material for acidic OER.  more » « less
Award ID(s):
1955456
NSF-PAR ID:
10442749
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
10
Issue:
40
ISSN:
2050-7488
Page Range / eLocation ID:
21738 to 21749
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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