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Title: Effect of glycine functionalization of 2D titanium carbide (MXene) on charge storage
Restacking of two-dimensional (2D) flakes reduces the accessibility of electrolyte ions and is a problem in energy storage and other applications. Organic molecules can be used to prevent restacking and keep the interlayer space open. Here, we report on a combined theoretical and experimental investigation of the interaction between 2D titanium carbide (MXene), Ti 3 C 2 T x , and glycine. From first principle calculations, we presented the functionalization of glycine on the Ti 3 C 2 O 2 surface, evidenced by the shared electrons between Ti and N atoms. To experimentally validate our predictions, we synthesized flexible freestanding films of Ti 3 C 2 T x /glycine hybrids. X-ray diffraction and X-ray photoelectron spectroscopy confirmed the increased interlayer spacing and possible Ti–N bonding, respectively, which agree with our theoretical predictions. The Ti 3 C 2 T x /glycine hybrid films exhibited an improved rate and cycling performances compared to pristine Ti 3 C 2 T x , possibly due to better charge percolation within expanded Ti 3 C 2 T x .  more » « less
Award ID(s):
1740795
PAR ID:
10059194
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
6
Issue:
11
ISSN:
2050-7488
Page Range / eLocation ID:
4617 to 4622
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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