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Title: Enhanced charge separation in TiO 2 /nanocarbon hybrid photocatalysts through coupling with short carbon nanotubes
The interfacial contact between TiO 2 and graphitic carbon in a hybrid composite plays a critical role in electron transfer behavior, and in turn, its photocatalytic efficiency. Herein, we report a new approach for improving the interfacial contact and delaying charge carrier recombination in the hybrid by wrapping short single-wall carbon nanotubes (SWCNTs) on TiO 2 particles (100 nm) via a hydration-condensation technique. Short SWCNTs with an average length of 125 ± 90 nm were obtained from an ultrasonication-assisted cutting process of pristine SWCNTs (1–3 μm in length). In comparison to conventional TiO 2 –SWCNT composites synthesized from long SWCNTs (1.2 ± 0.7 μm), TiO 2 wrapped with short SWCNTs showed longer lifetimes of photogenerated electrons and holes, as well as a superior photocatalytic activity in the gas-phase degradation of acetaldehyde. In addition, upon comparison with a TiO 2 –nanographene “quasi-core–shell” structure, TiO 2 -short SWCNT structures offer better electron-capturing efficiency and slightly higher photocatalytic performance, revealing the impact of the dimensions of graphitic structures on the interfacial transfer of electrons and light penetration to TiO 2 . The engineering of the TiO 2 –SWCNT structure is expected to benefit photocatalytic degradation of other volatile organic compounds, and provide alternative pathways to further improve the efficiency of other carbon-based photocatalysts.  more » « less
Award ID(s):
1653527
PAR ID:
10315102
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
RSC Advances
Volume:
11
Issue:
19
ISSN:
2046-2069
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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