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Title: Lepidocrocite TiO2 nanofilaments: optical properties revealed by ultrafast transient absorption
Use of nanomaterials for photocatalysis faces challenges such as complex synthesis, high cost, low scalability, and dependance on UV radiation for initiating the photocatalytic activity. We recently demonstrated scalable, one-pot syntheses of one-dimensional (1D) lepidocrocite-based nanofilaments (NFs), 1DL NFs, that have the potential to overcome some of the challenges. 1DL NFs are exceptionally stable in water, have a large surface to volume ratio, and sub-square-nanometer cross sections. Initial reports show the semiconducting nature of this material, with an indirect band gap energy of 4.0 eV, one of the highest ever reported for a titania material. In this work, we present a study of the electronic and optical properties of these newly discovered 1DL NFs using ultrafast transient optical absorption. We show that despite the large band gap of this material, sub-gap states can be accessed with visible light illumination only, and photoexcited species reveal decay times in the nanosecond scale. Long lived photoexcitations in the visible range, without assistance by UV illumination, pave the way for possible application in photocatalysis.  more » « less
Award ID(s):
2021871
PAR ID:
10523463
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Editor(s):
Betz, Markus; Elezzabi, Abdulhakem Y
Publisher / Repository:
SPIE
Date Published:
Volume:
1288409
ISBN:
9781510670280
Page Range / eLocation ID:
22
Format(s):
Medium: X
Location:
San Francisco, United States
Sponsoring Org:
National Science Foundation
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