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Title: Role of Sn in the Amorphous-to-Crystalline Transition of TiO 2 Thin Films
The amorphous-to-crystalline transition in TiO2 films upon annealing in air yields different polymorphs, depending on the oxygen partial pressure during the deposition of the amorphous precursor film. We further manipulate the resulting polymorph by introducing Sn into the system. By depositing a few nanometer-thick layer of metallic Sn between two layers of amorphous TiO2 prepared to yield the anatase polymorph of TiO2, we find that it results in the rutile polymorph if the content of Sn is high enough. If Sn is introduced as an oxide, no rutile is formed; anatase is by far the predominant phase (with a very small amount of brookite). This observation is consistent with scavenging of oxygen by elemental Sn at the Sn/TiO2 interfaces, stabilizing the rutile structure that can accommodate oxygen vacancies.  more » « less
Award ID(s):
1945520
PAR ID:
10503948
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
ACS
Date Published:
Journal Name:
Crystal Growth & Design
Volume:
23
Issue:
12
ISSN:
1528-7483
Page Range / eLocation ID:
8818 to 8827
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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