TY - JOUR
T1 - From Titanium Sesquioxide to Titanium Dioxide
T2 - Oxidation-Induced Structural, Phase, and Property Evolution
AU - Li, Yangyang
AU - Yang, Yang
AU - Shu, Xinyu
AU - Wan, Dongyang
AU - Wei, Nini
AU - Yu, Xiaojiang
AU - Breese, Mark B.H.
AU - Venkatesan, Thirumalai
AU - Xue, Jun Min
AU - Liu, Yichen
AU - Li, Sean
AU - Wu, Tom
AU - Chen, Jingsheng
N1 - Funding Information:
This work is supported by the Singapore National Research Foundation under CRP Award NRF-CRP10-2012-02. The authors acknowledge the Singapore Synchrotron Light Source (SSLS) for providing the facility necessary for conducting the research. The laboratory is part of the National Research Infrastructure under the Singapore National Research Foundation.
Publisher Copyright:
© Copyright 2018 American Chemical Society.
PY - 2018/7/10
Y1 - 2018/7/10
N2 - In contrast to Ti4+-containing titanium dioxide (TiO2), which has a wide bandgap (∼3.0 eV) and has been widely explored for catalysis and energy applications, titanium sesquioxide (Ti2O3) with an intermediate valence state (Ti3+) possesses an ultranarrow bandgap (∼0.1 eV) and has been much less investigated. Although the importance of Ti3+ to the applications of TiO2 is widely recognized, the connection between TiO2 and Ti2O3 and the transformation pathway remain unknown. Herein, we investigate the oxidation-induced structural, phase, and property evolution of Ti2O3 using a complementary suite of microscopic and spectroscopic tools. Interestingly, transformation pathways to both rutile and anatase TiO2 are identified, which sensitively depend on oxidation conditions. Unique Ti2O3/TiO2 core-shell structures with annealing-controlled surface nanostructure formation are observed for the first time. The compositional and structural evolution of Ti2O3/TiO2 particles is accompanied by continuously tuned optical and electrical properties. Overall, our work reveals the connection between narrow-bandgap Ti3+-containing Ti2O3 and wide-bandgap Ti4+-containing TiO2, providing a versatile platform for exploring photoelectrocatalytic applications in valence- and structure-tailored oxide materials.
AB - In contrast to Ti4+-containing titanium dioxide (TiO2), which has a wide bandgap (∼3.0 eV) and has been widely explored for catalysis and energy applications, titanium sesquioxide (Ti2O3) with an intermediate valence state (Ti3+) possesses an ultranarrow bandgap (∼0.1 eV) and has been much less investigated. Although the importance of Ti3+ to the applications of TiO2 is widely recognized, the connection between TiO2 and Ti2O3 and the transformation pathway remain unknown. Herein, we investigate the oxidation-induced structural, phase, and property evolution of Ti2O3 using a complementary suite of microscopic and spectroscopic tools. Interestingly, transformation pathways to both rutile and anatase TiO2 are identified, which sensitively depend on oxidation conditions. Unique Ti2O3/TiO2 core-shell structures with annealing-controlled surface nanostructure formation are observed for the first time. The compositional and structural evolution of Ti2O3/TiO2 particles is accompanied by continuously tuned optical and electrical properties. Overall, our work reveals the connection between narrow-bandgap Ti3+-containing Ti2O3 and wide-bandgap Ti4+-containing TiO2, providing a versatile platform for exploring photoelectrocatalytic applications in valence- and structure-tailored oxide materials.
UR - http://www.scopus.com/inward/record.url?scp=85048748336&partnerID=8YFLogxK
U2 - 10.1021/acs.chemmater.8b01739
DO - 10.1021/acs.chemmater.8b01739
M3 - Article
AN - SCOPUS:85048748336
SN - 0897-4756
VL - 30
SP - 4383
EP - 4392
JO - Chemistry of Materials
JF - Chemistry of Materials
IS - 13
ER -