Sodium doping in brookite TiO₂ enhances its photocatalytic activity

• Boxiang Zhuang,
• Honglong Shi,
• Honglei Zhang and
• Zeqian Zhang

Beilstein J. Nanotechnol. 2022, 13, 599–609, doi:10.3762/bjnano.13.52

• Boxiang Zhuang Honglong Shi Honglei Zhang Zeqian Zhang School of Science, Minzu University of China, 27 Zhong guancun South Avenue, Haidian District, Beijing, 100081, People's Republic of China 10.3762/bjnano.13.52 Abstract We report in this work that sodium doping of brookite TiO2 effectively

• structure and produce microstructures such as the core–shell structure, local lattice distortion, interstitial atoms, and atomic vacancies, which are critical to its excellent photocatalytic activity. Keywords: brookite titanium dioxide; core–shell structure; photocatalytic activity; sodium doping; twins

• sodium doping can stabilize the brookite NaxTi1−xO2 up to 500 °C. At 600 °C, sodium in the brookite precipitates in the form of Na2CO3 and above 700 °C, the brookite NaxTi1−xO2 directly transforms into the Na2Ti6O13 phase via a twining process. The twinning structure is formed by successively displacing