A review on the preparation, microstructure, and photocatalytic performance of BiO in polymorphs

• Published in: Nanoscale 2021-11, Vol.13 (42), p.17687-17724
• Main Authors: Zahid, Abdul Hannan, Han, Qiaofeng
• Format: Article
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/d1nr03187b

In recent years, the semiconductor bismuth oxide (Bi 2 O 3 ) has attracted increasing attention as a potential visible-light-driven photocatalyst due to its simple composition, relatively narrow bandgap (2.2-2.8 eV), and high oxidation ability with deep valence band levels. Owing to the symmetry of its unit cell, Bi 2 O 3 exists in more than one crystal form and exhibits phase-dependent photocatalytic properties. However, the phase-selective synthesis of Bi 2 O 3 is a complex process, and its phase transformation usually occurs in a wide temperature range. Therefore, the development of Bi 2 O 3 phases with a controllable microstructure and good photocatalytic properties is a great challenge. Hundreds of articles have been reported on the phase-selective synthesis and photocatalytic performance of Bi 2 O 3 . However, an interacting and critical review has rarely been reported, and thus it is essential to fill the gap in the literature. In this review, the phase-dependent photocatalytic performance of Bi 2 O 3 is presented in detail. The phase-selective synthesis and temperature-dependent phase stability of highly active Bi 2 O 3 are explored. The phase junction in Bi 2 O 3 is reviewed, and the future perspective with an outlook on contemporary challenges is provided finally. The primitive and advanced approaches for the synthesis of various Bi 2 O 3 polymorphs for photocatalytic applications are reviewed. The temperature-dependent phase transformation, morphology, and phase junction in Bi 2 O 3 phases are presented.