Aqueous Synthesis of Mesostructured BiVO₄ Quantum Tubes with Excellent Dual Response to Visible Light and Temperature

Analysis of the atomic structure of monoclinic BiVO₄ reveals its fascinating structure-related dual response to visible light and temperature. Although there have been a few reported studies of its responses to visible light and temperature, an understanding of the effects of quantum size, particle shape or specific exposed facets on its dual responsive properties remains elusive; this is primarily due to the limited availability of high-quality monodisperse nanocrystals with extremely small sizes and specific exposed facets. Herein, we describe a novel assembly-fusion strategy for the synthesis of mesostructured monoclinic BiVO₄ quantum tubes with ultranarrow diameter of 5 nm, ultrathin wall thickness down to 1 nm and exposed {020} facets, via a convenient hydrothermal method at temperatures as low as 100 ℃. Notably, the resulting high-quality quantum tubes possess significantly superior dual-responsive properties compared with bulk BiVO₄ or even BiVO₄ nanoellipsoids, and thus, show high promise for applications as visible-light photocatalysts and temperature indicators offering improved environmental quality and safety. This mild and facile methodology should be capable of extension to the preparation of other mesostructured inorganic quantum tubes with similar characteristics, giving a range of materials with enhanced dual-responsive properties.