Ultrathin porous Bi5O7X (X = Cl, Br, I) nanotubes for effective solar desalination

Abstract

Seawater desalination is an effective method to solve the water resource crisis, which is more critical than the energy crisis to some extent. However, the existing technologies for desalination are highly energy-consuming, inefficient, or complicated and thus, a better method needs to be designed. Here, ultrathin porous bismuth oxyhalide nanotubes are separately synthesized by a general and fast method for the first time. They have abundant pores and oxygen vacancies, and the Na⁺ and Cl⁻ ions can accumulate around the surface of the sample under sunlight for desalination. The ultrathin porous Bi₅O₇I nanotubes exhibit better performance (33.65 mg g⁻¹) and stability. This study offers a convenient and sustainable approach for solar desalination.