Water-Mediated Efficient Synthesis of Bismuth Oxyiodide for Several Distinct Morphologies

It is highly desirable to synthesize various micro/nanostructures of bismuth oxyhalide by facile methods and further investigating these functional photoactive materials. Herein, we demonstrate a facile route to synthesize five distinct morphologies of BiOI microstructures via the solvothermal method. Notably, based on the morphology study of intermediate products and crystal structure analysis of BiOI microstructures, the mechanism of water effect to modulate the crystal growth, and finally mediate the morphology of BiOI microstructures was proposed. It is demonstrated that water can control the crystal growth transformed from vertical to (001) facets to parallel it with the increase of its amount. Combined with the Ostwald ripening crystal reconstruction and self-assembly of nanostructures, the microstructures of BiOI can be precisely controlled. Therefore, the water-mediated strategy not only gives a new route for specific BiOI microstructures preparation but also provides new evidence for further understanding of the crystal growth mechanism of BiOI by the wet-chemical method.