Controllable Porosity of Monodispersed Tin Oxide Nanospheres via an Additive-Free Chemical Route

Tin dioxide (SnO 2 ) nanospheres with various degrees porosity have been successfully synthesized via a facile, easily scalable, and tunable hydrothermal process. The employed method requires no physical templates or environmentally unfriendly additives. Elimination of additives was favorably found to increase the specific surface area and reduce the organic contamination issue in the end product. Investigation of the controllable synthesis and growth mechanism provides valuable insights into studies of the fundamental properties of mesoporous tin oxides nanospheres. The as-synthesized mesoporous SnO 2 nanospheres are composed of numerous small nanocrystallites ∼5−10 nm and possess good size uniformity and large specific surface areas, making them excellent candidates for use in industrial applications such as gas sensors, catalysts, and biomedical drug therapy.