Synthesis, properties and applications of titanium-oxide clusters in water

Titanium-oxide clusters (TOCs) are a class of molecular analogues of nano-TiO2 which comprise discrete Ti-oxide cores and passivating ligands. Due to novel molecular structures and excellent photo-response, the synthesis, property and application of TOCs have attracted much attention during the last decade. In this minireview, we focus on the aqueous TOCs, a branch of metal-oxide clusters (also known as polyoxometalates), which are generally manipulated in water. In the first section, the synthesis strategy, synthesis systems and examples of aqueous TOCs are introduced. In the second part, the water-solubility and structural integrity of TOCs in solutions are discussed. The third part, the potential applications of aqueous TOCs are elaborated. Finally, a perspective of the future directions of aqueous TOCs is put forward.