Photo-induced nucleation of rutile nanorods-an ignored parameter in crystallization

This work presents a surfactant-free and economical sol-gel method to synthesize multi-branched rutile TiO(2) nano-trees. Simple illumination by incandescent light during synthesis causes numerous branches to grow from the sides of nanorods, this process is accompanied by hydroxylation of the crystal surface. A {101} twin is demonstrated to connect the trunk to the branches. The extents of branching and surface hydroxylation are controlled by either photo-illumination or the addition of an exciton scavenger (H(2)O(2)). The relationship between the quantity of the branches and the excitons can be elucidated by considering photo-induced defects.