View article

Particle size is generally considered to be the primary factor in the design of nanocrystal photocatalysts, because the reduction of particle size increases the number of active sites. However, the benefit from the size reduction can be canceled by a higher electron−hole recombination rate due to the confined space in sphere-shaped nanoparticles. Here we report a mechanistic study on a novel nanobelt structure that overcomes the drawback of sphere-shaped nanoparticles. Single-crystalline anatase TiO₂ nanobelts with two dominant surfaces of (101) facet exhibit enhanced photocatalytic activity over the nanosphere counterparts with an identical crystal phase and similar specific surface area. The ab initio density functional theory (DFT) calculations show that the exposed (101) facet of the nanobelts yields an enhanced reactivity with molecular O₂, facilitating the generation of superoxide radical. Moreover, the …