Steered electrical pathways of plasmonic metal-semiconductor heterostructures via crystal-phase-dependent selective deposition

Plasmon mediated heterojunction with tunable and superior photoelectrical performance is an intriguing approach to improve light harvesting in photocatalysis. However, the low separation efficiency and uncertain diffusion directions of charges remained still a challenge to meet desired photocatalytic process. To overcome these issues, in this work, we showed the crystal-phase-dependent effects of the semiconductor for hot-electrons transfer assisted by plasmonic heterostructures under visible light by using Au–P25 as a model. It was found that Au–P25 formed by Au-anatase-rutile was greatly advantageous over that of Au-rutile-anatase for the hot-electrons separation and transportation (∼3 folds increase in photocurrents density). Such differences may account for the suitable band alignment mediated by selective crystal phase contact, which forming a convenient pathway for fluent electrons transfer caused by the smaller interfacial energy barrier in Au-anatase-rutile, comparing to that in Au-rutile-anatase. Such results might offer some useful contributions to the future design of nanomaterials for plasmon-mediated photoelectrical or photochemical applications.