In-situ synthesis of amorphous H 2 TiO 3 -modified TiO 2 and its improved photocatalytic H 2 -evolution performance

Surface cocatalyst modification is considered as one of the most ideal strategies for improved photocatalytic H -evolution activity of photocatalysts. It is quite important to develop new cocatalyst and to enhance the interfacial coupling between cocatalysts and photocatalysts with the aim of promoting the rapid transfer of photogenerated charge. In this work, amorphous H TiO (a-H TiO ) nanoparticles (ca. 1 nm), as a novel and effective hole cocatalyst, were homogeneously in-situ generated on TiO surface (the sample was referred as a-H TiO /TiO ) via a first controllable surface reaction of TiO in a NaOH solution and the following ion-exchange reaction with HCl solution at room temperature. The resultant a-H TiO /TiO photocatalysts exhibited greatly enhanced photocatalytic H -evolution performance compared with pure TiO , which was mainly attributed to amorphous H TiO nanoparticles as hole cocatalysts for rapid hole transfer. To further promote the photocatalytic activity of a-H TiO /TiO , Ni(OH) as electron cocatalysts was loaded on the surface of a-H TiO /TiO to prepare the co-modified a-H TiO /TiO /Ni(OH) photocatalyst. The results indicated that the H -evolution performance of the a-H TiO /TiO /Ni(OH) photocatalyst was significantly higher than that of a-H TiO /TiO by a factor of 66.7 due to the synergy of a-H TiO and Ni(OH) cocatalysts. This study provides a strategic approach for enhanced H -evolution activity by enhanced interfacial coupling between cocatalysts and photocatalysts.