Synergy of Bulk Defects and Surface Defects on TiO 2 for Highly Efficient Photocatalytic Production of H 2 O 2 .

Artificial photosynthesis of H 2 O 2 by TiO 2 -based semiconductors is a promising approach for H 2 O 2 production. However, the efficiency of pristine TiO 2 is still limited by rapid charge separation and low O 2 adsorption capacity. Here, we found that the synergy between bulk and surface defects on TiO 2 could overcome this demanding bottleneck. The introduced bulk defects act as hole acceptors to induce directional hole transfer, efficiently boosting electron-hole separation. Furthermore, the adsorption of O 2 is strengthened by the introduced surface defects. Consequently, this synergy of bulk and surface defects on TiO 2 significantly improves the photocatalytic performance, with a H 2 O 2 production rate of 4560 μmol h -1 g -1 , outperforming most reported TiO 2 -based photocatalysts. This work not only provides a new insight into the mechanism of surface/bulk defects in photocatalysis but also highlights that surface/bulk regulation holds great promise for achiveing efficient photocatalytic conversion.