Recently, Associate Prof. Xia Jiexiang from the School of Chemistry and Chemical Engineering published a research paper in Advanced Materials (IF=25.809), through the collaboration with Professor Zheng Liu from Nanyang Technological University in Singapore and Dr. Shi-Ze Yang from Oak Ridge National Laboratory. The title is Defect-Tailoring Mediated Electron-Hole Separation in Single Unit Cell Bi₃O₄Br Nanosheets for Boosting Photocatalytic Hydrogen Evolution and Nitrogen Fixation (Advanced Materials, 2019, 31, 1807576), in which Advanced Materials is an internationally authoritative journal in the field of material chemistry. Jiangsu University is the first institution of this paper, and Dr. Jun Di is the first author.

Solar photocatalysis is a potential solution to satisfying energy demand and its resulting environmental impact. However, the low electron-hole separation efficiency in semiconductors has slowed the development of this technology. The effect of defects on electron-hole separation is not always clear. A model atomically thin structure of single-unit-cell Bi₃O₄Br nanosheets with surface defects is proposed to boost photocatalytic efficiency by simultaneously promoting bulk- and surface-charge separation. Defect-rich single-unit-cell Bi₃O₄Br displays 4.9 and 30.9 times enhanced photocatalytic hydrogen evolution and nitrogen fixation activity, respectively, than bulk Bi₃O₄Br. After the preparation of single-unit-cell structure, the bismuth defects are controlled to tune the oxygen defects. Benefiting from the unique single-unit-cell architecture and defects, the local atomic arrangement and electronic structure are tuned so as to greatly increase the charge separation efficiency and subsequently boost photocatalytic activity. This strategy provides an accessible pathway for next generation photocatalysts.