Under the leadership of one of the Chief Scientists in our Center, Prof. Can Li,a member of Chinese Academy of Sciences (MCAS) from Dalian Institute of Chemistry and Physics (DICP) of CAS, Prof. Li’s research group conducted the research in the field of photocatalyst for solar energy, which shows photogenerated electrons and holes can be separated between the different facets of semiconductor crystals. This finding may be useful in semiconductor physics and chemistry to construct highly efficient solar energy conversion systems. Their result has been published in the Nature Communications. Here the first author is one of the Postgraduate students recommended by XMU. Therefore, this achievement has demonstrated that the idea of creation of Collaborative Innovation Center is useful and productive.

Charge separation has a key role in determining solar energy conversion efficiency of semiconductor-based systems for producing solar electricity and solar fuels through solar cells, photoelectrocatalysisand photocatalysis. As a key step in energy conversion, electron-hole pairs generated by light absorption need to be separated and transferred to the surface of the semiconductors. Hence, an in-depth understanding of charge separation within semiconductors is desirable for the construction of an efficient solar energy conversion system. Here they show, using monoclinic bismuth vanadate crystal as a model photocatalyst, that efficient charge separation can be achieved on different crystal facets, as evidenced by the reduction reaction with photogenerated electrons and oxidation reaction with photogenerated holes, which take place separately on the {010} and {110} facets under photo-irradiation. Based on this finding, the reduction and oxidation cocatalysts are selectively deposited on the {010} and {110} facets respectively, resulting in much higher activity in both photocatalytic and photoelectrocatalytic water oxidation reactions, compared with the photocatalyst with randomly distributed cocatalysts.The findings of functional redox facets, selective deposition of redox cocatalysts on the different facets of a single crystal, and efficient charge separation between different facets should be promising and intriguing for understanding the mechanism of photocatalytic reactions, and designing highly efficient solar energy conversion photocatalysts/devices

Resource: http://www.nature.com/ncomms/journal/v4/n2/full/ncomms2401.html

Chinese Reference: http://www.dicp.ac.cn/xwzx/kjdt/201302/t20130206_3762446.html