1. CAS Key Laboratory of Renewable EnergyGuangdong Key Laboratory of New and Renewable Energy Research and DevelopmentGuangzhou Institute of Energy ConversionChinese Academy of Sciences Guangzhou 510640 P.R. China
2. University of Chinese Academy of Sciences Beijing 100049 P.R. China
3. Department of ChemistryUniversity of Science and Technology of China Hefei 230026 P.R. China
4. Shanxi Engineering Research Center of BiorefineryInstitute of Coal ChemistryChinese Academy of Sciences Taiyuan 030001 P.R. China
5. National Synchrotron Radiation LaboratoryUniversity of Science and Technology of China Hefei 230029 P.R. China