1. Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, P. R. China
2. Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, P. R. China
3. Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, P.R. China
4. University of Chinese Academy of Sciences, Beijing 100049, P.R. China
5. Laboratory of Basic Research in Biomass Conversion and Utilization, Department of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei 230026, P. R. China