1. Chongqing Key Laboratory of Inorganic Functional Materials, College of Chemistry, Chongqing Normal University, Chongqing 401331, P. R. China
2. School of Chemistry and Materials, Guizhou Normal University, Guiyang, Guizhou 550025, P. R. China
3. Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Chemical Engineering of Guangxi Normal University, Guilin 541004, P.R. China