1. Department of Chemistry, Beijing Normal University, Beijing 100875, People’s Republic of China, Fax: +86‐10‐6220‐2075
2. Laboratory of Excited States Processes, Chinese Academy of Sciences; Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130021, People’s Republic of China
3. State Key Laboratory of Rare Earth Materials Chemistry and Applications, PKU‐HKU Joint Laboratory on Rare Earth Materials and Bioinorganic Chemistry, College of Chemistry, Peking University, Beijing 100871, People’s Republic of China