[1] Peking Univ, State Key Lab Rare Earth Mat Chem & Applicat, Coll Chem & Mol Engn, Beijing 100871, Peoples R China
[2] Peking Univ, PKU, HKU,Coll Chem & Mol Engn, Joint Lab Rare Earth Mat & Bioinorgan Chem, Beijing 100871, Peoples R China
[3] Peking Univ, Electron Microscopy Lab, Beijing 100871, Peoples R China