1. State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry CAS Changchun 130022 China
2. University of Science and Technology of China Hefei 230026 China
3. Physical Science and Engineering Division (PSE) King Abdullah University of Science and Technology (KAUST) Thuwal 23955‐6900 Saudi Arabia
4. Department of Energy Engineering Hanyang University Seoul 133‐791 Republic of Korea