1. Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake ResourcesQinghai Institute of Salt LakesChinese Academy of Sciences Xining 810008 China
2. College of Materials Science and Opto-electronic TechnologyCenter of Materials Science and Optoelectronics EngineeringUniversity of Chinese Academy of Sciences Beijing 100049 China
3. Department of MaterialsImperial College LondonRoyal School of Mines Exhibition Road London SW7 2AZ UK