1. School of Materials and Energy National and Local Joint Engineering Laboratory for Optical Conversion Materials Lanzhou University Lanzhou 730000 China
2. School of Optoelectronic Engineering & CQUPT-BUL Innovation Institute Chongqing University of Posts and Telecommunications Chongqing 400065 China
3. Condensed Matter and Interfaces Debye Institute for Nanomaterials Science Utrecht University 3508 TA Utrecht The Netherlands