1. Department of Optoelectronic Information Science, School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China
2. Department of Chemistry‐Ångström Laboratory Uppsala University Uppsala SE‐751 21 Sweden
3. Department of Chemistry and Chemical Engineering Chalmers University of Technology Göteborg SE‐412 96 Sweden
4. The Key Laboratory for Ultrafine Materials of The Ministry of Education East China University of Science and Technology Shanghai 200237 China