1. School of Materials Science and Engineering Nanyang Technological University Singapore 639798 Singapore
2. Singapore-HUJ Alliance for Research and Enterprise (SHARE) Nanomaterials for Energy and Energy Water Nexus (NEW) Campus for Research Excellence and Technological Enterprise (CREATE) Singapore 138602 Singapore
3. School of Materials Science and Engineering Ocean University of China Qingdao Shandong 266100 P. R. China