1. College of Chemistry and Environmental Engineering; Shenzhen University; Shenzhen 518060 China
2. Faculty of Information Technology; Macau University of Science and Technology; Macau 519020 China
3. SZU-NUS Collaborative Innovation Center for Optoelectronic Science and Technology and Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province; Shenzhen University; Shenzhen 518060 China
4. School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA