Funding for this research was provided by:
The National Natural Science Foundation of China (Grant No. 21071115)
The Shaanxi Province Natural Science Foundation Research Project (Grant No. 2016JZ006)
The Education Committee of Shaanxi Province (No. 16JS112)
The Shaanxi Light Optoelectronics Material Co., Ltd (No. 2015610002001920)
Article History
Received: 4 November 2017
Accepted: 14 January 2018
First Online: 24 January 2018