Tin dioxide is an ideal candidate material for optoelectronic devices, with its direct wide band gap, earth-abundance, and stability benefiting from high exciton binding energy. However, the possibility was primarily limited by its selection-rule-forbidden direct transition. In this work, the luminescence capability is unbounded with developed methods that require no extrinsic doping, demonstrating visible photoluminescence with colors ranging from orange to white. Furthermore, the density functional theory calculations have unveiled the mechanism of the achieved phenomena that empower broad applications.

Wei-Lun Xu, Ph.D. degree in Physics from National Taiwan University in 2009. He is currently a research fellow at Solar Energy Research Institute of Singapore, National University of Singapore. His research interests include the area of computational physics, optoelectronics and photovoltaics