title: Solution-Grown ZnO Films toward Transparent and Smart Dual-Color Light-Emitting Diode.
abstract: An individual light-emitting diode (LED) capable of emitting different colors of light under different bias conditions not only allows for compact device integration but also extends the functionality of the LED beyond traditional illumination and display. Herein, we report a color-switchable LED based on solution-grown n-type ZnO on p-GaN/n-GaN heterojunction. The LED emits red light with a peak centered at ∼692 nm and a full width at half-maximum of ∼90 nm under forward bias, while it emits green light under reverse bias. These two lighting colors can be switched repeatedly by reversing the bias polarity. The bias-polarity-switched dual-color LED enables independent control over the lighting color and brightness of each emission with two-terminal operation. The results offer a promising strategy toward transparent, miniaturized, and smart LEDs, which hold great potential in optoelectronics and optical communication.
authors.affiliation: Institute of Materials Research and Engineering , Agency for Science, Technology and Research, Singapore 138634, Singapore.
authors.forename: Xiaohu
authors.initials: X
authors.lastname: Huang
authors.affiliation: Singapore-MIT Alliance for Research and Technology , Singapore 138602, Singapore.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Institute of Materials Research and Engineering , Agency for Science, Technology and Research, Singapore 138634, Singapore.
authors.forename: Shijie
authors.initials: S
authors.lastname: Wang
authors.affiliation: Institute of Materials Research and Engineering , Agency for Science, Technology and Research, Singapore 138634, Singapore.
authors.forename: Dongzhi
authors.initials: D
authors.lastname: Chi
authors.affiliation: Singapore-MIT Alliance for Research and Technology , Singapore 138602, Singapore.|Department of Electrical and Computer Engineering, National University of Singapore , Singapore 117576, Singapore.
authors.forename: Soo Jin
authors.initials: SJ
authors.lastname: Chua
keywords: ZnO; defects; electroluminescence; photoluminescence; smart light-emitting diode; solution growth