Sheng Yuewen, Chen Tongxin, Lu Yang, Chang Ren-Jie, Sinha Sapna, Warner Jamie H
Department of Materials , University of Oxford , Parks Road , Oxford OX1 3PH , United Kingdom.
ACS Nano. 2019 Apr 23;13(4):4530-4537. doi: 10.1021/acsnano.9b00211. Epub 2019 Mar 21.
The solid progress in the study of a single two-dimensional (2D) material underpins the development for creating 2D material assemblies with various electronic and optoelectronic properties. We introduce an asymmetric structure by stacking monolayer semiconducting tungsten disulfide, metallic graphene, and insulating boron nitride to fabricate numerous red channel light-emitting devices (LEDs). All the 2D crystals were grown by chemical vapor deposition (CVD), which has great potential for future industrial scale-up. Our LEDs exhibit visibly observable electroluminescence (EL) at both 5.5 V forward and 7.0 V backward biasing, which correlates well with our asymmetric design. The red emission can last for at least several minutes, and the success rate of the working device that can emit detectable EL is up to 80%. In addition, we show that sample degradation is prone to happen when a continuing bias, much higher than the threshold voltage, is applied. Our success of using high-quality CVD-grown 2D materials for red light emitters is expected to provide the basis for flexible and transparent displays.
对单一二维（2D）材料的深入研究为开发具有各种电子和光电特性的二维材料组件奠定了基础。我们通过堆叠单层半导体二硫化钨、金属石墨烯和绝缘氮化硼引入不对称结构，以制造大量红色通道发光器件（LED）。所有二维晶体均通过化学气相沉积（CVD）生长，这对于未来的工业规模扩大具有巨大潜力。我们的LED在正向5.5 V和反向7.0 V偏压下均表现出明显可见的电致发光（EL），这与我们的不对称设计高度相关。红色发射可持续至少几分钟，能够发射可检测EL的工作器件成功率高达80%。此外，我们表明，当施加远高于阈值电压的持续偏压时，样品容易发生降解。我们成功地将高质量CVD生长的二维材料用于红色发光体，有望为柔性和透明显示器提供基础。
