Novel Red Emission from MoO₃/MoS₂-MoO₂-MoO₃ Core-Shell Belt Surface

Electrically driven red emission from MoS₂-MoO₂-MoO₃ (MS-MO) hybrid-based metal-semiconductor-metal (MSM) devices is reported for the first time. MoO₃ belts with high crystal quality and sufficient size are synthesized by thermal deposition. A layer of MS-MO hybrid is then produced on the belt surface to form MoO₃/MS-MO core-shell by sulfurization. The devices exhibit unique electrical properties, a nonlinear I- V curve, and electric hysteresis characteristics at high applied biases (>2.4 V), where MS-MO hybrids act as electron transport channels. The electroluminescent current of the device increases to a set current limit over time when a constant bias is applied. The novel characteristics of the device are attributed to the space charge limited conduction (SCLC) mechanism occurring in MS-MO hybrids. The strong light emission is from recombination of excitons within the MoS₂ phase. This work develops a simple and effective method to drive MoS₂ to emit light on a large scale without using monolayer MoS₂ and vertical p-n junctions, indicating great potential for future 2D optoelectronics and photonics applications.