Multifunctional MoS2 Transistors with Electrolyte Gel Gating

Abstract

MoS₂ , one of the most valued 2D materials beyond graphene, shows potential for future applications in postsilicon digital electronics and optoelectronics. However, achieving hole transport in MoS₂ , which is dominated by electron transport, is always a challenge. Here, MoS₂ transistors gated by electrolyte gel exhibit the characteristics of hole and electron transport, a high on/off ratio over 10⁵ , and a low subthreshold swing below 50 mV per decade. Due to the electrolyte gel, the density of electrons and holes in the MoS₂ channel reaches ≈9 × 10¹³ and 8.85 × 10¹³ cm^-2 , respectively. The electrolyte gel-assisted MoS₂ phototransistor exhibits adjustable positive and negative photoconductive effects. Additionally, the MoS₂ p-n homojunction diode affected by electrolyte gel shows high performance and a rectification ratio over 10⁷ . These results demonstrate that modifying the conductance of MoS₂ through electrolyte gel has great potential in highly integrated electronics and optoelectronic photodetectors.

Keywords: MoS2 ambipolar FETs; MoS2 p-n homojunction; field-programmable doping; negative photoconductive detection.