Large area MoS2 films fabricated via sol-gel used for photodetectors

Two-dimensional molybdenum disulfide (2D-MoS2) has been extensively exploited to fabricate devices for applications ranging from optoelectronics to gas sensing and energy harvesting. The major limitations in the production of 2D-MoS2 regard the scalability and reproducibility of the fabrication limiting the possibility to produce large area devices. In order to bridge the scalability needs with facile fabrication techniques, solution processed MoS2 has recently been explored as a possible pathway. In this work, we optimized a recipe for the making of MoS2 films through sol-gel synthesis. The new recipe allows for the deposition of large area (~cm2) MoS2 films on various dielectric and metallic substrates. The obtained MoS2 films are investigated through a wide range of characterization techniques that demonstrate that the films display chemical and physical properties expected for 2D-MoS2. Moreover, the properties are found to be homogeneous all over the film area. In order to test the material in practical applications, we fabricated and characterized photodetector devices. The photodetectors display responsivity values of few mA/W in the NUV-VIS-NIR spectrum, widening the spectral response of previously reported MoS2 based photodetectors. Although the device response time and light-to-dark current ratio are affected by residual electronic defects in the material, this work demonstrates a scalable and versatile process to fabricate 2D-MoS2 and photodetectors based thereof.