Three-dimensional architectures composed of two-dimensional atomic layer molybdenum disulphide for solar cell and self-powered photodetectors with improved performance

Abstract

Research in the physical sciences is critical to the development of new materials technologies for clean energy. Aims in the present work are to synthesise and characterise three-dimensional architectures composed of two-dimensional atomic layer molybdenum disulphide for solar cells and self-powered photodetectors with improved performance. Nanostructured molybdenum disulphide was prepared by using a spin coating method with controlled process times. Prior to each deposition, the layer was dried with hot air for 5 min. A rough, irregular and clustered surface type was generated when the number of spin coating runs was increased. This type of surface was consistent with the morphologies expected for two-dimensional atomic layer molybdenum disulphide in three-dimensional architectures. The nanoscale morphologies, composites, and electronic properties of molybdenum disulphide were examined using scanning electron microscopy, energy-dispersive X-ray spectroscopy, and micro-Raman scattering spectroscopy, respectively. Moreover, three-dimensional architecture-based prototypes for solar cells and self-powered photodetectors were designed, fabricated and tested. In photovoltaic mode, the obtained responsivity and response speed were almost 10 times larger and 20 times faster, respectively, than those recently reported for a single monolayer molybdenum disulphide-based self-powered prototype. In addition, the effects of bias, heat, humidity and a static field on the generated photocurrent and the response time were evaluated. It is expected that the newly designed prototype will exhibit exceptional properties: a broadband spectral response, a high signal-to-noise ratio and excellent stability.