Electronic structure, growth and properties of hydrothermally derived crystalline Cu2MnSnS4 quantum dots: optimization of physiochemical parameters and electrochemical performance

The present article reports the synthesis, characterization and spin-polarized electronic structure of Cu2MnSnS4 (CMTS) quantum dots. Optimization of the hydrothermal physical parameters including reaction temperature and duration has been performed. The CMTS material synthesized was characterized for its structural, morphological, chemical, compositional optical and electrochemical properties. Variation of the reaction parameters made it possible to get an idea about the process of material formation. Formation mechanism, secondary phase detection and single-phase crystallinity are achieved robustly. Single phase tetragonal CMTS was synthesized just after 8 h reaction duration. Significant reactions parameters like, prolonged reaction duration and higher temperatures influence the morphology and hence resulted in enhanced crystallinity of these nanostructures. Variable structural morphologies and shapes like polygons, cauliflower and quantum dots as small as 4-5 nm were synthesized. Optical properties indicated that the quantum dots are highly active in the visible range of the optical spectrum. Also, the electronic structure calculations for this material tracked the 1.4 eV band gap confirmed from absorption spectrum. Electrochemical properties showed the material is having pseudocapacitive nature exhibiting specific capacitance of 268 F/g revealing its charge storing ability.