A brief study on structural, optical, and photovoltaic properties of lithium sulfate monohydrate single crystals

Abstract

In the current study, single crystals of lithium sulfate monohydrate (LSMH) were grown by slow evaporation method. For structural analysis, these crystals were characterized by X-Ray diffraction, the optical properties were studied by UV–Vis–NIR and photoluminescence spectroscopy, and vibrational studies were studied by Fourier Transform Infrared spectroscopy. The XRD analysis reveals that this understudy crystal belongs to monoclinic system with P21/a space group. The FT-IR data indicate various functional groups associated with the established crystal structure of the crystal. From the optical absorption studies of these crystals, various parameters, such as optical band gap, disorder coefficient, disorder energy, nature of transition etc. These grown samples show good optical transmittance with wide optical band gap. This crystal shows PL emission lines in green, orange, and red part of visible spectrum when excited by the ultraviolet photons. Further, a simple diode of this crystal was also developed, and this prepared device was subjected to Current–voltage characterizations in dark and in the presence of various colors of light photons. The present material shows negative photoconductivity. Effect of light on photocapacitance of this prepared device was also studied. The defects or traps in the band structure of this material could be the best reason for this observed behavior. The present material also shows good thermal stability in the considerable range of temperature. A good interrelation among these various studied parameters was observed. The observed optical, electrical, and thermal properties of this crystal project it as a good candidate for modern electronic applications.