Nebulizer-assisted spray pyrolysis development of rare earth (Pr3+) doped In2S3 thin films for an intense ultraviolet photocurrent response

Developing In2S3nanolayers using the cost-effective approach for light-current conversion has grown last decays. In this work, we report the high photo-current of indium sulfide (In2S3) thin films having different praseodymium (Pr) contents (0, 1, 2, 3, 4, and 5 wt %) using high-purity indium chloride and thiourea as the source. The optical absorption, crystal structure, surface appearance, defect-related emission, and photoconductivity of the prepared In2S3: Pr thin films were examined by several characterization techniques. X-ray Diffraction (XRD) measurements demonstrate a cubic structure of the polycrystalline nature of the synthesized films with a preferential (220) growth orientation. The selected Pr dopant enhances the grain size of the In2S3 thin film from 48 to 66 nm and hence, benefits the photosensor properties. Field emission scanning electron microscope (FESEM) images confirms the development of interconnected ball-shaped nanograins. The room temperature photoluminescence (PL) spectra exemplify the presence of violet and green emission at 470 and 521nm. The developed In2S3:Pr thin films exhibited good absorption in the UV region. Pr addition helped in narrowing the bandgap values from 2.91 to 2.83 eV. Among the different doping yields, the 3%Pr doped In2S3 film shows excellent I–V characteristics and offered a satisfactory external quantum efficiency (495%), pronounced photo responsivity (2.12A/W) and impressive detectivity (1.54 × 1011 Jones) own to the enhanced light-matter interactions. The present results provide a new platform for future photosensor applications.