Influence of Coomassie Brilliant Blue dye Doping on the Physical Properties of Hydrothermally Synthesized Cu-Sb-S Nanocomposites

This research examines the effects of Coomassie Brilliant Blue (CBB) incorporation on Cu-Sb-S nanocomposite thin films synthesized through hydrothermal methods. Samples were prepared with varying CBB concentrations (0, 0.01, 0.03, and 0.05 gm) and comprehensively known to have structural, morphological, optical, and electronic characteristics. XRD analysis successfully verified forming crystalline phases, with patterns showing characteristic peaks that evolved with increasing CBB content. Based on the X-ray diffraction results. The crystal formations of the products, Cu3SbS3, Cu3SbS4, and Na2C2O4, are cubic, Tetragonal, and Monoclinic symmetry respectively. FE-SEM imaging revealed a uniform nanostructure distribution and controlled morphology across all compositions, confirming successful CBB integration into the host matrix. Optical characterization demonstrated systematic modifications in the transmission and absorption properties with an increasing CBB concentration, indicating effective band structure modification. The optical direct band gab values were proved UV-visible absorption to be 1.4,1.5,1.6 and 1.7 eV were estimated by Tauc plots for ratio (X= 0,0.01,0.03,0.05 gm) respectively. Hall effect measurements revealed p-type semiconductor behavior throughout the composition range, with a notable trend of a decreasing carrier concentration from 9.53×10¹⁴ to 3.21×10¹⁴ cm⁻³ accompanied by a significant enhancement in carrier mobility from 4.231 to 27.654 cm²/V·s as the CBB content increased. These findings demonstrate a successful modification of the Cu-Sb-S system's optoelectronic properties through CBB incorporation, suggesting potential applications in photovoltaic devices and optoelectronic systems requiring high carrier mobility. It can also be used as a good absorbent layer in solar cells.