Effect of surfactants on the structural, microstructural, optical, and photoluminescence characteristics of nanostructured SnO2 compounds

Abstract

This study explores how various surfactants (CTAB, PVA, and SLS) affect the properties of SnO₂ nanoparticles synthesized via co-precipitation. The impact of these surfactants on crystal structure, microstructure, and bandgap characteristics was analyzed using XRD, FE-SEM, FTIR, UV–Vis-NIR, and PL spectroscopy techniques. The phase purity was assessed using X-ray powder diffraction and Fourier-transform infrared spectroscopy (FTIR), confirming a tetragonal rutile crystal structure (P4₂/mnm (1 3 6) space group). The crystalline size was determined via Scherer and Williamson-Hall techniques. FTIR analysis identified Sn-O vibrational modes and other functional groups. Scanning electron microscopy (SEM) revealed spherical-shaped particles with a flake-like grain structure, matching the crystalline size distribution. UV–Vis absorption spectroscopy explored optical properties, determining absorbance and optical bandgap using Tauc's plot. Photoluminescence (PL) response was observed under 248 nm illumination, showing peaks (363.6–558.6 nm) attributed to near band edge emission and defect energy levels from Sn interstitials and oxygen vacancies. CIE parameters, including color coordinates (x, y), color-correlated temperature of SnO₂ nanoparticles. This study provides valuable insights into the potential applications of pure and surfactant-assisted SnO₂ nanoparticles in optoelectronics.