DEVELOPMENT AND OPTIMIZATION OF TIN OXIDE (SNO₂)-BASED HYBRID NANOSTRUCTURES FOR USE AS COST-EFFECTIVE TRANSPARENT CONDUCTING ELECTRODES

Abstract

Transparent conducting electrodes (TCEs) are essential components in modern optoelectronic devices such as solar cells, touch screens, smart windows, light-emitting diodes, and thin-film transistors. However, the high cost and limited availability of conventional indium tin oxide (ITO) materials have created the need for alternative low-cost transparent conducting materials. This study focused on the development and optimization of fluorine-doped tin oxide (FTO)-based hybrid nanostructures integrated with silver (Ag) thin films for application as cost-effective transparent conducting electrodes. The synthesized thin films were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet–visible (UV–Vis) spectroscopy, and electrical characterization techniques to evaluate their structural, morphological, optical, and electrical properties. The XRD analysis confirmed the successful formation of highly crystalline FTO and Ag thin films. The FTO films exhibited polycrystalline tetragonal SnO₂ structures, while the Ag films showed strong crystalline orientation and enhanced structural ordering. SEM analysis revealed that the FTO films possessed interconnected granular morphologies with moderate porosity and surface roughness, whereas the Ag thin films exhibited smooth, compact, and densely packed surface structures favourable for electrical conduction. Optical characterization showed that the FTO thin films possessed high optical transmittance within the visible region and low absorbance, confirming their suitability as transparent electrode materials. In contrast, the Ag thin films demonstrated strong absorbance and metallic optical behaviour associated with enhanced free-electron interaction and plasmonic effects. Electrical characterization revealed that the Ag thin films exhibited significantly higher carrier concentration, mobility, and conductivity, alongside lower resistivity and sheet resistance compared to the FTO thin films. The combined structural, optical, and electrical results demonstrate that the Ag/FTO hybrid nanostructures possess complementary properties capable of simultaneously achieving good optical transparency and enhanced electrical conductivity. The study therefore establishes the strong potential of SnO₂-based hybrid nanostructures as efficient, scalable, and low-cost alternatives to conventional ITO transparent conducting electrodes for advanced optoelectronic applications.