Synthesis of cadmium sulfide spongy balls with nanoconduits for effective light harvesting

Thin films of cadmium sulfide (CdS) consisting of spongy balls with nanoconduits have been chemically synthesized at 70 °C from an aqueous alkaline bath onto soda lime glass and fluorine-doped tin oxide (FTO)-coated glass substrates. The synthesized spongy balls of CdS were characterized using X-ray diffraction (XRD), UV–vis spectroscopy, scanning electron microscopy (SEM), Fourier transform Raman spectroscopy (FT-Raman) and X-ray photoelectron spectroscopy (XPS). The XRD pattern revealed the formation of CdS particles with a cubic crystal structure. SEM micrographs show that the spongy ball-like morphology is composed of nanoconduits. Such spongy balls with nanoconduits that contain numerous nanowalls are a facile way to trap light. The light absorption path length of a photon increases in the nanoconduits and thus can participate in multiple scattering and absorption. This is beneficial for effective light harvesting and improvement in the power conversion efficiency of solar cells.