Surfactant-Mediated Morphological and Optical Properties of SnSe Nanoparticles

The present study explores the effect of CTAB and EDTA surfactants on the morphological and optical properties of tin selenide (SnSe) nanoparticles. The pure SnSe, CTAB@SnSe, and EDTA@SnSe nanoparticles have been synthesized via a cost-effective solvothermal approach. X-ray diffraction (XRD) result confirms the orthorhombic crystal structure for all samples, and the average crystallite sizes estimated from XRD patterns are found to be 20, 21, and 22 nm for CTAB@SnSe, EDTA@SnSe, and pure SnSe nanoparticles, respectively. The field-emission scanning electron microscopy images show that the thick vertical sheets changed into flower and plate-like morphologies in the presence of the surfactants CTAB and EDTA, respectively. X-ray photoelectron spectroscopy study confirms the presence of 3d chemical states of Sn and Se in all synthesized samples. The presence of functional groups has been studied using Fourier-transform infrared spectroscopy. The UV-Vis absorption spectra show a blue shift in the band gap of synthesized samples from 1.82 to 1.95 eV with the incorporation of surfactants. The photoluminescence analysis reveals that each sample exhibits emission peaks at 389 and 468 nm due to near-bandedge emission, while emission at 558 nm is attributed to defect states. Further, a shift in the peak position and a variation in intensity have also been observed in surfactant-capped samples.