Enhancing defect densities in SmErxFe1-xO3 nanostructures and tuning their electrical characteristics for photocatalytic and photoresponse functions

Abstract

Owing to their distinct physicochemical traits nanostructured semiconductors continue to find immense potential in energy and environment friendly applications. From this point, SmErxFe1-xO3 systems were chemically synthesized and studied in detail for their photoresponse performance and photocatalytic behavior. The material characteristics were initially studied using several analytical tools that include X-ray diffraction (XRD), Raman and microscopic (SEM/TEM) instruments. Substitution of erbium (Er) ions at Fe sites was conceived using X-ray photoelectron spectroscopic (XPS) analysis. Optical band gap and their associated defect states in perovskites (upon Er replacement) was additionally evaluated using UV and PL data. Photocatalytic efficiency of SmErxFe1-xO3 was at first adjudged through comparative studies with SmFeO3 by involving effective treatment of organic dyes under visible light. Secondly, improved electrical conductivity in SmErxFe1-xO3 was capitalized on to fabricate p-n devices that demonstrated remarkable photoelectrical performance. Forward current and response ratio improved significantly in such devices. The bias conditions were also noted to proportionately improve the photo switching potential. Time-dependent photoresponse results affirmed the stability in processed devices. The improved application performance in SmErxFe1-xO3 nanostructures has been reasoned to effective substitution of Er ions, which tend to influence the O-Fe-O interactions and result with the observed electrical characteristics to facilitate the much needed improved charge transfer process.

Keywords

• Perovskites
• Nanostructures
• Photoresponse
• Photocatalysis