Influence of Crystallinity and Reaction Integrity on the Photoresponse of Silicon-Doped Zinc Germanate Nanowires

This study successfully synthesized high aspect ratio ternary Zn₂GeO₄-doped silicon nanowires on silicon substrates using a hydrothermal method. The crystal structures of these nanowires were systematically examined at different growth temperatures (180, 200, and 220 °C) and annealing conditions, focusing on surface morphology, crystallinity, and reaction extent. The photoresponse properties of the nanowires were thoroughly evaluated. X-ray diffraction analysis revealed a ternary phase rhombohedral structure in the obtained nanowires, and the presence of doped silicon elements was confirmed through Fourier transform-infrared (FT-IR). The crystallinity of the nanowires was quantified by using the Scherrer equation, and the reaction extent was determined by analyzing the X-ray diffraction (XRD) characteristic peaks. Notably, nanowires grown at 200 °C exhibited superior photoresponse performance with lower light and dark current values and faster electron and hole recovery speeds. This study delved into the electron–hole recovery mechanism and the defect energy band, providing insightful explanations of the observed experimental results. Future research will focus on preparing nanostructures with diverse dimensions and morphologies, exploring their potential applications in combination with photodegradation and photocatalysis. In conclusion, the study successfully produced one-dimensional metal oxide nanowires with promising industrial applications and contributed to understanding how crystallinity influences their photoresponse performance.

High aspect ratio Zn₂GeO₄-doped silicon nanowires were synthesized via hydrothermal methods. Crystal structures were analyzed at various temperatures, confirming a rhombohedral structure with doped silicon. Nanowires grown at 200 °C showed superior photoresponse, with lower light/dark currents and faster electron−hole recovery. Future research will explore diverse nanostructures and applications.