Deoxygenation-Controlled Synthesis of ZnO Nanoparticles via Non-Thermal Plasma Jet for Optoelectronic Applications

Abstract

The present study explores the impact of oxygen reduction on the structural, electrical, and optoelectronic properties of zinc oxide nanoparticles (ZnO NPs) synthesized using non-thermal plasma jet (NTPJ), which used deionized water (DW) as the interaction medium. Four methods were used to test that. The first one was left DW without any treatment (M1). The second was DW treated with argon treatment for 10 min before use in NPs synthesis (M2). In contrast, in the third method, argon treatment was applied to DW during the entire synthesis process (M3). In the fourth one, DW was heated at 100°C and subjected to continuous argon flow during the synthesis process (M4). The characterization of zinc nanoparticles on glass and silicon was conducted using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and scanning electron microscopy (SEM). The EDX analysis revealed zinc: oxygen atomic ratio of 1:1, which is the stoichiometric ratio, at method M4, reducing defects and improving material properties.

The results showed highly crystalline hexagonal wurtzite of synthesized ZnO NP, with varying crystallite sizes depending on the substrate type. SEM images showed improved air permeability and aerosolization properties compared to samples with less oxygen reduction. Si/ZnO NP photodetector performance is more significant in the case of ZnO NPs synthesized in method M4, with a responsivity of 18.3 A/W and a quantum efficiency reaching nearly 40% at 330 nm wavelength.