Tracking of structural defects induced by Eu-doping in β-Ag 2 MoO 4 : their influences on electrical properties

Abstract

In this study, several methods were employed to investigate the electrical characteristics of β-Ag2MoO4systems, both Eu-doped and undoped, synthesized using the microwave-assisted hydrothermal method.The focus extended to understanding how synthesis time influences material defects, with doping fixed at1%. A systematic shift in the silver vacancy (VAg) concentration was observed within the doped β-Ag2MoO4system. Specifically, this study demonstrated that the incorporation of Eu3+ into polycrystallineβ-Ag2MoO4 initially increases the VAg concentration. However, as the synthesis time progresses, the VAgconcentration decreases, resulting in alterations in the resulting electrical properties, arising from the intricate interplay between the number of grain boundaries and carrier density. By combining informationobtained from photoluminescence, positron annihilation lifetime spectroscopy, and impedance spectroscopy, a comprehensive conduction mechanism was formulated, shedding light on both doped andundoped β-Ag2MoO4 systems.