Efek Holding Time Terhadap Struktur Sifat Listrik dan Megnetik ZnO Didop Ni

Abstract

Study effect of Ni doped ZnO with sintering temperature holding time variations (2, 4 and 8 hours) and Ni concentration (1, 3 and 5% at) has been synthesized using solid-state reaction method and High-Speed Shaker Mill. XRD results showed that the overall samples results showed the ZnO hexagonal wurtzite main structure. However, the increasing of Ni concentration to 3% and 5% atom with holding time 2, 4 and 8 hours presented the impurity phase. The diffraction peak shift on plane (1 0 0) toward the 2 tetha corner weas enlarge, while diffraction intensity and FWHM was decreased for each Ni doped ZnO samples. Furthermore, it resulted the increasing on average crystallite size and holding time. Based on the resistivity, conductivity and dielectric constant measurement using the I-V and C-V meter, the resistivity of Zn NiO samples (x = 1, 3 and 5%) was increased by the progressive level of holding time 2, 4 and 8 hours, while the conductivity was decreased. The increasing of resistivity indicated by the difference between the Zn2+ and Ni2+ ions radius that led to internal stress on ZnO lattice system and resulted the grain boundaries defects. Dielectric constant was increasing by the progressive level of holding time since the Ni2* occupy the center position of Zn, which leads to a permanent electric dipole area and showed the dielectric behavior. Another aspect of dielectric behavior present is due to the vacancy of oxygen that produced the nonuniformity of grain boundaries. This nonuniformity resulting the polarized electrons. Polarization mechanism on dielectric field generates the electric charge storage. The result of VSM characterization indicated the ferromagnetic properties of ZnNiO sample. By the 3%. at Ni concentration with 2- and 8-hours holding time, the coercivity (Hc) and Ms values were decrease, while the remanence progressively increase due to the impurity presence of Nickel Zinc Oxide.