Karakterisasi Barium Heksaferit (BaFe12O19)dan Nikel Oksida (NiO) sebagai Penyerap Gelombang Mikro

Abstract

The synthesis of Barium Hexaferrite (BaFe12O19) and Nickel Oxide (NiO) composites using the Mechanical Alloying method as microwave absorbers has been successfully carried out. The wet mixing process of BaFe12O19/NiO was conducted using High Energy Milling at a speed of 450 rpm for 1 hour with ethanol as the medium for the Barium Hexaferrite (BaFe12O19) and Nickel Oxide (NiO) powders, with variations in NiO composition (%wt) of 10%, 15%, and 20%. Each sample was then dried using an oven at a temperature of 100°C for 4 hours. Subsequent heat treatment with a calcination step was performed on each sample at 1000°C for 2 hours. After the calcination process was completed, the samples were ground and sieved using a 100- mesh sieve. Characterization of the samples was carried out using X-Ray Diffraction (XRD) to determine the formed phases, highest peaks, and crystal structure. Scanning Electron Microscope and Energy Dispersive X-ray (SEM-EDX) were used to analyze the structure and morphology formed in each sample, and the Vibrating Network Analyzer (VNA) was used to evaluate the microwave absorption performance of BaFe12O19/NiO with NiO composition variations of 10%, 15%, and 20%. The XRD results identified two crystal phases: hexagonal magnetoplumbite and cubic crystal with a Miller index of 202. SEM-EDX revealed inhomogeneity in BaFe12O19/NiO at 15% and 20% variations. VNA analysis showed that the microwave absorption performance of BaFe12O19/NiO increased with higher NiO composition in the composite. The BaFe12O19/NiO composite with 20% NiO achieved a maximum Reflection Loss value of-11.739 dB at a frequency of 8.18 GHz.