ABSTRAK
Fabrikasi nanopartikel kobalt ferrit hasil ko-presipitasi dilanjutkan dengan two step annealing telah dilakukan. Two step annealing dilakukan pada keadaan atmosfir. Hasil karakterisasi FTIR menunjukkan hidroksida sisa sintesis yang menghilang dengan semakin tingginya suhu sintesis yang diterapkan, dan perlakuan two step annealing hanya menggeser level transmitansi. Hasil analisis struktur kristal memperlihatkan sampel yang terbentuk adalah kubus FCC. CoFe2O4 dengan puncak spektrum berada pada sudut 2? = 35,7? bersesuaian dengan bidang indeks Miller (hkl) = 311. Modifikasi suhu sintesis dan, two step annealing telah berhasil memberikan perubahan ukuran kristalit. Variasi konsentrasi NaOH tidak secara langsung berpengaruh pada ukuran kristalit. Hasil analisis vibrating sample magnetometer menegaskan medan koersif HC=550 Oe (sintesis suhu 95?C) dan Hc=265 Oe (sintesis suhu ruang).
Kata kunci: Kobalt Ferrit, Ko-presipitasi, Kristal, Koersifitas
ABSTRACT
Fabrication of cobalt ferit nanoparticel resulted by the ko-precipitation followed by two step annealing has been done. Two step annealing was performed at atmosphere condition. FTIR characterization results shows a synthesis of residual hydroxide disappeared due to increasingly high temperature synthesis is applied, and the treatment of the two step annealing that shift the transmittance level.  Result of crystal structure analysis shows that sample formed is the cube of the FCC. Crystal structure analysis of the results shows a sample that is formed is the cube of the FCC. CoFe2O4 with spectral peak at an angle 2? = 35,7? Miller indices correspondingto to the plane (hkl) = 311. Modification of temperature synthesis and two step annealing have managed to deliver the changes the size of the crystallites. Variations of concentration does not directly affected the size of the crystallites. The results of the analysis of vibrating sample magnetometer confirmed the coercive field HC = 550 Oe (synthesis of temperature 95 ?C) and Hc = 265 Oe (synthesis of room temperature).
Keywords: Cobalt Ferrite, Co-precipitation, Crystal, Coersivity