Sintesis dan Karakteristik Fasa Cu-Cr-O Menggunakan Pelarut H2so4 dan HNO3 dengan Metode SOL-GEL

Abstract

Cu-Cr-O material was a material that hat a delafossite structure and potentially hat good thermoelectric properties. In this study, the Cu-Cr-O material has been synthesized using the sol-gel method using H₂SO4 and HNO3 solvents, with a Cu:Cr mole ratio (2:1 and 1:1), and the addition of urea, through a 1000°C sintering process for 3 hours. The materials used as precursors are Copper (II) nitrate trihydrate (Cu(NO3): 3H2O), Chromium (III) oxide (Cr:O) and Urea (CO(NH2)2) according to stoichiometric calculations for each sample. The precursor mixing process starts from Cu(NO3): 3H2O), mixed with (CO(NH2)2) then the precursor material (Cr2O3) is dissolved with H:SO-HNO; accordance with the provisions and stoichiometric calculations. Then it enters the process of making the gel, then it is calcined and sintered, then it is crushed and the sample is compacted. The characterization has been used XRD characterization to analyze phase formation, SEM characterization to analyze the microstructure of each sample. From the results of research that has been done, XRD characterization results show the effect of using H₂SO4 and HNO3 as solvents, and the addition of Urea (CO(NH2)2) to each sample and the addition of Urea 2 times to the 4th sample, where the phase formed is the CuCr2O4 phase, with Cr2O3 impurities, and CuO. Excessive use of urea causes the formation of the CuCr2O4 phase.