Study On Preparation Of Co₃O₄with Microwave And Ultrasonic By Synthesizing Under Liquid Phrase

Cobalt oxide catalyst are widely used in battery cathode material synthetic materials, batterycathode materials, super-capacitors, carbide, semiconductor ceramics, paint additives, enamel andceramic pigments, petroleum refining catalysts. With the improvement of the application scale,we study on the particle size and make the performance better. Co(NO3)2·6H2O as raw material inthis paper, effects of microwave and ultrasonic synergistic effect on by homogeneousprecipitation method for the synthesis of Co3O4precursor morphology, no need to add anymodifiers can prepare nanometer whisker Co3O4precursor and then in the furnace for roastingultrafine Co3O4powder. Study on the precipitating agents, reaction models, reactantconcentrations, molar ratio, temperature of reaction system, time of reaction system, ultrasonicpower, aging time on Co3O4powder particle size and particle size distribution and so on. Used asingle factor experiment, I pursued the reaction conditions for making the small D50, uniformparticle size distribution, whisker Co3O4and Co3O4. The using of SEM, XRD,FT-IR,TG-DTGanalysis the Co3O4powder，the detection of Co3O4powder, Co3O4powder morphology, particlesize, purity and composition of matter.Compared with Na2CO3, NaHCO3, H2C2O4, CO(NH2)2as a precipitating agent, was obtainedwhisker morphology, nanometer size, a small particle size, narrow particle size distribution ofCo3O4precursor particles. Examined a single microwave radiation heating, constant temperaturewater bath heating and microwave and ultrasonic, microwave and ultrasonic is the fastest. Effectsof microwave and ultrasonic synergistic effect on by homogeneous precipitation method for thesynthesis of Co3O4precursor morphology, CO(NH2)2and Co(NO3)2mass ratio were3:1,[Co2+]concentration was1.0mol L-1, temperature of80℃, aging time was3h, microwave power700W, ultrasonic power1200W(ultrasonic model was2:1), aging time0h.With XRD analysis, there are two kinds of precursors, the one is Co2(OH)2CO3, the other isCoC2O4. TG-DTG analysis by300℃~820℃after roasting of the precursor can get Co3O4.Decomposition temperature of700~800℃, holding time3h are reasonable. The FT-IR and XRDanalysis showed that the product was Co3O4and the Co3O4was full crystal matrix, high purity,free of impurities cubic phase at the temperature of800℃, holding3h, but the performanceturned into spherical or coral.Used the scherrer formula calculated Co3O4, the average grain sizewas30~40nm.The experiment also showed, compared with the ordinary decomposition, microwave dryingand microwave decomposition may produce the whisker or fibras or nane spherical Co3O4. Dueto the limitation of time and experimental conditions, the study on heredity and variation ofprecursor and product under the microwave is on the further study.