Preparation and Characterization of Raspberry-Like TiO<sub>2</sub>/Cu Composite Particles

Raspberry-like TiO2/Cu composite particles were prepared under mild conditions (75°C and ambient pressure) by hydrolysis of Ti(OBu)4 in acidic aqueous solution and subsequent reflux in the presence of micron size Cu powders. A 3-level and 4-factor design was employed to evaluate the effect of the main parameters on the coating quality. TiO2 particles of approximate 100nm in size were found coating on the surfaces of Cu powders to form raspberry-like structure. Ti and Cu element mainly existed on the composite particle surface as the chemical state of Ti4+ and Cu2+. TG-DTA analysis showed the TiO2 coating increased the thermal stability of Cu particles. The composite particles began oxidizing at 400°C while pure copper particles oxidized at 200°C.