Abstract
A new homogeneous precipitation was carried out utilizing the mixed solutions of polyaminocarboxylate complexes of transition metal (Co2+, Fe2+, Ni2+ and Zn2+) and phosphate (NH4H2PO4 or NaH2PO4) in order to prepare monodispersed crystalline particles. Monodispersed spherical particle of CoHPO4·3H2O was formed in the mixed solutions of 0.05M Co(edta)2- and 0.15M NaH2PO4 at pH6.5 and 200°C for 4h and rod-like CoHPO4·1.5H2O was formed at pH4 and 200°C for 2h. Furthermore similar spherical Ni3(PO4)2·8H2O was formed in the mixed solutions of Ni(edta)2- and NH4H2PO4 at pH7 and 250°C for 2h. Fibrous Zn2(OH)PO4 was formed in the mixed solutions of Zn(nta)22- and NH4H2PO4 at pH4 and 250°C for 2h. The particle morphology could be controlled by adjusting a kind of metal polyaminocarboxylate, temperature and pH.
