Published online by Cambridge University Press: 21 February 2011
The aqueous deposition of calcium oxalate onto colloidal oxides has beenstudied as a model system for understanding heterogeneous nucleationprocesses of importance in biomimetic synthesis of ceramic thin films.Calcium oxalate nucleation has been monitored by measuring induction timesfor nucleation using Constant Composition techniques and by measuringnucleation densities on extended oxide surfaces using an atomic forcemicroscope. Results show that the dependence of calcium oxalate nucleationon solution supersaturation fits the functional form predicted by classicalnucleation theories. Anionic surfaces appear to promote nucleation betterthan cationic surfaces, lowering the effective energy barrier toheterogeneous nucleation.