Interfacial Kinetics Through the Lens of Solution Chemistry: Hydrolytic Processes at Oxide Mineral Surfaces

Mineral dissolution and growth can be understood, in part, by drawing analogies with reactions where a dissolved metal exchanges ligands in solution. The rates of dissolution are generally controlled by slow hydrolytic dissociation of surface complexes at monomolecular steps on the mineral surfaces. Rates of oxygen exchange around metals in dissolved metal-ligand complexes also involve hydrolysis. In both environments these rates depend on association to protons, or certain ligands, in the inner-coordination sphere of the metal. An enormous literature of useful data describes microscopic acid-base chemistry of oxide oligomers and the molecular controls on their condensation and dissociation. This literature may be extraordinarily useful in understanding oxide interfacial chemistry. It is presently unknown whether rate coefficients from the solution state can be directly transferred to surface reactions, but useful comparisons can be made to identify reactivity trends.