Part I: A Study of the Underlying Factor(s) Effecting the Change of Point of Zero Charge With Decreasing Particle Size

The general consensus in multiple fields is that changes in the average primary particle size of metal-oxides and -hydroxides affects their Point of Zero Charge (PZC). In the course of this study on anatase titania, a method was developed to minimize the effect of all known variables affecting the material’s pHPZC, save particle size. This led to the discovery of two regions for point of zero charge. Above the average spherical particle diameter ≅ 29, (Region I) pHPZC remains constant demonstrating particle size has no effect on this value . Below a diameter ≅ 29 nm (Region II), pHPZC values decrease in an almost linear manner.