Differential Ion Solubility

The preferential solubilization of ions from the surface of a sparingly soluble crystalline material represents one of the most common and earliest recognized mechanisms for the development of electrical charges on solid surfaces. A widely encountered example of such an effect is in the silver halide colloids (incorrectly, but commonly referred to in the business as emulsions ) used in photographic products. 

---

Differential ion solubility, as in the case of the well-studied sy.stem of dispersed Agl particles (fiO). 

FIGURE 5.1. The principle sources of surface charge in solids include (a) differential ion solubility phenomena, (h) direct ionization of surface groups, (c) isomorphous substitution of ions from solution, and (d) speciflc-ion adsorption from the solution phase (e) anisotropic crystal lattice structures. 

Figure 10.11 Sources of surface charge in colloids, (a) Differential ion solubility (b) direct ionization of surface groups (c) isomorphous substitution (d) specific ion adsorption and (e) anisotropic crystals. Adapted from Myers (1999), with permission from John Wiley Sons, Ltd...

---