Dielectric particles having passivated surfaces and methods of forming same

The invention provides dielectric (e.g., barium titanate-based) particles having passivated surfaces. The surfaces may be passivated, for example, using methods that limit the dissolution of divalent metals (e.g., barium) from the particle surfaces in subsequent processing steps. In some methods, the surfaces are passivated by washing the particles to form a divalent metal-depleted surface region. In other methods, the particles may be coated with a divalent metal insoluble compound or a divalent metal free compound. Advantageously, the surface passivated particles may be uniformly dispersed to form dispersions that are stable for long periods of time and may be further processed to form articles having particles uniformly dispersed therein. The particles are particularly suitable in the formation of polymer/dielectric composites that may be used in embedded capacitor applications.