We present herein a modified cold s

We present herein a modified cold sintering process for BaTiO3 ceramics that exploits a surface coating at the particle surface. Bulk densities up to ∼96% theoretical are realized by cold sintering at 220℃ and 500 MPa. The surface coating greatly enhances the ceramic density, mainly because it facilitates the dissolution-precipitation process during cold sintering. Ba vacancies form at the surface of the coated powders, so Ba(OH)2 solution is used to compensate Ba ions in the as-cold-sintered ceramics, which increases the dielectric permittivity. Post-annealing at 700 and 900℃ increases the relative density to 97%, and the resulting relative dielectric permittivities are 810 and 1550, respectively, at room temperature and 1 kHz. This technique may also be extended to materials with very small, incongruent solubility in water or volatile solutions that use the cold sintering process.