Fabrication and properties of BaTiO3 ceramics via digital light processing for piezoelectric energy harvesters

Piezoelectric ceramics are vital components in electronic devices. These components with designed complicated structures are difficult to be fabricated using traditional methods due to their high brittleness and hardness. Additive manufacturing technologies offer new opportunities for the preparation of piezoelectric ceramics. Herein, we prepared high-performance BaTiO3 ceramics by digital light processing. The slurry with 1.5 wt % dispersant content showed favourable dispersion effect and stability. The optimum photoinitiator of 3 wt % and applied energy dose of 160 mJ/cm2 could provide a sufficient interlayer combination. After a sintering process, sintered BaTiO3 ceramics kept a single perovskite tetragonal structure and the relative density reached 95.4%, which could be comparable to that of BaTiO3 ceramics prepared by dry pressing. The printed BaTiO3 ceramics exhibited favorable dielectric and piezoelectric properties (ɛr = 1543, tan δ = 0.0185, d33 = 180 pC/N, g33 = 1.32 × 10−2 Vm/N and FOMoff = 1.28 × 10−10 m2/N). Furthermore, some samples with designed complicated structures were fabricated to evaluate the performance of piezoelectric energy harvesting, and an open circuit voltage and short circuit current of ∼5.5 mV and ∼5.2 pA were obtained. These results indicate that digital light processing is a promising approach to fabricate piezoelectric energy-harvesting ceramics with high geometrical flexibility.