Synthesis and piezoelectric properties of Li, Ca and Mn-codoped BaTiO ₃ by a solvothermal approach

3 at.% Li-doped (Ba_1-xCa_x)(Ti_1-yMn _y)O₃ particles with the Ca²⁺ mole fraction, x, of 0-0.09 and Mn mole fraction, y, of 0 and 0.0005 were synthesized by a solvothermal approach at 200°C. The products consisted of nanoparticles of 50-100 nm in diameter, and did not change very much depending on the amount of Li, Ca and Mn-codoping. The change in relative dielectric constant, Δ_r, in around room temperature decreased by doping Ca ²⁺, and the lowest Δ_r (4.51%) could be realized at x value of 0.03. The mechanical quality factor, Q_m, of 3 at.% Li-doped (Ba_0.97Ca_0.03)(Ti_0.9995Mn_0.0005) O₃ increased to 521, and Δ_r decreased to 1.72%, while the piezoelectric constant, d₃₃ (234pC/N), and electromechanical coupling factor, k_p (40.0%), did not change very much compared with 3 at.% Li-doped BaTiO₃.