Bi3TeBO9: A Borate Piezoelectric Crystal with a High Piezoelectric Coefficient

The borate piezoelectric crystal Bi 3 TeBO 9 (BTBO) was successfully grown by the top-seeded solution growth (TSSG) method. Frequency-dependent polarization measurements reveal that BTBO is not ferroelectric. Under the combined effects of high dielectric (ε 33 = 62.60) and elastic constants ( s 33 = 15.33 pm 2 /N), BTBO exhibits a high longitudinal piezoelectric coefficient d 33 of 24.4 pC/N, which is larger than that of LiNbO 3 (LN) and second only to α-BiB 3 O 6 (BIBO) among known borate crystals. First-principles calculations and structural analysis indicate that the piezoelectric properties of BTBO mainly originate from the strong lattice polarization induced by the [BiO 6 ] and [TeO 6 ] groups. Additionally, the temperature dependence of the piezoelectric coefficient and electrical resistivity was also measured. The results suggest that BTBO is a potential candidate for piezoelectric applications with its high piezoelectric coefficient, resistivity, and piezoelectric temperture stability.