Crystalline water induced nonpolar‐to‐polar transition and high piezoelectric response in lamivudine hydrate crystal.

Electromechanically converted piezoelectric materials have great applications in actuators, sensors, and energy harvesters. Organic piezoelectric materials are environmentally friendly, easy to prepare, and have a low molecular mass compared to conventional inorganic piezoelectric materials. Here, we present an organic hydrogen bonding piezoelectric material, lamivudine hydrate, which crystallized in the P21 space group at room temperature and exhibits a decent d33 value of 21 pC N−1. This value is comparable to that of the commercial piezoelectric material, Tri‐Glycine Sulfate (TGS, d33=22 pC N−1). Moreover, lamivudine hydrate possesses a superior g33 value of 826×10−3 V m N−1, which is much higher than that of commercial TGS and most of the piezoelectric ceramics. While the lamivudine crystal was refined in the P43212 space group, showing no piezoelectric activity. The presence of crystalline water plays a crucial role in establishing its polar structure and achieving high piezoelectric properties of lamivudine hydrate crystal. The decent d33 and g33 values make it a promising candidate for advanced materials in high‐performance piezoelectric sensors, particularly in applications involving flexible, wearable, and biomechanical devices. [ABSTRACT FROM AUTHOR]