Recently, piezoelectric/triboelectric nanogenerators based on piezoelectric composite materials have been intensively studied to achieve high electrical output performance. In this work, flexible BaTiO₃ (BT)/PDMS nanocomposite films with various sizes and concentrations were fabricated and used as the nanogenerators. The influence of dielectric properties on the electrical output of nanogenerators was studied as well as the structure of the composites. The dielectric constant increased from 6.5 to 8 with the concentration of BT nanoparticles and decreased with the frequency from 10² to 10⁶ Hz. Furthermore, the dielectric constant showed 11% decrease with the temperature range from 30 to 180 ℃. It was found that the concentration of BT nanoparticles has promoted the electrical output of nanogenerators. The output voltage and current are all enhanced with the BT nanoparticles, which reached 200 V and 0.24 μA in TENG with 40 wt% BT nanoparticles, respectively. The selected device exhibited the power of 0.16 mW and employed to demonstrate its ability to power wearable/portable electronics by lighting the LEDs.

Rare earth (RE = La³⁺, Sm³⁺, Pr³⁺) ion doped Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ (RE-PMN-PT) ferroelectric thin films with compositions near the morphotropic phase boundary were grown on the Pt/TiO₂/SiO₂/Si(100) substrate using sol-gel/spin coating method. The phase structure, electrical properties, and photoluminescence performance of thin films were investigated systematically. The highly (100)-preferred orientation was obtained in pure perovskite Sm-PMN-0.30PT thin films with an average grain size of 131 nm. After 2.5% Sm³⁺ doping, the PMN-0.30PT thin films exhibited a triple enhancement of dielectric permittivity with a maximum value of 3500 at 1 kHz, a low dielectric loss of 1.3%, and high remanent polarization of 17.5 μC/cm² at room temperature. In visible light and near-infrared band, the transmittance rate increased with PT content and showed the highest value of 85% in 2.5%Sm-PMN-0.31PT. In addition, the films presented strong red-orange emission at 599 nm, which was sensitively in temperature range of 248-273 K corresponding to the rhombohedral to monoclinic phase transition temperature.