Effective interfacial energy band engineering strategy toward high-performance triboelectric nanogenerator

Provided that electron transition ascribed to overlapping electron dominates the mechanism of contact electrification of triboelectric nanogenerators (TENGs), the electron transfer process occurs due to the built-up electric field between the triboelectrification surface and bottom electrode. In this work, we embed a solution-processed high-permittivity electron blocking layer (HPEBL) of LaZrO into the classical contact-separation mode TENG to build an energy barrier (ΔE > 1.3 eV) between ITO and PDMS, which could effectively block the transportation of electrons towards the bottom electrode. The surface potential decline rate of PDMS is obviously suppressed, extending the half-charge decay time by ∼3.1 times. A La_0.1Zr_0.9O_x HPEBL based TENG (H-TENG) demonstrates the electrical outputs with 215 V, 96.3 mA m⁻² and 243.3 μC/m⁻². Under the external load of 100 MΩ, the average gravimetric/volumetric power density and energy conversion efficiency can be calculated to be 59.34 μW g⁻¹, 152.5 μW cm⁻³ and 39.2%, respectively. Furthermore, the dielectric behaviors of LaZrO thin films are investigated by metal–insulator-metal (MIM) devices. The Poole-Frenkel (PF) emission is found to dominate the leakage mechanism of LaZrO during operation. Consequently, increasing the relative permittivity and reducing the trap density could be indicated as the optimization orientation of HPEBL.