High‐Current‐Density and Photo‐Enhanced Direct‐Current Triboelectric Nanogenerator Based on Lead‐Free Air‐Stable Sb ³⁺ doped CsBi ₃ I

ABSTRACT

With the rapid development of distributed sensor systems, direct‐current triboelectric nanogenerators (DC‐TENGs) based on tribovoltaic effects have attracted wide attention. However, the development of efficient semiconductor materials for enhanced output remains challenging. Herein, air‐stable Sb ³⁺ doped CsBi ₃ I ₁₀ films were synthesized, and DC‐TENG devices based on Al/CsBi _2.7 Sb _0.3 I ₁₀ dynamic Schottky junction were then developed for harvesting mechanical and solar energy. Among a series of Sb ³⁺ doping concentrations, the CsBi _2.7 Sb _0.3 I ₁₀ film exhibits the narrowest FWHM (Full Width at Half Maximum) value and the best crystallinity. Being ascribed to more suitable energy‐level alignment, reduced trap states, and especially increased dielectric constant, the optimized Al/CsBi _2.7 Sb _0.3 I ₁₀ DC‐TENG delivers a short‐circuit current density of 31.4 A m ⁻² and an open‐circuit voltage of 4.3 V under dark conditions, with respective increase of approximately 29.8% and 26.5% compared with the Al/CsBi ₃ I ₁₀ DC‐TENG. Under simulated sunlight illumination, the output further increases to 44.1 A m ⁻² and 7.5 V, which is attributed to the contribution of photogenerated carriers during the dynamic contact process. Moreover, the device maintains stable output performance after being placed in ambient air for 49 days. This work provides a feasible strategy for developing lead‐free perovskite semiconductor‐based DC‐TENGs with enhanced electrical output and multi‐energy harvesting capability.