Electrospun PAN Membrane Loaded with AgInP₂Se₆ Nanosheets for Triboelectric Energy Harvesting

To address the gap in the application of mixed-metal phosphorus trichalcogenides (M^IM^IIIP₂X₆) in energy harvesting systems, this work investigates the incorporation of exfoliated silver-indium-phosphorus-selenide (AgInP₂Se₆) into electrospun polyacrylonitrile (PAN) fibers for triboelectric nanogenerator (TENG) applications. This research marks the first-time exfoliation of AgInP₂Se₆ (exf-AgInP₂Se₆) and its integration into a polymer matrix, resulting in the first demonstration of a M^IM^IIIP₂X₆-based polymer composite processed into a flexible nanogenerator via electrospinning. Comprehensive structural and morphological characterization confirms the successful incorporation of exfoliated AgInP₂Se₆ within the PAN fiber without compromising the crystallinity or fiber integrity. The exf-AgInP₂Se₆/PAN membrane is tested as a TENG device, operating in contact-separation mode, and demonstrates excellent output performance and stability under mechanical deformation. The device exhibits competitive electrical performance, reaching a peak power density of 480 mW·m^-2 at 1 GΩ load, and remains functional under mechanical deformation. Additionally, it exhibits a strong and humidity-dependent electrical response, with peak performance at low humidity (20% relative humidity (RH)) and complete recovery of output after exposure to high humidity (70% RH), enabling potential applications as a self-powered humidity sensor. This study expands the range of two-dimensional (2D) materials for energy harvesting by demonstrating exf-AgInP₂Se₆ as a functional triboelectric material.