Electrospun PAN Membrane Loaded with AgInP ₂ Se ₆ Nanosheets for Triboelectric Energy Harvesting

Abstract To address the gap in the application of mixed‐metal phosphorus trichalcogenides (M ^I M ^III P ₂ X ₆ ) in energy harvesting systems, this work investigates the incorporation of exfoliated silver‐indium‐phosphorus‐selenide (AgInP ₂ Se ₆ ) into electrospun polyacrylonitrile (PAN) fibers for triboelectric nanogenerator (TENG) applications. This research marks the first‐time exfoliation of AgInP ₂ Se ₆ (exf‐AgInP ₂ Se ₆ ) and its integration into a polymer matrix, resulting in the first demonstration of a M ^I M ^III P ₂ X ₆ ‐based polymer composite processed into a flexible nanogenerator via electrospinning. Comprehensive structural and morphological characterization confirms the successful incorporation of exfoliated AgInP ₂ Se ₆ within the PAN fiber without compromising the crystallinity or fiber integrity. The exf‐AgInP ₂ Se ₆ /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‐AgInP ₂ Se ₆ as a functional triboelectric material.