Dual-Energy Harvesting Using Recycled Cat Fur and α-Fe₂O₃ Nanoparticles for Self-Powered Photodetection and Human-Pet Health Care

A sustainable method for recycling cat fur waste into a self-powered photosensing system has been developed in this study, addressing the current global energy shortage and environmental crisis. We have successfully initiated the systematic reuse of problematic cat fur waste as a positive tribo-layer in a photoinduced triboelectric nanogenerator (TENG) device; this was achieved by developing a tribo-pair supported by hematite nanoparticles (α-Fe<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>O<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> NPs), creating an optically active negative tribo-layer using an economical, simple, and eco-friendly chemical method. In this study, we demonstrated that the photoinduced TENG output signal was intensified by approximately 1.2–1.4 times during friction between a hematite nanoparticles film and a chemically processed cat fur waste film. This intensification was achieved by utilizing the considerable positive polarity of cat fur, along with the photosensitivity and electron-trapping ability of the hematite nanoparticles, under full-spectrum conditions. This demonstrates a dual-energy harvesting module that simultaneously harvests vibrational and solar energy from the surrounding environment. The output signals from the photoinduced TENG exhibit significant alterations when illuminated with light of varying intensity and wavelength values; this results in remarkable photo response characteristics, such as an appreciable responsivity of 324.68 V W<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> and a broadband photodetection capability covering the near-ultraviolet (UV), visible, and near-infrared (IR) regions. Apart from developing a novel approach to self-powered photodetection, this study also demonstrates a promising method to integrate this green energy resource with self-powered human-pet health protection systems. Additionally, this work develops a circular bioeconomy as part of an Environmental, Social, and Governance (ESG) strategy.