Spiral Electrodes‐Enhanced Triboelectrification‐Induced Electroluminescence in Nanocellulose Composites for Self‐Powered Visualized Acoustic Sensing

Triboelectrification‐induced electroluminescence (TIEL) as an emerging motion‐activated luminescence has garnered substantial interest for its potential in visualized sensing applications. However, the current practice of TIEL predominantly relies on non‐degradable synthetic polymers that severely limit their sustainability. Herein, a nanocellulose‐based TIEL composite is first developed by incorporating ZnS:Cu into a chitosan/bacterial cellulose matrix, which exhibits remarkable multifunctional features including high‐brightness (28 μW cm −2 ), ultra‐low density (0.6 g cm −3 ), environmental resilience (100°C; 70% RH), controlled biodegradability, and exceptional mechanical flexibility. Leveraging this material, a modular self‐powered visualized acoustic sensor (SP‐VAS) is designed through the integration of complementary Archimedean spiral electrodes, which can convert acoustic waves into TIEL signals without any external power supply. The optimized fringe field from the electrodes enhances acoustic‐to‐TIEL conversion efficiency, yielding a sevenfold increase in TIEL intensity. The resultant SP‐VAS is demonstrated as applicable for sound recognition and interaction. With the use of deep‐learning algorithms, five different instrument sounds were recognized with an accuracy of up to 99.36%. Furthermore, the voice‐TIEL activation of desk lamp control was achieved by combining the SP‐VAS with a microcontroller unit (MCU)‐assisted operation. This work establishes a novel strategy for developing environmentally friendly and high‐performance TIEL materials while advancing acoustic‐optic transduction technology, which shows transformative potential for applications in next‐generation intelligent robotics, smart homes, and autonomous vehicles.