Chitosan‐Loaded Lead‐Free Sodium Bismuth Titanate Composite Flexible Triboelectric Nanogenerator for Energy Harvesting, Biomechanical Sensing, and Smart‐Path Touch‐Lighting for Safe Walking Applications

Why It Matters

The breakthrough offers an eco‑friendly, high‑output energy harvester that can power distributed IoT sensors and safety lighting without external power, accelerating adoption of self‑sustaining smart infrastructure.

Key Takeaways

• Lead-free NBT/chitosan composite boosts dielectric constant
• Flexible TENG delivers 162.5 V, 4.1 µA output
• Power density reaches 1.34 W/m²
• Powers Arduino-controlled pathway lighting in real time
• Demonstrates viable self-powered biomechanical sensing

Pulse Analysis

The rapid depletion of fossil fuels and rising carbon emissions have intensified research into alternative power sources, positioning triboelectric nanogenerators (TENGs) at the forefront of wearable and ambient energy harvesting. Traditional TENGs often rely on toxic or brittle materials, limiting their scalability for outdoor or biomedical use. Recent advances focus on flexible, environmentally benign polymers combined with high‑dielectric ceramics to improve charge transfer while maintaining mechanical compliance. In this context, lead‑free sodium bismuth titanate (NBT) emerges as a promising ferroelectric filler that can be processed alongside biocompatible polymers such as chitosan.

The NBT/chitosan composite film reported in the study leverages the high permittivity of NBT particles to amplify the triboelectric charge density across the PDMS interface. By embedding NBT within a chitosan matrix, the researchers achieved a peak output of 162.5 V and 4.1 µA, translating to a power density of 1.34 W·m⁻²—metrics that surpass many conventional polymer‑only TENGs. This performance gain stems from reduced charge recombination and enhanced electric field concentration, demonstrating that lead‑free ferroelectric ceramics can bridge the gap between output efficiency and environmental safety.

Beyond raw performance, the device’s integration with an Arduino UNO to trigger pathway lighting illustrates a practical, self‑powered IoT application. Real‑time illumination activated by footfall offers a low‑cost solution for pedestrian safety in parks, campuses, and smart cities, while the same platform can support biomechanical sensing for health monitoring. The modular nature of the composite TENG enables scaling to larger surfaces or embedding into textiles, opening avenues for distributed sensor networks that draw power directly from human motion. As regulatory pressure mounts on hazardous materials, such lead‑free, flexible generators are poised to accelerate the deployment of autonomous, sustainable smart‑infrastructure.