Enabling Charge Trapping with Quasi-Magnetization through Transition Metal Ion-Chelated Mesoporous Silica Particles for Wearable Antibacterial Self-Powering Sensors

Abstract

Wearable self-powering sensors based on triboelectric nanogenerators (TENGs) emerging as a promising strategy for a wide range of applications, such as self-powering and energy-harvesting systems, are widely used in healthcare and displacement current are utilized as the driving force. Although the TENG theory is rooted in the displacement current equation proposed by Maxwell, the magnetic field created by this current is often overlooked in TENG research. In this work, an effective charge-trapping method based on the magnetization current induced by transition metal ion chelation is reported. The experimental results, along with a theoretical analysis of the Maxwell equation and a discussion of the charge-trapping mechanism, demonstrate that magnetic materials provide enhanced charge-trapping performance. Transition metal ions chelated to mesoporous silica particles (MSPs) can slightly assign weak paramagnetic properties owing to the formation of ligand complexes. As a result, they can generate a feeble quasi-magnetization current during the TENG cycle, which enhances the surface charge density of the Co-MSPs-based polyvinyl alcohol TENG (PVA-TENG) by 68%. In addition, it is confirmed that the MSPs chelated with transition metal ions exhibit antibacterial properties, thereby providing promising synergistic effects from the perspective of application as a wearable TENG-based antibacterial sensor system.