Advancing Humidity-Resistant Triboelectric Nanogenerators Through MoS2-Encapsulated SiO2 Nanoparticles for Self-Powered Gas Sensing Applications

Abstract

In this study, the humidity-resistant triboelectric nanogenerators (TENGs) utilizing MoS2-encapsulated SiO2 nanoparticles (NPs), aimed at enhancing self-powered gas sensing applications, are reported. The core-shell structure, featuring a thin MoS2 layer uniformly grown on SiO2, addresses common humidity-induced performance degradation. The growth mechanism involves the decomposition and sulfidation of molybdenum species, with MoS2 selectively nucleating on SiO2 to form a stable, hydrophobic shell. This MoS2 layer effectively shields the SiO2 interface from water molecule penetration, thus stabilizing charge density and significantly reducing charge decay, even under high humidity conditions. TENGs constructed with these core-shell NPs exhibit high triboelectric charge density and exceptional durability, retaining more than 70% output over 25 h at 99% relative humidity (RH). Furthermore, the fabricated TENG reliably powers a gas sensor array, enabling accurate gas detection in extreme humidity. This work demonstrates the potential of MoS2-encapsulated SiO2 TENGs as robust, self-powered energy solutions for environmental monitoring and wearable devices in challenging humidity conditions.