Self-Powered Analytical Strips Based on Evaporation-Driven Generator for ESDD Detection of Insulator in Electrical Equipment

Harvesting energy from natural water via an evaporation-driven hydrovoltaic device (EHD) has attracted tremendous interest, and it also offers exceptional potential for application in self-powered sensing owing to its independent operation and stability. Here, we fabricated an analytical strip by vacuum filtering single-walled carbon nanotubes (SWCNTs) into cellulose paper for highly sensitive salinity detection in water solution. The role of electrode structure, water solution ions, and temperature on the EHD response was systematically investigated. Specifically, this type of analytical strip has a specific continuous load capacity and produces a consistent voltage output of ~0.55 V. Furthermore, a self-powered equivalent salt deposit density (ESDD) sensor based on EHD was adopted for insulator contamination detection in electrical equipment, demonstrating superior sensitivity, stability, and anti-interference ability. This work broadens the EHD-based self-powered sensor and provides a quick monitoring strategy for the operational state of insulators in the electrical equipment.