A smart photodynamic ionic liquid nanogel fiber-based actuator with efficient photothermal conversion and self-cleaning achieved by supramolecular assembly

Abstract

Advanced intelligent actuators and efficient interfacial evaporator materials have been attracting significant attention from researchers and also remain a huge challenge. Inspired by giant pillars in nature, we report a smart self-cleaning photodynamic nanogel actuator and efficient photothermal energy conversion fiber-based composite (KF-PVA@AzoPc1), which is based on the supramolecular assembly of nanogels from the disk-like phthalocyanine–azobenzene ionic liquid (AzoPc1). The self-assembled nanogels exhibit smart actuation, photoresponsive, supramolecular photoliquefaction and nanodomain nematic liquid crystal properties. Interestingly, the photodynamic actuator can intelligently move and deform under either UV or IR light, respectively. The photodynamic nanogel hollow fiber actuator KF-PVA@AzoPc1 acts as a smart photothermal energy evaporator, whose temperature can reach up to 73.6 °C, with a water evaporation rate of 6.35 kg m⁻² h⁻¹ under solar irradiation. KF-PVA@AzoPc1 demonstrates unique UV-IR-responsive thermal cycling, excellent light-driven behavior, and efficient photothermal self-cleaning antibacterial performance. This work establishes a smart micro-/nanosystem actuator platform based on ionic liquid supramolecular assembly, which has potential applications as an advanced intelligent actuator and in smart self-cleaning evaporation systems with integrated solar harvesting, energy storage, and pathogen eradication capabilities.