Ag Nanoparticles Deposited onto BaTiO₃ Aerogel for Highly Efficient Photodegradation

Given the increasingly severe environmental problems caused by water pollution, the degradation of organic dyes can be effectively achieved through the utilization of photocatalysis. In this work, metal alkoxides and a combination of alcohol/hydrophobic solvents are employed to prepare BaTiO₃ aerogels via a liquid-phase and template-free synthetic route. The preparation process of the aerogels solely entails facile agitation and supercritical drying, eliminating the need for additional heat treatment. The binary solvent of ethanol and toluene is identified as the optimal choice, resulting in a significantly enhanced surface area (up to 223 m²/g) and an abundant pore structure of BaTiO₃ aerogels compared to that of the BaTiO₃ nanoparticles. Thus, the removal efficiency of the BaTiO₃ aerogel sample for MO is nearly twice as high as that of the BaTiO₃ nanoparticles sample. Noble metal Ag nanoparticles' deposition onto the BaTiO₃ aerogel surface is further achieved via the photochemical deposition method, which enhances the capture of photogenerated electrons, thereby ensuring an elevated level of photocatalytic efficiency. As a result, Ag nanoparticles deposited on BaTiO₃ aerogel can degrade MO completely after 40 min of illumination, while the corresponding aerogel before modification can only remove 80% of MO after 60 min. The present work not only complements the preparatory investigation of intricate aerogels but also offers a fresh perspective for the development of diverse perovskite aerogels with broad applications.