In modern chemistry, there is a high demand for materials that can accelerate particles and generate energy at the same time. Among them are nanocomposites based on polyvinylidene fluoride (a polymer capable of converting mechanical energy into electricity) and bismuth ferrite, a magnetoelectric nanomaterial that undergoes chemical transformations under the influence of light. This combination makes it possible to create intelligent materials with the ability to self-capture energy from the environment.
The scientists from Dagestan State University have synthesized composite films by integrating bismuth ferrite nanoparticles into the polyvinylidene fluoride matrix. The experiment showed that, when exposed to ultraviolet light, the material decomposes methylene blue, an organic dye used in the medical, dyeing and chemical industries. The reaction efficiency was 97%, going down to 83% with ultrasound treatment (the lower the percentage, the higher the efficiency).
After analyzing the reaction mechanism, the authors found that hydroxyl radicals, particles formed under the influence of light and ultrasound, play a key role in the destruction of the dye. They attack the pollutant molecules, causing successive chemical transformations and changes in the structure of the molecule. The scientists also found that the composite can decompose pollutants even in an alternating low-frequency magnetic field comparable to the magnetic field near a powerful speaker. In that case, decomposition efficiency reached 38% without additional light or ultrasound exposure. This opens up new possibilities for the creation of magnetically controlled catalysts that can operate in weak alternating magnetic fields.
The new material is also capable of collecting and accumulating energy. When exposed to ultrasound and mechanical compression, the stress in the composite increased by 1.9 times compared to pure polyvinylidene fluoride. Thanks to the magnetoelectric effect, the material generated an electric charge even in a weak alternating magnetic field. During experiments, the film was placed next to the electrical wire of a household appliance, which showed that it was able to collect the so-called parasitic electromagnetic energy, i.e., weak electromagnetic fields that form around operating electrical devices and usually remain unused.
“The material we have developed combines catalytic and energy functions, which makes it a promising one for environmentally-friendly water purification technologies, autonomous sensors and energy-efficient devices. In the future, we plan to explore the option of integrating these composites into flexible power sources and energy storage systems,” Farid Orudzhev, candidate of chemical sciences, is quoted as saying by the Russian Science Foundation.
