Piezocatalytic removal of water bacteria and organic compounds: a review

In the context of climate change, freshwater shrinkage and industrialization, human diseases are increasing due to water pollution by toxic chemicals and pathogenic bacteria, calling for advanced methods to treat contaminated water. Here we review piezocatalysis, an overlooked method to degrade organic pollutants and inhibit bacteria. Recent research shows that the properties of piezoelectric materials have remarkably progressed due to a high surface area and a built-in electric field at the nanolevel. This induces an efficient charge carrier generation, which allows fast reaction mediated by reactive oxygen species. We discuss bacterial growth, methods for water treatment and the piezocatalytic mechanism with focus on charge generation, cavitation and bacterial inactivation by reactive oxygen species. We present applications to the removal of dyes and pathogenic bacteria.