Enhanced degradation of organic contaminants using a PVDF/AC-NaCl piezocatalyst: effect of geometric design in fluid flow environments

Abstract

Technologies to treat water using the piezoelectric effect of polyvinylidene difluoride (PVDF) have attracted significant research attention, with many studies focusing on exploiting the pressure from fluid flow on piezoelectric catalysts. This pressure varies according to catalyst geometry, potentially enhancing the effectiveness of water treatment. Here, we describe the synthesis of a triangular prism of PVDF/activated carbon-NaCl with a piezoelectric strain coefficient of 35 pC N⁻¹, generating a maximum voltage of 5.25 × 10⁻¹ V. This led to the formation of H⁺ and ·OH radicals, achieving degradation efficiencies of 99.91%, 97.12%, 95.03%, and 99.53% for rhodamine B, 4-nitrophenol, phenol, and tetracycline, respectively. Energy consumption was 38.67 kW h per m³ per order, a more efficient value than that produced by a piezocatalyst with a greater piezoelectric strain coefficient and conventional advanced oxidation processes. These findings deepen our understanding of how the efficiency of water treatment in piezocatalysts using fluid flow can vary depending on catalyst geometry and may be used to design other piezocatalysts in fluid flow.