Spiky nanohybrids of titanium dioxide/gold nanoparticles for enhanced photocatalytic degradation and anti-bacterial property

Abstract We present a facile two-step procedure for synthesizing spiky nanohybrids of titanium dioxide/gold (TiO 2 /Au) nanoparticles. In this process, spiky TiO 2 is obtained using a hydrothermal method, followed by the introduction of plasmonic Au nanoparticles (AuNPs) via a photoreduction approach in which titanium fluoride and chloroauric acid tetrahydrate are used as raw materials. The photodegradation property of the resulting sample was evaluated according to the removal of Rhodamine B (RhB) and ciprofloxacin (CIP) via excitation with visible light. Additionally, the antimicrobial property of the spiky TiO 2 /Au nanoparticles was examined with respect to the suppression of the growth of Escherichia coli ( E. coli ). Compared with commercial TiO 2 , the spiky TiO 2 /Au nanoparticles exhibited a significantly enhanced photocatalytic efficiency in persistent organic pollutant degradation and bacteria inactivation under simulated environmental conditions. The photocatalysis mechanism primarily entails the combination of AuNPs with spiky TiO 2 nanoparticles, which increases the optical path owing to the unique spiky structures of the latter. This results in an improved light-harvesting efficiency based on the localized surface plasmon resonance (LSPR) of AuNPs and the promotion of the charge-separation efficiency through electron-trap processes. These nanoparticles realize the objective of effectively addressing the inherent weaknesses of bare TiO 2 and potentially facilitate new fitting approaches for applications in sewage treatment and marine antifouling paint.