Polydopamine‐Mediated Gold Nanostructure‐Decorated Electrospun Polycaprolactone Fibers for Photocatalytic Dye Degradation

Abstract

AbstractMetallic nanoparticle (NP)‐decorated electrospun micro/nanofibers as an ideal photocatalytic system for the degradation of organic dyes may provide unique advantages in terms of 3D morphology with high surface area, well‐controlled porosity, low cost, good interconnectivity, and excellent flexibility. However, novel, flexible, low‐cost, and efficient fabrication methods are still demanded to obtain photocatalytic activity. In this report, for the first time, we propose gold NP (AuNP)‐decorated electrospun poly(Ɛ‐caprolactone) (PCL) membrane fibers through a conformal thin layer of polydopamine (PDA). Herein, PDA could reduce the Au3+ ions and enable the adsorption of AuNPs without using any reducing agent or seed material. The proposed system could degrade methylene blue after a 6‐h of daylight exposure with a rate constant of 4.83 × 10−3 and 4.64 × 10−3 min−1 for citrate‐stabilized AuNPs and reduction of Au ions cases, respectively. Even after fifth cycle of usage, AuNP‐decorated electrospun fibers showed reasonable catalytic activity without any significant change in their morphology and chemical content. For the case of rhodamine 6G, the same systems provided 55.2% and 64.1% of dye degradation within a 5‐h exposure. The proposed system presents unique advantages regarding control, flexibility, low cost, and efficiency in various catalytic applications.