Simultaneous in Situ Exfoliation of Titanate and Zn-Cr Layered Double Hydroxides with a Copolymer for Photocatalytic Degradation of Organic Pollutants

Abstract

A binary polymeric hybrid nanocomposite has been synthesized by simultaneous grafting of vinylic monomers on dextrin, followed by in situ exfoliation of layered titanate (LT) and Zn-Cr layered double hydroxide (LDH) (g-Dext/LT/LDH). Here, the self-assembling between in situ exfoliated titanate and LDH nanosheets has been carried out by monitoring pH between 6.5 and 7, where the oppositely charged nanosheets experience maximum electrostatic interactions among them. The g-Dext/LT/LDH nanohybrid reveals a higher activity around 96% degradation of ciprofloxacin under natural sunlight irradiation in comparison to the bare LT, LDH, and LT/LDH, providing strong evidence for the superiority of the intimate hybridization between two nanosheets. The improvement of photocatalytic performance of g-Dext/LT/ LDH is attributed to the formation of a heterolayer structure by combining oppositely charged nanosheets, which synergistically improves the photocatalysis process by increasing the surface area and optical absorption property via reducing the migration distance of the photogenerated electron-hole pair and efficiently promoting their separation. Additionally, the antibacterial properties of g-Dext/LT/LDH have also been investigated against Bacillus pumilus (Gram-positive) and Enterobacter cloacae (Gram-negative) bacteria by the disc diffusion study.