2D Nanostructured MXene-Based Silver Nanoparticles for Photocatalytic Degradation of Safranin Dye

Abstract

Due to their unique chemical structure, MXenes have been recognized as a potential material, having a high surface area, high thermal and electrical conductivity, and a tunable band gap, showing great hydrophilicity and stability. The adsorption and reducing properties of MXene-based 2D nanomaterials make them efficient photocatalysts for degrading organic pollutants. Silver nanoparticles were synthesized over the exfoliated MXene sheets (1:50 and 1:20 by weight to silver salt) using polyvinyl pyrrolidone as a dispersant. The elemental composition and morphology of the nanocatalysts Ag20@Ti3C2Tx and Ag50@Ti3C2Tx were analyzed by X-ray diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray (EDX) spectroscopy, and field-emission scanning electron microscopy (FESEM). FESEM micrographs reveal porous exfoliated Ti3C2Tx sheets obtained by continuously stirring Ti3AlC2 for 44 h at 60 °C, providing a platform for the growth of Ag nanoparticles. Diffused reflectance spectroscopy (DRS) indicates that the bare silver nanoparticles show a decrease in the band gap value from 2.4 to 1.35 and 1.41 eV in Ag50@Ti3C2Tx and Ag20@Ti3C2Tx, respectively, which enables the nanocomposites to show excellent catalytic performance and degrade around 99% of safranin dye within 15 min at a concentration of 5 mg Ag50@Ti3C2Tx.