Synthesis of γ-graphyne by modified mechanochemistry with enhanced adsorption of organic dyes

Abstract

The γ-graphyne is a new two-dimensional carbon nanomaterials with unique sp and sp2 hybridized carbon atoms, uniform distribution of nanotopological pores, and high degree of π-conjugation, making it a promising candidate in water pollutant treatment. Herein, γ-graphyne was synthesized by a modified mechanochemical method and used as adsorbents for removing of organic dyes. Raman spectra, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are performed to confirm the chemical structure and morphology of γ-graphyne. The maximum adsorption capacities of γ-graphyne for rhodamine B (RhB), methylene blue (MB) and congo red (CR) obtained through kinetic and isotherm analysis are 386.10, 357.14 and 254.45 mg/g, respectively，which are in good accordance with the experimental results of 383.64, 359.72 and 242.44 mg/g. The calculated adsorption energies of −20.0995, −12.5219 and −8.3647 kCal/mol, respectively, for RhB, MB and CR, which characterized the possible adsorption sites, give more deep understanding of the experimental results regarding the remarkable absorbability of γ-graphyne. Our work sheds light on synthesis of γ-graphyne for the future development of excellent adsorbents.