One-step preparation of a novel SrCO3/g-C3N4 nano-composite and its application in selective adsorption of crystal violet

A novel kind of nanoparticle SrCO3/g-C3N4 was prepared using strontium carbonate (SrCO3) and melamine (C3H6N6) as raw materials via one-step calcination. The formation of SrCO3/g-C3N4 was confirmed from the X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Brunauer-Emmett-Teller (BET) and X-ray photoelectron spectroscopy (XPS) analysis. Its selective adsorption performance was evaluated towards crystal violet (CV), rhodamine B (RhB) and methylene blue (MB). The results showed that the SrCO3/g-C3N4 had selective adsorption ability of CV. Furthermore, adsorption measurements of CV were conducted to investigate the influences of contact time, initial concentration, initial dye solution pH value and adsorbent dosage. The maximum removal rate of CV was 98.56% when the initial concentration was 1600 mg L-1. The kinetic study indicated the adsorption of CV followed the pseudo-second-second model well. The adsorption efficiency of SrCO3/g-C3N4 was greater (97.46%) than that of g-C3N4 (31.30%) and SrCO3 (17.30%). It could be deduced that the synergistic effect of conjugation interaction of g-C3N4 and the electrostatic attraction of SrCO3 might be the main driving force for the superb adsorption of CV.