Graphitic carbon nitride based heterojunction nanocomposite for degradation of organic dyes

In this work, the novel graphitic carbon nitride and sodium iron titanium oxide (NFTO) (chemical formula with the stochiometric ratio: Na2Fe0.6Ti0.4O6) a metal complex based nanocomposite are studied. The graphitic carbon nitride is prepared by facile, green and eco-friendly method using melamine as a precursor and the metal complex containing Na, Fe, and Ti metals is prepared by two step process. The nanocomposites of prepared graphitic carbon nitride and metal complex are prepared in 10 wt% and 30 wt% compositions. The nanocomposites are characterized using FTIR, XRD, SEM, and TEM techniques and the elemental composition of the metal complex is calculated using XPS analysis. TEM characterization clearly indicates the formation of heterojunction in the nanocomposites. The energy band-gap of nanocomposites was measured using the Tauc plot and it is found that on the formation of heterojunction in nanocomposites the energy bandgap reduces to 2.00 eV from 2.50 eV for pure graphitic carbon nitride. The prepared nanocomposites are analyzed for photocatalytic degradation of Rhodamine and methylene blue dyes. The kinetics of degradation of dyes is studied using a UV–visible spectrophotometer and the nanocomposite of 30 wt% compositions degraded the dye in 255 s while 10 wt% nanocomposites degraded the same in 285 s. The methylene blue dye is degraded in 360 s by the nanocomposite of 30 wt% compositions. The rate constant, activity coefficients of the degradation reactions are also calculated using ln (Ct/Co) vs time plot. The activity coeffiecient calculated using ln (Ct/Co) vs time plot is highest for the degradation of RhB using the nanocomposite 30 wt% composition.