Comparison of photocatalytic activity of exfoliated graphitic carbon nitrides in degradation of organic pollutant in water

In recent years one of the main current worldwide problems is development of many industrial, agricultural and urban human activities that occasion the growth of water pollution by organic compounds. A suitable solution to the problem is using heterogeneous photocatalysis which utilizes solar energy. Graphitic carbon nitride with specific properties such as small band gap of 2.7 eV, nontoxic and low-cost is considered as a good visible-light-driven photocatalyst. It is potentially used for degradation of organic pollutants, production of hydrogen in water splitting, photocatalyst conversion of Co2 to different fuels and so on. The exfoliation percent of graphitic carbon nitride layers have a direct effect on its photocatalytic performances. In this paper, two different methods were used to exfoliate graphitic carbon nitride, exfoliation with a) direct calcination and b) mixing with isopropanol (IPA) and then calcination. The prepared photocatalysts were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). It was found that photocatalytic activity of exfoliated g-C3N4 in degradation of Rhodamine B (RhB), as an organic pollutant, was efficiently increased based on exfoliation method.A comparison of RhB removal with graphitic carbon nitride exfoliated with different methods were made. It was found that the graphitic carbon nitride exfoliated with direct calcination can completely degrade RhB faster than that exfoliated with IPA.