Tahir Muhmood

Efficient and stable ZrO2/Fe modified hollow-C3N4 for photodegradation of the herbicide MTSM

Hollow graphitic carbon nitride (HCN) ZrO2/g-C3N4 hybrid composites (HCN–ZR) and the target catalyst Fe/ZrO2/g-C3N4 (HCN–FZR) were prepared successfully by a solvo-thermal method and evaluated for photo-degradation of organic pollutants, i.e. MO, and herbicides, metsulfuron methyl (MTSM). These materials were characterized by a variety of techniques, including Fourier transform infrared spectroscopy, UV-vis spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, HPLC-MS and scanning electron microscopy. The characterization and degradation results showed that FZR particles are well distributed on the surface of HCN to give a photo-catalytically active material. Photodegradation split MTSM completely into a lot of intermediate products, as depicted in the HPLC-MS results. Mooring of FZR on HCN increased the surface-area and light absorption capability of HCN–FZR, due to heterojunction formation between the semiconductors, which retarded electron–hole recombination and enhanced the photo-activity.

Encapsulating nano rods of copper–biphenylamines framework on g-C3N4 photocatalysts for visible-light-driven organic dyes degradation: promoting charge separation efficiency

For the first time we have successfully constructed semi conductive copper–biphenylamines framework hybrid photocatalysts to degrade organic pollutants. Cu complexes sensitized photocatalysts of g-C3N4, i.e. CN-Cu(BN), CN-Cu(PD) and CN-Cu(BA), have been successfully tested for photocatalytic degradation of organic pollutants under visible light illumination, and a significant enhancement in catalytic activity was observed for CN-Cu(BA) in comparison to pristine g-C3N4. The modified material creates a charge separation with the electrons populating the higher CB and the holes the lower VB, thus enhancing the redox reaction power of the charge carriers. CN-Cu (BA) can easily degrade 99% of RhB in 1.5 hours and 60% of phenol in 2 hours. While the degradation efficiency of CN-Cu(BN), CN-Cu(PD) and g-C3N4 is lower than that of CN-Cu(BA). The kobs for CN-Cu(BN) is 0.01985 min−1, 5.2 times higher than that of g-C3N4, and that of CN-Cu(BA) is 0.0292 min−1 which is 7.55 times greater than that of pristine g-C3N4. These degradation outcomes are favourable for developing a modified catalyst in bulk amount and its application. The strong holes can directly degrade RhB and phenol. Promoting the injection of electrons from g-C3N4 into the copper unit as well as strengthening the electronic interactions between the two units enhanced its activity.