Peroxymonosulphate-mediated metal-free pesticide photodegradation and bacterial disinfection using well-dispersed graphene oxide supported phosphorus-doped graphitic carbon nitride

The current work emphasized the facile fabrication of PCN/GO nanocomposites via a straight forward sonochemical method. The thermal polycondensation method was used for the preparation of graphitic carbon nitride (GCN) and phosphorous doped graphitic carbon nitride (PCN) photocatalysts using melamine and BmimPF(6)(1-Butyl-3-methylimidazolium hexafluorophosphate) precursors. Phosphorous doped g-C(3)N(4)with different wt % ratio of phosphorous (0.05, 0.1, and 0.3%) was successfully fabricated and coupled with graphitic oxide (GO) for malathion degradation and bacterial disinfection. Phosphorous doping improved the electronic and textual properties of g-C(3)N(4)and augmented solar light-responsive range. On the other hand, simultaneously, the GO support simultaneously facilitated the charge separation and transportation, which was validated by PL and EIS analysis. The extremely organized porous structure of PCN/GO nanosheets expanded active sites, quickened electron transmission rate, and caused strong adsorption of pollutants. Specific surface area (S-BET) of 0.1 wt% PCN/GO and PCN photocatalysts was 13.6840 and 2.8401 m(2) g(-1), respectively. The addition of peroxymonosulfate (PMS) in photodegradation processes augmented the photodegradation ability of nanocomposites due to the triggering of sulfate radical (SO4 center dot(-)) based advanced oxidation process. The influence of different reaction parameters, including a concentration of PMS, catalyst dosage, initial concentration of the pesticide, and pH, was also assessed in the photodegradation process. All the photodegradation processes followed the pseudo-first-order kinetics as the regression coefficient (R-2), and values of linear graphs were from 0.95 to 0.98. The nanocomposite 0.1 wt% PCN/GO/PMS displayed the highest photodegradation efficiency, i.e., 98%, followed by 0.1 wt% PCN/GO (95%) and other photocatalysts. Similarly, 98%Escherichia coli(E.Coli) bacterial disinfection was observed for 0.1 wt% PCN/GO nanocomposite.