Abstract
Nitrogen doped graphene modified WO3 nanocomposites were synthesized through an effective methodology. The prepared photocatalysts were employed as active candidates for degradation of highly toxic organics i.e., 2, 4 dichloro phenol (2, 4-DCP) and methyl orange (MO). XRD profile of N-graphene showed complete reduction of GO into N-graphene. All diffraction peaks of WO3 along with N-graphene indicated monoclinic phase of WO3. SEM and TEM images of 3.0% N-graphene/WO3 have demonstrated the mixed morphology of irregular massive rod like blocks and round shaped particles of WO3 distributed on cracked sheets of N-graphene. Nitrogen defects in graphene altered zero band gap semi-metallic graphene to semiconducting material and increased the absorption edge of N-graphene/WO3 nanocomposites towards visible region as studied in DRS analysis. FTIR and Raman studies showed the strong connection between N-graphene and WO3 by making W−O−C surface linkage. The noticeable reduction in PL emission peaks of 3.0% N-graphene/WO3 indicated obvious separation of photo induced charge carriers. The study of radical scavengers suggested that holes (h+) and •OH are the main elements for the decontamination of both MO and 2, 4-DCP. XPS analysis shows all possible C−N bonding configurations in 3.0% N-graphene/WO3. 3.0% N-graphene/WO3 composite showed the maximum photo degradation of MO (~94.0%) and 2, 4-DCP (~81.0%). The synergism between N-graphene and WO3 results into more sporty sites on catalyst and restoring of sp2 structural defects in N-graphene lattice improve the transportation of charge carriers during photocatalysis. This work provides innovative strategies for designing the N-graphene/semiconductor nanosystems with enhanced photocatalytic phenomena in the environmental cleanup remedies.
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•Nitrogen doped graphene/WO3 nanocomposite functioned as energetic photocatalyst.•Nitrogen atoms in graphene produce unstable charge zone leading to polarization.•Graphene in WO3 provides conductive channels for the passage of charge carriers.•3.0% N-graphene/WO3 nanosystem showed the superior photocatalytic efficiency.•OH•and h+ radicals emerged as main active species for photocatalysis.