Title
Highly efficient charge transfer through double Z-scheme mechanism by Cu promoted MoO3/g-C3N4 hybrid nanocomposite with superior electrochemical and photo catalytic performance
Author
Sulagna Patnaik, Gayatri Swain, Kulamani Parida
Year
2018
Journal
Nanoscale
Abstract
A novel Cu-MoO3/g-C3N4 hybrid nano composite was successfully synthesized by a two step strategy of one-pot pyrolysis followed by impregnation method. The structural, phase, morphology and electronic environment of MoO3, g-C3N4 and Cu in the composite has been determined by various characterization methods. The oxygen vacancies of MoO3 have been ascertained by UV-DRS, Raman and XPS analysis. The formation of heterostructure has been characterised by electrochemical measurement. The photo catalytic performance of the composite was investigated by water reduction reaction and reduction of an important inorganic pollutant Cr (VI). In presence of Cu NPs as cocatalyst, the H2 evolution of MoO3/g-C3N4 hybrid was found to be 652 μmol/h with an apparent energy conversion efficiency of 13.46 %, and Cr (VI) was reduced up to 95% by using citric acid as a hole scavenger. The remarkably enhanced photo catalytic performance was attributed to the combined effect of the double Z-scheme mechanism and defective MoO3. In situ formation process of MoO3/g-C3N4 hybrid follows a direct Z-scheme charge transfer by generating a great number of defects at the solid-solid interface, similar to that of a conductor and offer low electric resistance. Whereas, loading Cu NPs builds up an indirect Z-scheme charge transfer to establish double Z-scheme charge transfer mechanism. This hybrid material produces a photocurrent density of 12.1 mA cm-2 in good agreement with the photo catalytic activity. This work highlights the facilitation effect of MoO3 due to oxygen vacancy and charge transfer through double Z-scheme mechanism to opens up a new window in the field of 2D nanostructured photo catalytic materials.
Instrument
FP-8300
Keywords
Luorescence, Photoluminescence, Nanostructures, Materials