carbon pawan.pdf (1.82 MB)
Hexamolybdenum clusters supported on graphene oxide: Visible-light induced photocatalytic reduction of carbon dioxide into methanol
Hexamolybdenum (Mo6) cluster-based compounds namely Cs2Mo6Bri
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and
(TBA)2Mo6Bri
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6 (TBA = tetrabutylammonium) were immobilized on graphene oxide (GO)
nanosheets by taking advantage of the high lability of the apical bromide ions with
oxygen-functionalities of GO nanosheets. The loading of Mo6 clusters on GO nanosheets
was probed by Fourier-transform infrared (FTIR) spectroscopy, X-ray photoelectron
spectroscopy (XPS), high resolution transmission electron microscopy (HRTEM) and elemental
mapping analyses. The developed GO-Cs2Mo6Bri
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x and GO-(TBA)2Mo6Bri
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x
composites were then used as heterogeneous photocatalysts for the reduction of CO2 under
visible light irradiation. After 24 h visible light illumination, the yield of methanol was
found to be 1644 and 1294 lmol g1 cat for GO-Cs2Mo6Bri
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x and GO-(TBA)2Mo6Bri
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x,
respectively. The quantum yields of methanol by using GO-Cs2Mo6Bri
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x and
GO-(TBA)2Mo6Bri
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x as catalysts with reference to Mo6 cluster units presented in 0.1 g
amount of catalyst were found to be 0.015 and 0.011, respectively. The role of immobilized
Mo6 clusters-based compounds on GO nanosheets is discussed to understand the
photocatalytic mechanism of CO2 reduction into methanol.
