Oriented 2.0.0 Cu2O nanoplatelets supported on few-layers graphene as efficient visible light photocatalyst for overall water splitting

- Oriented 200 Cu2O nanoplatelets grafted on few layers graphene have been prepared by pyrolysis of Cu2+-chitosan.
- Oriented 200 Cu2O grafted on graphene exhibit photocatalytic activity for overall water splitting.
- A rate of 19.5 mmoles of H2 per gram of catalyst per hour has been achieved in the absence of sacrificial electron donor.
- Cu2O grafted on graphene is remarkable stable upon prolonged irradiation

Cu2O nanoplatelets with preferential 2.0.0 facet orientation supported on few layers graphene were prepared as films in a single step by pyrolysis at 900 °C under inert atmosphere of Cu2+-chitosan precursor. Cu2O¯/fl-G films exhibit a photocatalytic activity for overall water splitting of 19.5 mmol/gCu+G h. This value is about 4 orders of magnitude higher than the photocatalytic activity measured for unoriented Cu2O nanoparticles on few-layers graphene or than commercial Cu2O nanoparticles and about three orders of magnitude higher than the activity reported in the literature for Cu2O nanoparticles. In addition Cu2O nanoparticles on few-layers graphene retain about 50% of its photocatalytic activity after 6 days of continuous irradiation. It is proposed that this activity and stability arises from the combination of features derived from the pyrolysis preparation procedure including strong Cu2O-graphene grafting, the role of graphene as cocatalyst and preferential 2.0.0 facet orientation.

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