Abstract
CuWO4 is a medium bandgap (2.3 eV) n-type semiconductor capable of photoelectrochemical water oxidation under applied electrical bias. Here, we show for the first time that suspended microcrystals CuWO4 evolve oxygen photocatalytically under visible illumination from solutions of 0.05 M AgNO3(10.8 μmol/hour; AQE of 0.561% at 400 nm) and 0.0002 M FeCl3(1.5 μmol/hour). No oxygen is detected with 0.002 M [Fe(CN)6]3-as sacrificial agent. The activity dependence on the redox potential of the acceptors is due to the presence of Cu2+based electron trap states in CuWO4. According to surface photovoltage spectroscopy and electrochemistry, these states are located on the particle surface, 1.8 eV above the valence band edge of the material. Controlling the chemistry of these states will be key to uses of CuWO4particles in tandem catalysts for overall water splitting. Figure 1
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
