Investigation on the photoconductivity of polyoxometalates†
Abstract
Polyoxometalates (POMs), a class of molecular metal-oxo cluster compounds based mainly on Mo, W, and V elements, have shown superior physicochemical properties and various applications. In this study, we investigate the photoconductivity of Keggin-type tungsten-series POMs, H3PW12O40, Na3SiW12O40, Na3GeW12O40 and Na6H2W12O40, considering that photoconductivity can be closely related to the potential applications in sensors, photodetectors, photovoltaics, and photocatalysis. The results from the photoconductivity measurements demonstrate that the photoconductive performance of the POM is clearly dependent on the type of POM. Moreover, H3PW12O40 exhibited a much higher photocurrent than the others; this may be due to the different photogenerated electron–hole recombination rate and photogeneration efficiency of the POMs. Furthermore, H3PW12O40 exhibited a good sensing performance for ethanol gas.