Influence of Copper as a Co-Catalyst of Potassium Hexaniobate Nanotubes on the Photocatalytic Hydrogen Evolution from a Methanol Aqueous Solution
In the presence of Cu2+ ions, the photocatalytic hydrogen evolution from a methanol aqueous solution was achieved when potassium hexaniobate nanotubes were used as the catalyst. It was found that there existed a photo-induced period in the initial reaction stage. Furthermore, the photo-induced period was prolonged by increasing the amount of Cu2+ ions. After that, the rate of hydrogen evolution was dramatically improved. Combined with the reaction phenomena and the result of the photocatalytic hydrogen evolution, it was deduced that the Cu2+ ions captured the photo-generated electrons of potassium hexaniobate nanotubes in the photo-induced period. Consequently, the Cu2+ ions were reduced and deposited on the potassium hexaniobate nanotubes. When the mass ratio of Cu to potassium hexaniobate nanotubes was 3 wt%, the rate of hydrogen evolution over the catalyst reached 21.9 mmol·g-1·h-1, which could almost match with Pt as a co-catalyst. These results showed that Cu was an effective alternative to Pt as a co-catalyst of potassium hexaniobate nanotubes for the photocatalytic hydrogen evolution from the methanol aqueous solution.
Zhong Cao, Xueqiang Cao, Lixian Sun, Yinghe He
X. L. Zhao et al., "Influence of Copper as a Co-Catalyst of Potassium Hexaniobate Nanotubes on the Photocatalytic Hydrogen Evolution from a Methanol Aqueous Solution", Advanced Materials Research, Vols. 239-242, pp. 3298-3301, 2011