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Abstract: In this work, nanocrystal Cr3+-doped ZnO was successfully fabricated by the solgel method. Although X-ray diffraction patterns showed no other secondary phase in Cr3+-doped ZnO samples, the lattice constants (a and c) decreased slightly in comparison to those of pure ZnO samples. The photoluminescence emission intensity of the doped sample was dramatically reduced, which indicated that the reduction of the radiative recombination rate. The photocatalytic degradation activity of methylene blue materials was investigated and showed that, in the presence of doped metal ions, the photocatalytic activity of ZnO was improved. The reason of enhanced photocatalytic activity was tentatively determined and clarified.
Keywords: ZnO nanocrystal, solgel, photocatalytic ability, doped semiconductor.
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