ZnO-SnO2 nanocubes for fluorescence sensing and dye degradation applications

ZnO-SnO2 nanocubes were used as promising material for efficient sensing of p-nitrophenol and faster photo catalytic degradations of dyes like methyl orange (MO), methylene Blue (MB) and acid orange 74 (AO74). ZnO-SnO2 nanocubes were prepared by the facile solution process at 50 degrees C using Zn(NO3)(2)center dot 6H(2)O and SnCl2 center dot 2H(2)O as a precursor in the presence of ethylenediammine. The synthesized material was examined for its morphological, structural, crystalline, optical, vibrational, and compositional studies by using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy. FESEM studies revealed the formation of well-defined ZnO-SnO2 nanocubes where the structural examinations revealed the formation of a crystalline tetragonal rutile phase for SnO2 with some crystal sites doped with Zn. The as-synthesized nanocubes were explored for their photocatalytic activities towards three different dye viz. MO, MB, and AO74. Practically, complete degradation of AO74 was seen within 4 minutes of photo-irradiation in the presence of 0.05 g ZnO-SnO2 nanocubes. However, 97.17% and 41.63% degradations were observed for MB and MO within 15 and 60 minutes, respectively. All the dye degradation processes followed the pseudo-first-order kinetic model. Moreover, the as-synthesized nanocubes were utilized to fabricate highly sensitive and selective fluorescent chemical sensor for the detection of p-nitrophenol (PNP). ZnO-SnO2 nanocubes showed a very low detection limit of 4.09 mu M for the detection of PNP as calculated according to the 3 sigma IUPAC criteria. Further, the as synthesized ZnO-SnO2 nanotubes were found to be highly selective for p-nitrophenol as compared to the other two isomers.

Automated summary

ZnO-SnO2 nanocubes are used as efficient materials for detecting p-nitrophenol and quickly degrading dyes, with a low detection limit and high selectivity.