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ZnO nanorods have been synthesized on glass substrate by low-cost two step chemical bath deposition (CBD) method at low temperature. The ZnO seed layers have been coated on glass substrate by RF magnetron techniques with power 150 watt for 15 min. The influence of different growth time on the optical properties, energy band gap, Raman spectra and surface morphology of ZnO nanorods are investigated. The growth time are (0.5, 1, 2, 3, 4 and 5) h. The double beam UV visible (UV-5000), Raman Spectroscopy and field emission scanning electron microscopy have been used to characterize the optical properties (absorption and transmission), energy band gap, Raman spectra, surface morphology, diameter, distribution and homogeneity of produced ZnO nanorods. The results found that the growth time have significant effect on the optical properties, energy band gap, Raman modes, aligned, surface morphology, diameter, ZnO distribution and density. And It is observed that the absorbance of the growth times 4 and 5 h are higher than the other growth times of ZnO nanorods, which showed the good crystallinity of the other samples. The transmittance decreases sharply near UV region at wavelength around 385 nm due to the optical band gap absorption. The obtained energy band gap of ZnO nanorods decreases with increase in the growth time from 3.25 eV to 3.18 eV. From result, it was investigated that the growth time caused the average crystalline size increases and decreases defects causing the energy band gap decreased. From Raman spectra, it observed that the dominant and sharp peaks at approximately 100 cm-1 and 437 cm-1 for the ZnO nanorods grown of 4 h and 5 h as a growth times, which are corresponds to the intrinsic characteristics of the Raman active E2(low) and E2(high) modes of the hexagonal wurtzite ZnO, respectivly Also FESEM results shows that the growth time has a good playing role on the nanostructure growth orientation of the ZnO nanorods. [ABSTRACT FROM AUTHOR]

Vertically well-aligned ZnO nanorods arrays have been synthesized on ZnO seed layer coated glass substrates at low temperature using modified low-cost chemical bath deposition (CBD) method. The investigation of the influence of no air bubbles, air bubbles and oxygen bubbles inside the CBD reactor on the structural characteristics, morphological (diameter, length, aligned, distribution and homogeneously), elements chemical composition and optical properties of ZnO nanorods have been studied. This new modification of chemical bath deposition method shows the improved results over traditional chemical bath deposition method. The important results of this novel process are the good morphological, structural characteristic and optical properties of ZnO nanorods. These results obtained in just of 3.5 h growing time in the CBD reactor. On this modified CBD the growth time rate decreases about 1.5 h compared with the previous works. [ABSTRACT FROM AUTHOR]

In recent years, carbon quantum dots (CQDs) have received due attention with the versatile application. In this paper, the carbon source of CQDs preparation was classified systematically and scientifically for the first time. The unique optical properties of CQDs were comprehensively discussed in terms of its PL intensity and UV-vis spectrum. The morphology properties of CQDs were also deduced according to their TEM profiles. The graphitization degree were characterized using Raman and XRD. In addition, the preliminary application of CQDs in the field of catalysis and fluorescent probe was illustrated. The mechanism of CQDs in these fields was developed. [ABSTRACT FROM AUTHOR]