This research article provides a pathway of controlled growth of ZnO nano-rods, -flowers, -needles or -tubes without external chemical catalysis, via a simple wet chemical method by control of synthesis temperature. Morphological effects on structural and optical properties are studied by Ultraviolet-visible (UV-vis) spectroscopy shows slight enhancement in the band gap, with increasing synthesis temperature. Photoluminescence (PL) data indicates the existence of defect in the nanomaterials, which is more elaborately explained by schematic band diagram. A sharp and strong peak in Raman spectroscopy is observed at ∼438cm−1 is assigned to the E2high optical mode of the ZnO, indicating the wurtzite hexagonal phase with high crystallinity.

Monodispersed ZnO nanoparticles have been synthesised in ethylene glycol medium using zinc acetate and sodium hydroxide at room temperature through ultrasonic treatment. The monodispersed ZnO nanoparticles were characterized by XRD, TEM, SEM, and optical spectroscopy. The results indicate that ZnO shows the hexagonal wurtzite structure having 8 nm average particle size with the band gap of 3.93 eV. ZnO nanoparticles blended with P3HT show the improvement in the interchains and intrachains ordering as compared to pure P3HT. The power conversion efficiency of P3HT/ZnO solar cell is found to be 0.88%, which is comparable with the result obtained by other researchers.

aGraphene is a wonder material possessing unique properties; however, graphene prepared by exfoliation of graphite has property to restack because of van der Waals interactions to form graphite. This restacking can be prevented by insertion of large molecules like fullerene, which not only exfoliates graphite layer but also prevents restacking of prepared graphene sheets. The present article also describes a mild method of graphite oxide synthesis (GO) for lower degree of oxidation resulting in less defected (ruptured carbon framework) graphene sheets. Exfoliation is performed by intercalation of large fullerene molecules by aqueous reaction of fullerene hydroxide (fullerenol) with the epoxy functionalities on graphite oxide to prepare fullerene intercalated graphite (G-Fol). Fullerene functionalization of GO to form G-Fol has been established by FTIR spectroscopy, UV-Vis spectroscopy, TGA and number of layers has been ascertained by Raman spectroscopy, XRD and HRTEM. Stable exfoliation of G-Fol has been confirmed by change in absorbance with time. Photoluminescence property of the material is also evaluated by fluorescence emission and excitation measurement at different excitation and emission wavelengths, respectively. The present article explains a new method of exfoliation of graphite to form stable functionalized graphene layers with fewer defects for future applications as buffer layer in electronic devices.

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