In this paper, a simple, cost effective, and scalable process for production of fewlayer graphene is reported by combining ball milling with exfoliants. The graphene was derived from low-cost graphite, which was subjected to high-energy ball milling in an aqueous medium containing a strong exfoliant (1-pyrenecarboxylic acid) and a common solvent methanol. Such a combinatorial approach has not been used before. At a fixed concentration of 1-pyrenecarboxylic acid, the extent of exfoliation was found to be strongly dependent upon the energy input from the ball milling process (expressed as number of hours of milling) and the solvent used. The graphene produced had the distinctive Raman signature, x-ray diffraction crystallinity, scanning electron microscopic image features, transmission electron microscopic images, and high conductivity values (6.7 Â 10 3 S m À1 ) in 4-probe electrical measurements all of which compared reasonably with typical values achieved for few-layer graphene. Application of the few-layer graphene was investigated as an electrode for supercapacitors. The graphene-coated electrode showed good specific capacitance and area capacitance ($176 F g À1 and 1.6 F cm À2 ), superior to conventionally processed graphene. Also demonstrated is good stability in multiple cyclic voltammetric cycles as also a low fade in capacitance after 100 cycles. Based on the obtained characteristics, which show high degree of fidelity when compared to commercial graphene, the few-layer graphene was considered to be a good cost-effective and scalable alternative for applications in energy and other fields. V C 2013 AIP Publishing LLC. [http://dx.doi.org/10.1063/1.4809794] 033123-2 Aparna et al. J. Renewable Sustainable Energy 5, 033123 (2013) 033123-5 Aparna et al. J. Renewable Sustainable Energy 5, 033123 (2013) 033123-8 Aparna et al.
Photocatalysis speeds up the photoreaction in the presence of a catalyst. TiO 2 has low toxicity, less resistance and less corrosion and has semiconductor properties. Its strong oxidative potential of the positive holes oxidizes water to create hydroxyl radicals. Moreover, TiO 2 has been proven to be a tremendous photocatalyst compound by which many organic substrates have been shown to be oxidatively degraded under UV irradiation. In this research the photocatalytic effect of TiO 2 on degradation of Brilliant Green (BG) was studied. In conjunction the effect of dopants such as Zn and Cu on photocatalysis of TiO 2 were also studied. Structural and morphological properties of TiO 2 were characterized by SEM and XRD. From this research the initial concentration of sample, pH of samples, chemical structure of dyes and catalyst loading were most valuable parameters for dye degradation. TiO 2 showed excellent result on degradation of BG compared with doped TiO 2. 99% degradation was obtained in presence of TiO 2 , followed by TiO 2 /Zn for 87% and TiO 2 /Cu for 46%. TiO 2 doped with transition metals can increase or decrease photocatalytic degradation of dyes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.