PDF Publication Title:
Text from PDF Page: 165
Chapter 6 – Production of Few Layer Graphene in Aqueous Media for Biological Studies Figure 6.2: a) Example experimental set up of dialysis procedure. Graphene dispersions were contained within the dialysis bag, secured by knots top and bottom, and dialysed against stepwise 10× dilution volumes of deionised water to achieve the solvent dilutions indicated. b) Photographs of stable dispersions obtained after step-by-step dialysis. Each dialysis step was carried out with gentle stirring for 12 hr. The step-wise dialysis of the graphene dispersions was carried out as shown in Figure 6.2a; 100 v/v%10 v/v%1 v/v%0.1 v/v%. In a typical procedure, the dialysis bag was filled with the starting graphene dispersion (100 v/v% organic solvent) and secured by knots on both ends followed by immersion of the bag in (1:10 ratio) DI water. The dialysis step was assisted by gentle stirring over 12 hr. During the dialysis procedure, the organic solvents diffused from the inside (high concentration) to the outside (low concentration) of the dialysis bag through the semipermeable membrane, and vice versa for water. This diffusion resulted in an equilibrium concentration of organic solvent and water on either side of the dialysis membrane. These steps were repeated again in a stepwise fashion by replacing the outside liquid with fresh DI water (1:10 ratio). Stable dispersions of G/DMF and G/NMP were obtained at different levels of dialysis (Figure 6.2b). The highlighted stable dispersions contained only 0.1 v/v% organic solvent and 99.9 v/v% water. 6.2.3. Confirmation of dialysis UV-Visible spectroscopy confirmed the extent of dialysis of the dispersions by monitoring the solvent’s UV cut-off wavelength, the wavelength at which the solvent absorbance in a 1 cm path cell is equal to 1 a.u. (water in reference cell).379 The UV cut-off wavelengths of 100 v/v% DMF and NMP (against 100 v/v% water) are 268 nm and 285 nm, respectively.380, 381 165PDF Image | PRODUCTION AND APPLICATIONS OF GRAPHENE AND ITS COMPOSITES
PDF Search Title:
PRODUCTION AND APPLICATIONS OF GRAPHENE AND ITS COMPOSITESOriginal File Name Searched:
graphene-production-applications.PDFDIY PDF Search: Google It | Yahoo | Bing
Salgenx Redox Flow Battery Technology: Power up your energy storage game with Salgenx Salt Water Battery. With its advanced technology, the flow battery provides reliable, scalable, and sustainable energy storage for utility-scale projects. Upgrade to a Salgenx flow battery today and take control of your energy future.
| CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com | RSS | AMP |