Synthesis, characterization and application of graphene oxide in self consolidating cementitious systems. (16th August 2021)

• Record Type: Journal Article
• Authors: Ullah, Majeed; Imtiazi, Shahzada Burhan Ahmad; Khushnood, Rao Arsalan; Pervaiz, Erum; Ahmed, Wisal; Ullah, Asad; Qureshi, Zarar Ali
• Is Part Of: Construction & building materials. Volume 296(2021)
• Publication Date: 2021-08-16
• Subjects: ASTM American Society for Testing Materials -- BET Brunauer–Emmett–Teller -- CSH Calcium Silicate Hydrate -- CNTs Carbon Nanotubes -- EDX Energy Dispersive X-Ray Spectroscopy -- EMI Electromagnetic Interference -- FESEM Field Emission Scanning Electron Microscopy -- FTIR Fourier Transform Infrared Spectroscopy -- GO Graphene oxide -- IUPAC International Union of Pure and Applied Chemistry -- MIP Mercury Intrusion Porosimetry -- NC Nanoclay -- NS Nano-Silica -- SP Super Plasticizer -- SCCs Self-compacting cementitious systems -- SCMs Self-compacting mortar systems -- SEM Scanning Electron Microscopy -- TGA Thermal gravimetric analysis -- VMAs Viscosity Modifying Agents -- VMAs Viscosity modifying agents -- XRD X-ray diffraction -- w/c Water to cement ratio; Self-Compacting mortars -- Graphene oxide -- Improved Hummer's method -- Raman spectroscopy -- Viscosity -- Electromagnetic interference Shielding; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2021.123623
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: GO is successively synthesized using Improved Hummer's Method. GO controls segregation and modifies flow attributes of self compacting matrices. GO reduces autogenous and plastic shrinkage by microstructure refinements. GO adds in compressive and flexure resistance alongside fracture toughness at fractional dose. GO offers EMI shielding of 92% in SCMs experiencing radio frequency of 8–10 GHz. Abstract: Segregation is, in fact, a predicament, associated with the use of self-compacting cementitious mortars. Viscosity modifying agents can avert this problem however their use motivates attrition in the mechanical strength. One possible solution to this problem lies in the inclusion of nanomaterials to self-compacting cementitious mortars, which owing to their large surface area, not only lessen the segregation problem but also increase the mechanical strength. One such effort is made in this research using synthetic Graphene Oxide (GO). More explicitly, the Improved Hummer's method was employed to synthesize GO, and subsequently which was characterized using various labortary techniques including Energy Dispersive X-Ray Spectroscopy, Fourier Transform Infrared Spectroscopy, and Raman Spectroscopy. Incorporations of 0.01%, 0.03%, and 0.05% GO by mass of cement were made in self-compacting mortars (SCMs) and their ramifications on flow, viscosity, shrinkage, mechanical properties, and microstructure in comparison to the control sample were investigated. XRD and TGA were used for phase detection of hydration products while BET Porosimetry was conducted to study the porosity of hardened mortar. Characterization for EMI shielding effectiveness of GO included cement was made on cement pastes. By incorporation of GO, the segregation resistance of SCMs increased, maximum of 57% increase in compressive strength and 48% increase in flexural strength was achieved with 0.05% inclusion of GO by mass of cement. Furthermore, EMI transmittance was reduced to a minimum of 92% through a 4 mm thick hardened cement paste sample reinforced with a maximum of 0.05% GO by mass of cement.