Graphene oxide reinforced high surface area silica aerogels Saoirse Dervin a,b , Yvonne Lang a,c , Tatiana Perova d,e , Steven H. Hinder f , Suresh C. Pillai a,b, ⁎ a Nanotechnology & Bio-Engineering Research Group, Department of Environmental Science, School of Science, Institute of Technology Sligo, Ash Lane, Sligo, Ireland b Centre for Precision Engineering, Materials and Manufacturing Research (PEM), Institute of Technology Sligo, Ash Lane, Sligo, Ireland c CERIS, School of Science, Institute of Technology Sligo, Sligo, Ireland d Department of Electronic and Electrical Engineering, Trinity College Dublin, Dublin 2, Ireland e ITMO University, 49 Kronverkskiy pr., Saint Petersburg, Russia f The Surface Analysis Laboratory, Faculty of Engineering & Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK abstract article info Article history: Received 7 February 2017 Received in revised form 16 March 2017 Accepted 20 March 2017 Available online xxxx Silica aerogel structures were intercalated with graphene oxide (GO) via the addition of GO to the colloidal silica sol and subsequent sol–gel polymerization. The potential of GO to act as a nanofiller, for ambient pressure dried, hydrophobic silica aerogels, was systematically investigated. The influences of 0 to 2 wt% GO loadings, on the physical properties of silica aerogels, were analysed by examining the bulk density, volume shrinkage (%), pore volume and surface area of the composite aerogels. Additionally, the chemical composition of the composite gels was determined using FTIR, Raman, XRD and XPS. The study revealed that a GO addition of as little as 0.5 wt% is capable of supporting the porous framework of silica aerogels and also enhancing the properties of the gels simultaneously. The additions of 0.5 wt% GO increased the surface area and pore volume of the aerogel from 390 to 700 m 2 /g and 0.59 to 0.99 cm 3 , respectively, and decreased aerogel density from 0.19 to 0.14 g/cm 3 . The investigation therefore revealed that intercalation of the silica aerogel matrix with small quantities of GO can inhibit volume shrinkage during drying without hindering the physical properties of silica aerogels. © 2017 Elsevier B.V. All rights reserved. Keywords: Graphene Graphene oxide Silica Aerogel 1. Introduction The remarkable features of silica aerogels including ultralow density (~0.003 g/cm 3 ), high specific surface area (500 m 2 /g to 1200 m 2 /g), high porosity (80–99.8%), high thermal insulation values (0.005 W/mK) and versatility have resulted in their application in a number of industrial fields including aerospace, ultrasonic sensing, gas sensing, waste removal, optics, energy storage, catalysis and insulation [1–3]. Traditionally silica aerogels were prepared via supercritical drying [4–6]. This route uses supercritical fluids, elevated temperature and pressure to remove the liquid component of a gel, in the absence of cap- illary stress and surface tension. Though once a favoured method, this technique is expensive, time consuming and often hazardous, rendering the process impractical for industrial use. In order to exploit aerogels commercially, cost effective drying routes are required. Consequently, many upsurges in aerogel research have focused on the determination of alternative preparation routes [7–23]. In recent times, ambient pressure drying (APD) of sodium silicate gels has been identified as a feasible approach for the production of sil- ica aerogels [24,25]. This method, however, often yields fragile gels [26]. Solvent extraction under atmospheric pressure evokes lateral compres- sive stress amongst the gel network in order to redress the loss of pore liquid during drying [27]. Polar Si–OH functionalities, located on the sur- face of the gels, interact with adjacent chains and give rise to relentless condensation reactions, which continue after complete formation of the silica network [27,28]. The interaction between the subsequent surface silanol groups has an elastic effect on the inner surfaces of the porous walls comprising the gel network [29]. The adjoining walls of the pores are drawn towards one another and eventually cause the porous network to collapse [29]. This results in irreversible shrinkage of the aerogel network [28,29]. The consequential innate brittleness of the sil- ica network often limits extensive application of these materials. Ac- cordingly, the mechanical properties of the interconnected silica network must be improved for commercial applications. Several measures to enhance the mechanical properties and circum- vent shrinkage of the aerogel network have been explored [30]. Surface modification or silylation, is one technique which has proved effective in preparing mechanically amended silica aerogels [14]. The process uses organosilanes such as hexamethyldisiloxane (HMDSO), hexamethyldisilazane (HMDZ), methyltriethoxy-silane (MTES) and trimethylchlorosilane (TMCS), converting Si–OH functionalities into Journal of Non-Crystalline Solids xxx (2017) xxx–xxx ⁎ Corresponding author at: Nanotechnology & Bio-Engineering Research Group, Department of Environmental Science, School of Science, Institute of Technology Sligo, Ash Lane, Sligo, Ireland. E-mail address: pillai.suresh@itsligo.ie (S.C. Pillai). NOC-18254; No of Pages 8 http://dx.doi.org/10.1016/j.jnoncrysol.2017.03.030 0022-3093/© 2017 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Journal of Non-Crystalline Solids journal homepage: www.elsevier.com/locate/jnoncrysol Please cite this article as: S. Dervin, et al., Graphene oxide reinforced high surface area silica aerogels, J. Non-Cryst. Solids (2017), http://dx.doi.org/ 10.1016/j.jnoncrysol.2017.03.030