Novel controlled synthesis of nanoporous carbon nanorods from resorcinol-formaldehyde xerogels Ahmed Awadallah-F 1 , Shaheen A. Al-Muhtaseb ⇑ Department of Chemical Engineering, Qatar University, PO Box 2713, Doha, Qatar article info Article history: Received 2 April 2017 Received in revised form 27 April 2017 Accepted 2 May 2017 Available online 4 May 2017 Keywords: Carbon materials Carbon nanorods Sol-gel preparation Porous materials Resorcinols Formaldehydes abstract A novel approach is discovered to produce carbon nanorods (CNRs) from resorcinol-formaldehyde xerogels. The structure and morphology of CNRs are characterized by pore size analysis, nano- scanning electron microscopy, elemental analyses and Raman spectra, FTIR spectroscopy. CNRs exhibited diameter ranges from 262 to 327 nm and lengths of up to several microns. The growth rate of CNRs depends fundamentally on the gelation temperature. CNRs’ structures exhibits nanopores with average pore sizes of 2.39 and 1.64 nm for CNRs produced from xerogels glated at 70 and 85 °C, respectively. It is anticipated for CNRs to open new gates for advanced nano-device applications. Ó 2017 Elsevier B.V. All rights reserved. 1. Introduction Since the discovery of carbon nanotubes (CNTs) [1], much attention has been focused on one dimensional (1D) nanostruc- tures like nanotubes and nanowires because of their fundamental importance and their anticipated wide range of applications in nano-devices that would enhance human’s life [2]. CNRs have two advantages over CNTs. Firstly, the properties of CNRs can be controlled more precisely by either manipulating the synthesis conditions or using a doping techniques. Secondly, the native oxide layer that can be formed on the outside of CNRs allows the appli- cation of a broad range of already well developed functionalization and blocking chemistries [3]. Although numerous techniques have been developed for the fabrication of CNTs and 1D nanomaterials, the exploration of new methods and controllable synthesis of 1D nanostructures under ambient conditions is still an interesting and challenging topic [1,4–6]. Generally, such kind of nanostructures could be prepared by two methods. The first method is by a ‘‘bottom-up” approach, where the self-assembly of small sized structures build into larger structures. The other method is a by ‘‘top-down” approach, where large structures are reduced down into smaller sizes to produce nanoscale structures [7]. Several methods were developed for the fabrication of nano-rod or nano-wire arrays, including catalytic growth, template [8], Langmuir Blodgett method and electrospin- ning [9]. Nonetheless, all these methods are not practical in mass production and are expensive. The motivation for this study comes from the difficult chal- lenges of the above-mentioned synthesis processes to produce CNRs. In this work [10], CNRs are prepared from the polymeriza- tion of resorcinol and formaldehyde in presence of sodium carbon- ate, followed by atmospheric drying, carbonization and activation [11]. This novel method of synthesizing CNRs can provide a large scale and controllable route to provide a low cost supply for raw nanowires and their corresponding nano-devices. 2. Materials and methods Resorcinol (99.98%, Alfa Aesar), formaldehyde (37 wt%, Aldrich), sodium carbonate (anhydrous, Fisher) and acetone (99.6%, Fisher) were used as received. Other reagents are analytical grade. Resor- cinol–formaldehyde (RF) xerogels have been prepared with a resorcinol-to-formaldehyde molar ratio of 0.3; a resorcinol-to- water molar ratio of 0.05; a resorcinol-to-catalyst molar ratio of 50; and an initial solution pH of 7. RF solutions were poured into polypropylene vials, sealed and placed in an oven 7 days [12]. Oven temperatures were set at 70 °C and 85 °C for the consequent acti- vated carbons denoted as RF-ACX-1 and RF-ACX-2, respectively. Other details of xerogels‘ synthesis, carbonization and activation, http://dx.doi.org/10.1016/j.matlet.2017.05.021 0167-577X/Ó 2017 Elsevier B.V. All rights reserved. ⇑ Corresponding author. E-mail address: s.almuhtaseb@qu.edu.qa (S.A. Al-Muhtaseb). 1 Dr. A. Awadallah-F is on leave the Radiation Research of Polymer Department, National Centre for Radiation Research and Technology, Atomic Energy Authority, P.O. Box 29, Nasr City, Cairo, Egypt. Materials Letters 201 (2017) 181–184 Contents lists available at ScienceDirect Materials Letters journal homepage: www.elsevier.com/locate/mlblue