Research Article 2017, 2(9), 596-601 Advanced Materials Proceedings Copyright © 2017 VBRI Press 596 Self-assembling nano films on metal surface as corrosion inhibitors Susai Rajendran 1 , R Joseph Rathish 2 and S Santhana Prabha 2 1 Corrosion Research Centre, Department of Chemistry, St Antony’s College of Arts and Sciences for Women, Amala Annai Nagar, Thamaraipadi, Dindigul, Tamilnadu, 624 005, India 2 PSNA College of Engineering and Technology, Dindigul, Tamilnadu 624622, India * Corresponding author: Email: suasirajendran@gmail.com, rathishjoseph@gmail.com; Tel: +91 (0) 9443631628 Received: 30 March 2016, Revised: 02 October 2016 and Accepted: 17 April 2017 DOI: 10.5185/amp.2017/650 www.vbripress.com/amp Abstract Self-assembling molecules form protective layers on metal surfaces Self assembled nanofilms of adipic acid, N- cetyl-N,N,N-trimethyl ammonium bromide, Tween- 60, Sodium dodecyl sulphate and an aqueous extract of banana peel have been formed on the surface of carbon steel by the immersion method. The formation of the nanofilms has been confirmed by Fourier Transform Infrared spectral study and Atomic Force Microscopy Study. The corrosion inhibitive nature of the protective film has been estimated by the classical weight loss method and electrochemical study such as polarization study. The hydrophobic nature of the protective film has been investigated by measurement of contact angles of the protective films. The hydrophobic surfaces may find application in various exciting fields such as corrosion protection, raincoats, water proof surfaces and biomaterials. Copyright © 2017 VBRI Press. Keywords: Self assembling nanofilm, corrosion inhibition, hydrophobic surfaces, AFM, FTIR, contact angle measurement, hydrophobicity. Introduction Corrosion can be considered as a natural process. This spontaneous process is thermodynamically favorable. The rate of corrosion can be controlled by many methods. Use of corrosion inhibitors is one such method. These inhibitors may be classified as anodic type, cathodic type or mixed type. This classification depends on whether they control anodic reaction or cathodic reaction or both type of reactions, predominantly. A good inhibitor is expected to be water soluble and hydrophobic (to displace water from metal surface). The corrosion inhibitors should have a good delivery mechanism also. Nanotechnology is one of the hottest fields, which draws attention from all over the world and has the potential to outdate most of the technology existing today. Nanomaterials are very important because they have very special properties which may lead to new and exciting application including corrosion control [1]. Nanoparticles-based corrosion inhibitors offer better corrosion protection efficiency than the ordinary ones, because as the size of the particle decreases the surface area for a given mass and hence the number of active centers increases. Finally, this leads to efficient chemisorptions/physisorption of nanosized inhibitors on corroding metal surfaces. So, enhanced corrosion inhibition efficiency can be realized where nanoparticles/nano films are used as corrosion inhibitors. Self-assembling nanofilms can be formed on the metal surface or metal oxide surface by various techniques which include simple immersion method in a suitable solvent containing the molecules to be assembled on the metal surface. Molecules can be assembled on nickel [2- 9], which is a key component in the electronic industry and an important alloying constituent in many biometrials. Self-assembling nanofilm can be formed on copper surface [10-14] and carbon steel surfaces [15,16]. Self-assembling nanofilms have many potential applications in many areas such as non-wetting surface, corrosion inhibition, lubrication, monolayer lithography, biocompatible surfaces,etc [17-19]. Self- assembling nano layers are found to be hydrophobic and hence prevent water molecules reaching the metal surface. Hence corrosion of metals is prevented by self-assembled nano films formed on metal surface. The water repelling nature of nano layers can be compared with “Lotus Effect”, wherein water droplets rolled down the lotus leaves whereby self- cleaning effect also takes place.