Research Article Effect of Zirconium Oxide Nanofiller and Dibutyl Phthalate Plasticizer on Ionic Conductivity and Optical Properties of Solid Polymer Electrolyte Siti Mariah Mohd Yasin, Suriani Ibrahim, and Mohd Rafie Johan Nanomaterials Engineering Research Group, Advanced Materials Research Laboratory, Department of Mechanical Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia Correspondence should be addressed to Mohd Raie Johan; mraiej@um.edu.my Received 23 April 2014; Revised 17 June 2014; Accepted 26 June 2014; Published 15 July 2014 Academic Editor: Josias Hamman Copyright © 2014 Siti Mariah Mohd Yasin et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. New solid polymer electrolytes (SPE) based on poly(ethylene oxide) (PEO) doped with lithium triluoromethanesulfonate (LiCF 3 SO 3 ), dibutyl phthalate (DBP) plasticizer, and zirconium oxide (ZrO 2 ) nanoparticles were prepared by solution-casting technique. he conductivity was enhanced by addition of dibutyl phthalate (DBP) plasticizer and ZrO 2 nanoiller with maximum conductivity (1.38 × 10 −4 Scm −1 ). he absorption edge and band gap values showed decreases upon addition of LiSO 3 CF 3 , DBP, and ZrO 2 due to the formation of localized states in the SPE and the degree of disorder in the ilms increased. 1. Introduction Nowadays, the need for smaller, lighter, higher capacity, and energy density devices are tremendous especially in the ield of polymer electrolytes materials. Extensive studies were conducted on solid polymer electrolytes (SPE) as new ionic conductors to replace the conventional electrolytic solutions [1]. It is believed that the electrolytic solutions have solution leakage, electrode corrosion, contamination, and solute seeping. SPE based on poly(ethylene oxide) (PEO) have received much attention due to its well-dissolved salts and such electrolytes possess proper chemical structures to support the ion transport [2]. Many researchers discovered that these polymer electrolytes have low conductivities [3]. Neverthe- less, they realized that polymer electrolytes have a big poten- tial for future technology development. Since then, more investigations had been carried out to overcome the problem like the reduction of the PEO crystalline phase which is known to be contributed to its lower conductivity [4]. In that regard, addition of low molecular weight plasticizer into the polymer electrolytes systems will enhance the conductivity [5]. he plasticization is the conventional way to reduce the crystallinity and enhances the amorphous phase content of the polymer electrolytes. hus, it increases the lexibility in the polymeric segments and produces mobile charge carriers due to ion dissolution efect. In this work, dibutyl phthalate (DBP) was used as a plasticizer. his leads to high ambient conductivity. DBP plasticizer contributed higher ionic conductivity compared to ethylene carbonate (EC) and polycarbonate (PC) plasticizers. For example at room temperature, electrolyte system with DBP [6] as a plasticizer contributes to 10 −4 S/cm compared to EC/PC [7, 8] with 10 −6 S/cm. However the conductivity enhancement occurred at the expense of SPE mechanical properties. To overcome this, the addition of nanosize ceramic illers into the SPE system results in the increase of ionic conductivity coupled with its mechanical properties [9]. In this work, zirconium oxide (ZrO 2 ) nanoparticles were used as ceramic iller into the host polymer matrix [10, 11]. he conductivity increases with decrease in particle size (nanometer), that is, increase in the ratio of surface area to volume, thus leading to an increasing dominance of the atomic behavior on the surface of particle compared to the dominance of the atomic behaviors in the Hindawi Publishing Corporation e Scientific World Journal Volume 2014, Article ID 547076, 8 pages http://dx.doi.org/10.1155/2014/547076