Structural evolution, optoelectrical and corrosion properties of electrodeposited WO 3 integration on Zn-TiO 2 electrolyte for defence super application A.A. Daniyan a, * , L.E. Umoru a , O.S.I. Fayomi b, c , A.P.I. Popoola b a Department of Materials Science and Engineering, Obafemi Awolowo University, Ile-Ife, Nigeria b Department of Chemical, Metallurgical and Materials Engineering, Tshwane University of Technology, P.M.B. X680, Pretoria, South Africa c Department of Mechanical Engineering, Covenant University, P.M.B 1023, Ota, Ogun State, Nigeria article info Article history: Received 15 March 2018 Received in revised form 20 June 2018 Accepted 25 June 2018 Available online xxx Keywords: Nano-composite Electrocodeposition Corrosion Conductivity and resistance abstract Multifunctional nano composite coatings of Zn-TiO 2 -WO 3 were deposited electrolytically on mild steel (MS) from Zn bath, having Zn 2þ ions and uniform dispersion of TiO 2 and WO 3 nano particulates. The electrical, optical and corrosion resistance characteristics of the electrocodeposited coatings were assessed by Keithley 2400 Series Source meter with Multimeters, Newport Solar Simulator and a PGSTAT30 Autolab potentiostat respectively. The morphological characteristics of the composite coatings were characterized by scanning electron microscope (SEM) equipped with energy dispersive spec- trometer (EDS). The result revealed that the electrocodeposits showed good stability and Zn-TiO 2 -WO 3 nanocomposite deposits displayed enhanced microstructural qualities, good electrical conductivity and exhibited enriched corrosion resistance. © 2018 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/). 1. Introduction Metal oxides displayed many important physical and chemical properties in which many of them are semiconductors with large bandgap compounds of conductivity which is n-type. For instance, WO 3 and TiO 2 have bandgaps in the range between 3.0e3.4 eV [1e3]. WO 3 and TiO 2 and are two metal oxides with related con- ducting properties. Recently, great attentions are now drawn to mixed oxides, ever since, it has been established that mixed com- pounds of TiO 2 /WO 3 enhanced electrical charge separation observed under illumination, which has been verified with diverse systems [4,5] and it has been revealed that TiO 2 -WO 3 mixed com- pound found applications in varistor with an electrical behaviour that is not mere linear [6]. Electrocodeposition provides a suitable and multipurpose way to the synthesis of composites of many metal with inorganic oxides [7 ,8] including Metal with WO 3 [9] and metal with TiO 2 [10]. Currently, there is wide interest in composite coatings comprising TiO 2 and WO 3 in optoelectrical applications. For instance, a greater photo-response was experienced when bilayered composite of TiO 2 and WO 3 coatings, compared to the single-component films of each of the constituents [11 , 12]. It has been observed that the photo- catalytic activity of TiO 2 - WO 3 coatings was found to triple that of pure TiO 2 coatings in oxidation applications [13]. An electron pool observed when WO 3 was coupled with TiO 2 coating in the con- struction of a sensitive PECAS (photoelectrochemical anticorrosion system) with in-built energy storage ability [14]. Apart from the fact that combination of TiO 2 and WO 3 is a great asset in the design of photoelectrochromic devices [15], It has also been established that TiO 2 and WO 3 possess electrochromic prop- erties that are complementary to each other [16]. Nevertheless Nanostructured TiO 2 - WO 3 coatings have now be discovered to displayed more excellent electrochromic and photoelectrochemical properties compared to the bulk of their particles, because they can be brilliantly controlled by adjusting the particle size and some electrocodeposition parameters for coatings, Therefore, this work studied the Structural Evolution, Opto electrical and Corrosion Properties of Electrocodeposited composite of nanostructured TiO 2 and WO 3 in Zn matrix for the purpose of developing advance active coating for engineering applications. The focus of this study is the optimization of the WO 3 nanoparticulates on Zn-TiO 2 * Corresponding author. E-mail addresses: daniyan03@gmail.com (A.A. Daniyan), ojosundayfayomi3@ gmail.com (O.S.I. Fayomi). Peer review under responsibility of China Ordnance Society Contents lists available at ScienceDirect Defence Technology journal homepage: www.elsevier.com/locate/dt https://doi.org/10.1016/j.dt.2018.06.015 2214-9147/© 2018 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Defence Technology xxx (2018) 1e7 Please cite this article in press as: Daniyan AA, et al., Structural evolution, optoelectrical and corrosion properties of electrodeposited WO 3 integration on Zn-TiO 2 electrolyte for defence super application, Defence Technology (2018), https://doi.org/10.1016/j.dt.2018.06.015