Optical and electrical behaviors in NiO/xFe 2 O 3 nanoparticles synthesized by microwave irradiation method M. Rashad a, b, * , Taymour A. Hamdalla a, c , S.E. Al Garni d , A.A.A. Darwish a, e , S.M. Seleim f a Nanotechnology Research Laboratory, Department of Physics, Faculty of Science, University of Tabuk, Tabuk, Saudi Arabia b Department of Physics, Faculty of Science, Assiut University, Assiut, Egypt c Department of Physics, Faculty of Science, Alexandria University, Alexandria, Egypt d Department of Physics, Faculty of Science Al Faisaliah, King Abdulaziz University, Jeddah, Saudi Arabia e Department of Physics, Faculty of Education at Al-Mahweet, Sana'a University, Al-Mahwit, Yemen f Department of chemistry, Faculty of Science, Alexandria University, Alexandria, Egypt article info Article history: Received 16 May 2017 Received in revised form 16 November 2017 Accepted 1 December 2017 Keywords: NiO/xFe 2 O 3 Nanoparticles Metal oxide Optical properties abstract NiO/xFe 2 O 3 nanoparticles (NPs) with different Fe 2 O 3 content of (x ¼ 0.0, 0.3, 0.5 and 1) have been synthesized by microwave irradiation method. For more investigations, the solution of these NPs have been dropped on top of the glass substrate. The prepared films of the synthesized materials have been characterized by elemental analysis such as X-ray diffraction and Transmission electron microscope. An analysis of the phase composition and microstructure shows that Fe 2 O 3 content has slightly influence on the crystal structure and morphology of NiO NPs, which reveals that the addition of Fe 2 O 3 NPs has been incorporated into the NiO host lattice. A comparison between Fe 2 O 3 and NiO NPs have been done using these analyses. The effect of Fe 2 O 3 addition content in NiO lattice on the linear and nonlinear optical properties have been studied. The refractive index and the energy gap have been decreased by about 24% and 12.5% respectively with increasing Fe 2 O 3 NPs contents. The improving optical conductivity of assembled films is verified due to the addition of Fe 2 O 3 NPs. © 2017 Elsevier B.V. All rights reserved. 1. Introduction Nanostructured materials have attracted many groups of re- searchers due to their unique optical and electrical properties. These properties have emerged as a result of the success in decreasing the dimensions of material to be in the nanoscale [1]. The metal oxides have a prominent role in different areas of science especially in material science [2-4]. The metal oxides widely used as gas sensors [5], electric circuits [6], catalysis for oxygen re- ductions [7]. These properties have changed completely when the metal oxides fabricated in the nanoscale due to its increase in the edge density and its tiny size [8]. The edge density of the monoxides metals will cause a high energy surface while the small size will affect the internal structure and the lattice symmetry and cell pa- rameters. Alloying of two semiconductors at the nanometer scale produces materials that display properties distinct not only from the properties of their bulk counterparts but also from those of their parent semiconductors [9]. The recent generations of Li-ion battery need energy with higher density, large capacity, higher temperature operation, etc… [10]. The new generation storage mechanism in the Li-ion batteries is based on the nano metal oxides in the anode materials [11]. The addition of Fe 2 O 3 nanoparticles (NPs) to the NiO NPs will have high potential applications, espe- cially in the Li-ion batteries. The metal oxides have high capacity and excellent cycling about three times larger than those of graphite [12]. Therefore, due to their industrial and technological applications, we intend to study in the work the effect of adding Fe 2 O 3 NPs by different content to NiO NPs to form NiO/xFe 2 O 3 NPs with (x ¼ 0.0, 0.3, 0.5 and 1). On the basis of the structural change, the optical and electrical properties of the fabricated samples will be explained. In the future, we believe that our synthesized samples will be helpful in developing the anode of the Li-ion batteries for their easy and inexpensive fabrication. 2. Experiment technique A microwave oven with 650 W (Sanle general electric corp. * Corresponding author. Nanotechnology Research Laboratory, Department of Physics, Faculty of Science, University of Tabuk, Tabuk, Saudi Arabia. E-mail address: mohamed.ahmed24@science.au.edu.eg (M. Rashad). Contents lists available at ScienceDirect Optical Materials journal homepage: www.elsevier.com/locate/optmat https://doi.org/10.1016/j.optmat.2017.12.002 0925-3467/© 2017 Elsevier B.V. All rights reserved. Optical Materials 75 (2018) 869e874