CNTs modified ZnO and TiO₂ thin films: The effect of loading rate on band offset at metal / semiconductor interfaces

¹ Engineering and Applied Physics Team (EAPT), Sultan Moulay Slimane University, Beni Mellal, Morocco
² University of Mohammed 5 th — Rabat, Morocco
³ Laboratory of engineering in chemistry and physics of material, Faculty of Sciences and Technology, Beni-Mellal, Morocco
⁴ Applied Chemistry Team, Faculty of Sciences and Techniques of Al Hoceima, Abdelmalek Essaadi University, Al Hoceima, Morocco
⁵ Molecular Electrochemistry and Inorganic Materials Team, Beni Mellal, Faculty of Science and Technology, Sultan Moulay Slimane University, Morocco
⁶ Thermodynamics, Mechanics and Energetics: Experimentation, Modeling and Simulation: TMEEMS, Physical Department, Faculty of Sciences, Mohammed 5 th University, Av Ibn Battouta, PO Box 1014, Rabat 10000, Morocco

^* Corresponding author: ziat.estbm@gmail.com;
^** mar.hammi@yahoo.com;
^*** belkhanchihamza@gmail.com;
^**** ousama.if@gmail.com

Abstract

ZnO and TiO₂ are direct wide band gap semiconductors with intriguing properties. A wide range of applications makes it one of the most studied materials in the past decade, particularly when elaborated as nanostructures. In this work, we focus on synthesis of CNTs modified ZnO and TiO₂ thin films using sol-gel method. The morphological and optical characterizations of the based ZnO and TiO₂ films were carried out using scanning and transmission electron microscopy (SEM and TEM), XRD and UV spectroscopy. Electrical properties of the deposited ZnO/CNTs and CNTs /TiO₂ were studied using I-V measurements at room temperature in metal/semiconductor/metal configuration, by the use of an array of metallic micro-electrodes deposited on the surface of the elaborated thin films. This allows determining qualitatively the electrical conductivity of thin films and the different parameters of the Schottky junction between the composites nano-films and the substrate. This study is necessary for future applications in solar cell.