Synthesis of NiO nanoparticles by hydrothermal method: Optical and surface area studies

A.G. Al-Sehemi, A.S. Al-Shihri, A. Kalam and G. Du
King Khalid University, SA

Keywords: nickel oxide nanoparticles, chemical method, X-ray diffraction, electron microscopy, optical properties, surface area studies

Summary:

Nanostructured NiO is a very important p–type semiconductor with a stable wide band gap (3.6–4.0 eV)], which has also aroused considerable attention due to its practical and potential applications in various fields such as catalysis, magnetic materials, super capacitors, gas sensor, electro–chromic devices, dye–sensitized solar cells, optical materials and also as water treatment adsorbents.We have demonstrated a simple and template-free hydrothermal calcination method for the synthesis of NiO nanoparticles by using Ni(NO3)2∙6H2O, HMT and NaOH as the starting materials. SEM studies revealed that the synthesized nickel oxide nanoparticles showed spherical morphologies and the morphologies can be easily tailored by adjusting the pH value. By means of the investigations, it is found that as the pH increases optical band gap energy and specific surface area also increases. It revealed that the pH value of the solution significantly affected the particle size, optical band gap energy and surface area of the synthesized NiO nanoparticles