Preparation, Microstructure and Optical Absorption Behaviour of NiO Thin Films

$113.00 plus tax (Refund Policy)

Buy Article:

Abstract:

Nickel oxide thin films have been prepared by spin coating on glass, silicon(111) and quartz substrate using a solution of nickel acetate tetrahydrate in 2-methoxyethanol and mono-ethanolamine and subsequent annealing at 300–600 °C for 2 h in air. These films have been characterized with regard to phase, microstructure and optical absorption using X-ray diffraction, atomic force microscopy and UV-visible spectrophotometry, respectively. It is shown that NiO thin films have polycrystalline nature and possess an f.c.c. (NaCl-type) structure with lattice parameter varying with annealing temperature (T) and solution molarity; typical value being a = 4.186 Å with T = 500 °C and molarity 0.5 M. The microstructure clearly reveals the formation of ellipsoids with average projected major and minor diameters as ∼58 and ∼38 nm, respectively and nano-rods of average diameter ∼12nm with aspect ratio of ∼5.2. On the other hand, thin films formed by dip coating with the same solution contain spherical particles of average diameter ∼28 nm. NiO thin films exhibit (i) high optical transmittance (80–95%) in the wave length range of 400–800 nm, (ii) sharp absorption in the interval 300–400 nm like that of semiconductor/insulator, (iii) decrease of energy band gap, Eg (value lies in the range 3.66–3.83 eV; bulk value being 3.55 eV) with increase of annealing temperature and molarity both. The higher values of band gap have been attributed to the reduced average size of the crystallites.

Keywords: DIP COATING; NANO-PARTICLES; NANO-RODS; QUANTUM SIZE EFFECTS; SPIN COATING; THIN FILMS

Document Type: Research Article

DOI: http://dx.doi.org/10.1166/jnn.2008.AN36

Publication date: August 1, 2008

More about this publication?
  • Journal for Nanoscience and Nanotechnology (JNN) is an international and multidisciplinary peer-reviewed journal with a wide-ranging coverage, consolidating research activities in all areas of nanoscience and nanotechnology into a single and unique reference source. JNN is the first cross-disciplinary journal to publish original full research articles, rapid communications of important new scientific and technological findings, timely state-of-the-art reviews with author's photo and short biography, and current research news encompassing the fundamental and applied research in all disciplines of science, engineering and medicine.
  • Editorial Board
  • Information for Authors
  • Subscribe to this Title
  • Terms & Conditions
  • ingentaconnect is not responsible for the content or availability of external websites
Related content

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more