New Sol-Gel Synthesis of Ordered Nanostructured Doped ZnO Films

TL;DR

This paper introduces a new sol-gel method for synthesizing highly ordered, doped ZnO films with controlled orientation and nanostructure, suitable for advanced optoelectronic applications.

Contribution

It presents a novel sol-gel synthesis route for producing highly ordered, doped ZnO films with specific crystallographic orientations and nanostructures, including Co, Fe, Mn, and V doping.

Findings

High structural order and uniaxial crystallite orientation achieved.

Cobalt doping leads to columnar nanocrystals.

Vanadium doping results in formation of ZnAl2O4 spinel oxide.

Abstract

A novel sol-gel route to c-axis orientated undoped and Co, Fe, Mn and V doped ZnO films is reported. Sols were prepared from a hydrated zinc acetate precursor and dimethyl formamide (DMF) solvent. Films were spin-coated on to hydrophilic sapphire substrates then dried, annealed and post-annealed, producing almost purely uniaxial ZnO crystallites and a high degree of long-range structural order. Specific orientation of hexagonal crystallites is demonstrated both perpendicular and parallel to the substrate surface. Cobalt doping resulted in the formation of columnar ZnO nanocrystals. Vanadium doped films formed the spinel oxide ZnAl2O4, resulting from the reaction between ZnO and the sapphire substrate. Structural, optical and morphological characterisation demonstrated the high quality of the films.