Aerosol-assisted delivery of precursors for chemical vapour deposition: expanding the scope of CVD for materials fabrication

Abstract

The production of thin films of materials has become the attention of a great deal of research throughout academia and industry worldwide owing to the array of applications which utilise them, including electronic devices, gas sensors, solar cells, window coatings and catalytic systems. Whilst a number of deposition techniques are in common use, chemical vapour deposition (CVD) is an attractive process for the production of a wide range of materials due to the control it offers over film composition, coverage and uniformity, even on large scales. Conventional CVD processes can be limited, however, by the need for suitably volatile precursors. Aerosol-assisted (AA)CVD is a solution-based process which relies on the solubility of the precursor, rather than its volatility and thus vastly extends the range of potentially applicable precursors. In addition, AACVD offers extra means to control film morphology and concurrently the properties of the deposited materials. In this perspective we discuss the AACVD process, the influence of deposition conditions on film characteristics and a number of materials and applications to which AACVD has been found beneficial.

Electrocatalytic activity of CoFe2O4 thin films prepared by AACVD towards the oxygen evolution reaction in alkaline media

“…This demonstrates that CoFe 2 O 4 is an excellent candidate as a stable OER electrocatalyst in alkaline media. The AACVD CoFe 2 O 4 catalyst coatings can be easily made on different substrates providing more flexibility for using it in various device configurations [23].…”

Synthesis of superhydrophobic polymer/tungsten (VI) oxide nanocomposite thin films

“…Such superhydrophobic nanocomposite materials have already been prepared incorporating titania, Au@SiO2 (yolkand-shell), iron (II/III) oxide, cobalt oxide and nickel nanoparticles [6]. In the previous work by Crick et al, these nanocomposite coatings comprising both the superhydrophobic polymer material and the nanoparticles were deposited on glass in a single step via aerosol-assisted chemical vapour deposition [6], which has attracted attention as a deposition technique on account of its ability to deposit non-volatile material as a uniform film on a substrate [3]. However, limitations to the technique were encountered when attemptting the 'one-pot' deposition of the polymer with some species of metal-oxide nanoparticles, or with uncoated gold nanoparticles.…”

“…In recent years however, biomimetic synthetic superhydrophobic coatings have become a new breed of material which have attracted widespread attention not only for their self-cleaning capability [3], but also more recently on account of their high specific surface area, corrosion resistance, flexibility of application, resistance to bacterial adhesion and relative ease of deposition [4,5]. In particular, the deposition of polymeric superhydrophobic films has opened up the way for a new generation of smart composite materials which combine the benefits of both superhydrophobic and nanocomposite factors by incorporation of functional nanoparticles into the polymer's microstructure.…”

Chemical Vapour Deposition of Gas Sensitive Metal Oxides

“…Typically, liquid precursors are used in order to generate sufficient vapour pressure when heated to intermediate temperature (<200˝C) with mixing of multiple precursor streams used to produce complex mixtures. Variants on this system such as liquid injection-and aerosol assisted-(AA)CVD [12] are typically used to introduce low volatility/solid precursors, with precursor evaporation only occurring inside the CVD reactor, although they also afford great opportunities in synthesizing doped or ternary/quaternary materials due to the relative ease of controlling stoichiometry through the precursor solution.…”