Chemical Vapour Deposition (CVD) Technique for Abatement of Volatile Organic Compounds (VOCs)

Abstract

Chemical vapour deposition (CVD) is an important technique that uses volatile precursors to produce thin film deposits on an exposed substrate, having the capability to generate different types of nanostructures (e.g. nanoparticles, nanotubes, nanofibers or nanocomposites) as catalytic materials. The environmental hazard of volatile organic compounds (VOCs) requires efficient methods to reduce their emission into the atmosphere, due to their high potential to cause severe health issues, along with their extended spread in the environment. Catalytic combustion proves to be one of the most effective means for the abatement of VOCs, employing different catalysts, such as noble metals or non-noble metal oxides, to facilitate the oxidation process of the pollutants. These catalysts can be prepared through various methods as multiple steps wet processes or CVD techniques, indicating the superiority of the CVD-prepared catalysts compared to those prepared using the former type of process, due to the ability to achieve high dispersion of the active material, together with enhanced textural and morphological properties. This paper aims to present the various CVD techniques employed in the fabrication of different catalysts with the possibility of generating materials at nano-scale for use in numerous reactions, mostly in combustion process for VOCs decomposition.

Techniques of Preparation of Thin Films: Catalytic Combustion

“…In light of these findings, Bahlawane et al deposited thin films of cobalt oxide onto stainless steel slices, using chemical vapor deposition (CVD) with cobalt (II) acetylacetonate as precursor [199]. CVD is a versatile process which allows the facile preparation of numerous catalytic materials, inducing special crystalline morphologies, high surface areas for the solids or material gradient in the deposited layer [202]. The Co 3 O 4 film was produced as a cubic spinel-type with a crystalline size of 30-40 nm with a thickness layer of ~300 nm.…”

The catalytic activity of manganese oxide catalysts for the toluene oxidation process

“…Volatile organic compounds (VOCs) are one of the environmental pollutants of concern because they contribute to polluted environmental phenomena such as photochemical smog and secondary particulate matter. Moreover, some VOC emitted from artificial activities seriously affects human health and the environment [1][2][3][4][5][6][7][8][9][10].…”

Comparative kinetics study of the catalytic oxidation of benzene and its mono-halogenated derivatives over V 2 O 5 –WO 3 /TiOLazar1, Koeser2, Balasanian3 2022Comptes Rendus. ChimieSelf Cite

“…The emissions of VOCs can be controlled using methods based on recovery and destruction [2,3,11,12]. Several traditional technologies, such as adsorption at low concentration and thermal oxidation for high concentration, have been employed to removing VOCs from emission with many advantages and limitations [6,7,[13][14][15]. Catalytic oxidation has been evidenced to be one of the most reliable and suitable technology for the post-treatment emissions at low aromatic or non-aromatic VOCs concentration [3,12,16,17].…”