, J. R. (2014). Photo-initiated chemical vapor deposition of thin films using syngas for the functionalization of surfaces at room temperature and near-atmospheric pressure. Surface and Coatings Technology, 244, p. 98-108. doi:10.1016/j.surfcoat.2014 This study addresses the current limiting factor, namely the cost issue, by using simple gas precursors, using an a↵ordable initiation source and operating under normal condition. This approach di↵ers from the current approaches which use expensive solvents as precursors, energy consuming-sources of initiation (e.g.high temperature, plasma and VUV) and operate under high vacuum and/or high temperatures. While the current paradigm is to target the peak absorption of a molecule, the present study indicates that long chain polymerized products can be formed from o↵-peak wavelength. It has been found that photo-initiated deposition occurs and that a wide range of water contact angles, from 5 to 118 , can be obtained by manipulating the experimental conditions. A multilinear empirical model has been derived, and it predicts fairly well the contact angles obtained as a function of the di↵erent experimental parameters.

Cellulose nanocrystals (CNCs) are novel nanomaterials produced by the pulp and paper industry. The surface properties of CNCs are key factors for their dispersion in solvents. These polar materials disperse readily in water, but not in organic solvents. The ability to disperse into typically non-polar organic matrices is an indispensable requirement to exploit the growing market for nanocomposite materials. We present an innovative approach for modifying the surface of CNCs through scalable, gas-phase photo-initiated chemical vapour deposition (PICVD). Using syngas as a treatment precursor, we demonstrate the effectiveness of this technique to render the surface of the CNCs compatible with mildly polar and non-polar solvents, evidenced by contact angle measurements. Further proof of this successful modification is given through dispersion assays, showing for example the ability to disperse treated CNC in toluene (whereas untreated samples do not disperse). Suspensions in organic solvents remain stable in excess of two weeks. Chemical characterization through XPS and FTIR confirms the presence of an oxygen-containing coating on the CNC surface.

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7While nanoparticles have been the focus of intensive research for several years as a result of their 8 remarkable surface-driven properties, they remain, for the most part, stuck in the lab. This unfortunate 9 fact can be explained by three main reasons: (1) most studies have not dealt with the scalability and cost 10 issues related to the use of nanomaterials on an industrial scale; (2) a great deal of focus has been applied 11 to "outlier" results that promise far more than can be delivered; and (3) very little attention has been given 12 to surface engineering. We propose to curtail the significant cost issue by extracting low-cost, low-grade 13 nanoparticles that are appropriate for several applications from a ubiquitous and abundant feed stock: fly 14 ash from municipal solid waste (MSW) incineration. The novel technique we apply is capable of both 15 extraction and functionalization of the nanoparticles present in this undervalued waste stream using 16 photo-initiated chemical vapor deposition (PICVD). By setting functionalization conditions to favor 17hydrophilic surface properties, the treated ash can readily be dispersed in a polar solvent such as water: 18 larger particulates then settle out of suspension, while the lighter nanoparticles remain in the supernatant 19 and are ready for use. While it is true that this method yields low-grade nanoparticles (polydisperse and 20 multi-composite), these can be used in a variety of applications where composition is less crucial, such as 21 increasing the thermal conductivity of composites and nanofluids. 22

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