Poly (methyl methacrylate) (PMMA) is a thermoplastic synthetic polymer, which displays superior characteristics such as transparency, good tensile strength, and processability. Its performance can be improved by surface engineering via the use of functionalized thin film coatings, resulting in its versatility across a host of applications including, energy harvesting, dielectric layers and water purification. Modification of the PMMA surface can be achieved by atomic layer deposition (ALD), a vapor-phase, chemical deposition technique, which permits atomic-level control. However, PMMA presents a challenge for ALD due to its lack of active surface sites, necessary for gas precursor reaction, nucleation, and subsequent growth. The purpose of this review is to discuss the research related to the employment of PMMA as either a substrate, support, or masking layer over a range of ALD thin film growth techniques, namely, thermal, plasma-enhanced, and area-selective atomic layer deposition. It also highlights applications in the selected fields of flexible electronics, biomaterials, sensing, and photocatalysis, and underscores relevant characterization techniques. Further, it concludes with a prospective view of the role of ALD in PMMA processing.

Vertically aligned carbon nanotubes (VACNTs) were grown directly on a pretreated Inconel® metallic substrate by thermal chemical vapor deposition without the need of catalyst addition. This experimental approach allows the substrate surface to act as both the catalyst and support for the CNTs growth therefore enhancing the connection between the two. It was found that uniformly dispersed and densely packed nano-sized, intrinsic catalytic particles, generated during the annealing pretreatment, allow the growth of the vertically aligned CNTs. Scanning electron microscopy, transmission electron microscopy and Raman spectroscopy were used to assess the quality and the nature of the formed CNTs.Electrochemical measurements were performed to evaluate the possibility to use the Inconel/VACNTs system as an electrode material. As a proof of concept, the capacitive behavior of the VACNTs arrays coupled to the Inconel substrate as the active electrode material and the current collector, respectively, in supercapacitors is demonstrated.

Amorphous or anatase crystalline TiO2/VA-CNT nanocomposites were grown controlling the synthesis temperature. Photocatalytic degradation of RhB of 55% was achieved after 240 min. The immobilized material remains active after 4 cycles of use.

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Tin dioxide thin films are grown at low-moderate temperature using a non-hydrolytic atomic layer deposition process. Granular SnO2 thin films are obtained from tin(IV) tetra-butoxide reacting with acetic acid, at temperatures as low as 75 °C. Influence of pulse length of both reactants and of the deposition temperature on the saturation is studied. A narrow ALD window is established between 150 and 175 °C with a growth per cycle of 0.07 nm and with a linear growth as a function of the number of cycles. Above 200 °C decomposition of the tin precursor is not negligible. Microstructure and morphology of the as-prepared films as well as the influence of the deposition parameters are investigated using electron and atomic force microscopies. The band gap of the obtained films is determined using UV-visible spectroscopy. Finally the use of the SnO2 coated carbon nanotubes as gas sensing layer is discussed.