In this paper, polyethyleneterephthalate (PET) films with and without plasma pretreatment were modified by atomic layer deposition (ALD) and plasma-assisted atomic layer deposition (PA-ALD). It demonstrates that the Al₂O₃ films are successfully deposited onto the surface of PET films. The cracks formed on the deposited Al₂O₃ films in the ALD, plasma pretreated ALD, and PA-ALD were attributed to the energetic ion bombardment in plasmas. The surface wettability in terms of water contact angle shows that the deposited Al₂O₃ layer can enhance the wetting property of modified PET surface. Further characterizations of the Al₂O₃ films suggest that the elevated density of hydroxyl -OH group improve the initial growth of ALD deposition. Chemical composition of the Al₂O₃-coated PET film was characterized by X-ray photoelectron spectroscopy, which shows that the content of C 1s reduces with the growing of O 1s in the Al₂O₃-coated PET films, and the introduction of plasma in the ALD process helps the normal growth of Al₂O₃ on PET in PA-ALD.

The combination of the mutually beneficial characteristics of the polymer and the ALD technique allows for the creation of a more critical role in the effort to develop high-performance lithium-ion batteries.

In this study, a greenhouse solar dryer with double-pass multi-hollow collector for leaf drying was design, constructed, and evaluated. From the result, the double pass solar air collector with multi-hollow tube is capable of increasing air temperature by 5.5℃-10.8℃ compared to ambient air temperature. Thermal efficiency of the dryer was evaluated for passive and active modes, where 47.2% and 50% are recorded respectively. The moisture reduction on mass basis in passive and active dryer recorded was 44% and 74%, respectively. The specific moisture extraction rate (SMER) and specific energy consumption (SEC) of passive dryer was determined to be 0.198 kg per kWh and 5.047 kWh per kg, and active dryer at 0.210 kg per kWh and 4.769 kWh per kg, respectively.

Atomic layer deposition (ALD) was used to coat a polyethylene terephthalate (PET) polymer substrate with TiO₂ film. The TiO₂ was grown onto the surface with better film coverage by using thicker ALD deposition. Further evaluation on the coated substrates indicated that the reactive sites of –C=O that existed on PET surface played a significant contribution to facilitating the initial ALD growth of the TiO₂ thin film. The chemical composition of the coated substrates was characterised using energy dispersive X-ray spectroscopy, which showed that increasing the TiO₂ film thickness increased the Ti element content. Two growth mechanisms, namely, diffusion growth and direct coordination through the precursor coordination with surface reactive sites of –C=O with product release occurred simultaneously in the initial growth of TiO₂ coating onto PET polymer by ALD. The surface alteration of the coated ALD was characterised by Fourier transform infrared spectroscopy, which showed that the hydroxyl –OH groups emerged in the TiO₂ ALD film.

In this study, two-dimensional nanosheets are fabricated by atomic layer deposition with sacrificial polymers. This method enables to fabricate free thin nanosheets with thickness of nanoscale. In the preparation, TiO₂ and ZrO₂ metal oxides are deposited onto substrates of Polyacrylic acid and Polyvinyl alcohol acted as sacrificial substrates. By dissolving the substrate, free-thin sheets layer with a high aspect ratio can be achieved due to the exfoliation mechanism. It was shown that the 2D nanosheets can be successfully formed on the deposited ALD material layer which can withstand the emergence of interfacial stress in the region of ALD layer – sacrificial substrate. The achieved nanosheets are characterized by using AFM, which shows that the thickness of both TiO₂ and ZrO₂ nanosheets are ∼ 80 nm which formed with 1000 and 600 ALD cycles, respectively. The 2D nanosheets obtained in this study have potential applications for photocatalysis, water splitting, and lithium ion battery.