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Yttrium oxide thin film deposition by atomic layer epitaxy (ALE) was studied at 200±425 C using Y(thd) 3 , Y(thd) 3 (bipyridyl), or Y(thd) 3 (1,10-phenanthroline) (thd = 2,2,6,6-tetramethyl-3,5-heptanedione) as an yttrium precursor, and ozone as an oxygen source. All yttrium precursors were analyzed by thermogravimetry/differential thermal analysis (TG-DTA) and mass spectrometry (MS). Soda lime glass and Si(100) were used as substrates. With all precursors, a constant deposition rate of 0.22±0.23 (cycle) ±1 was observed at 250±350 C on both substrates, indicating a surface-controlled growth and similar surface species at the deposition temperatures used. The effect of growth parameters, such as reactant pulsing times, was investigated in detail at 350 C using Y(thd) 3 . Deposited films were characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM) in order to determine crystallinity and surface morphology, while ion-beam analysis and X-ray photoelectron spectroscopy (XPS) were used to analyze stoichiometry and impurity levels. Infrared (IR) measurements were performed to determine the type of carbon impurity. Crystalline films with a (400) dominant orientation were obtained when depositions were carried out within the ALE window (temperature range of 250±375 C), but films deposited below 250 C were nearly amorphous. Preferential orientation changed from (400) to (222) when deposition temperatures were raised slightly above the ALE window to 375 C, where a partial decomposition of Y(thd) 3 probably takes place. Judging from the impurity levels of the films and growth rates, the adducting of Y(thd) 3 does not bring about any advantages in the ALE growth of Y 2 O 3 .

Multiscale carbon supraparticles (SPs) are synthesized by soft-templating lignin nano- and microbeads bound with cellulose nanofibrils (CNFs). The interparticle connectivity and nanoscale network in the SPs are studied after oxidative thermostabilization of the lignin/CNF constructs. The carbon SPs are formed by controlled sintering during carbonization and develop high mechanical strength (58 N·mm–3) and surface area (1152 m2·g–1). Given their features, the carbon SPs offer hierarchical access to adsorption sites that are well suited for CO2 capture (77 mg CO2·g–1), while presenting a relatively low pressure drop (∼33 kPa·m–1 calculated for a packed fixed-bed column). The introduced lignin-derived SPs address the limitations associated with mass transport (diffusion of adsorbates within channels) and kinetics of systems that are otherwise based on nanoparticles. Moreover, the carbon SPs do not require doping with heteroatoms (as tested for N) for effective CO2 uptake (at 1 bar CO2 and 40 °C) and are suitable for regeneration, following multiple adsorption/desorption cycles. Overall, we demonstrate porous SP carbon systems of low cost (precursor, fabrication, and processing) and superior activity (gas sorption and capture).

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This paper demonstrates a high-throughput approach to fabricate nanocellulose films with multifunctional performance using conventionally existing unit operations. The approach comprises cast-coating and direct interfacial atmospheric plasma-assisted gas-phase modification along with the microscale patterning technique (nanoimprint lithography, NIL), all applied in roll-to-roll mode, to introduce organic functionalities in conjunction with structural manipulation. Our strategy results in multifunctional cellulose nanofibrils (CNF) films in which the high optical transmittance (∼90%) is retained while the haze can be adjusted (2–35%). Concomitantly, the hydrophobic/hydrophilic balance can be tuned (50–21 mJ/m 2 with the water contact angle ranging from ∼20 up to ∼120°), while intrinsic hygroscopicity of CNF films is not significantly compromised. Therefore, a challenge to produce multifunctional bio-based materials with properties defined by various high-performance applications conjoined to the lack of efficient processing strategies is elucidated. Overall, economically and ecologically viable strategy, which was realized by facile and upscalable unit operations using the R2R technology, is introduced to expand the properties’ spaces and thus offer a vast variety of interesting applications for CNF films.

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