Plasma diagnostics were performed during excimer laser ablation of graphite in a low-pressure atmosphere using time- and space-resolved optical emission spectroscopy. The laser fluence and nitrogen pressure were set to values typically applied to pulsed laser deposition of thin films. Under these conditions, optical emission spectra were dominated by continuum emission and spectral lines from carbon ions during the early plasma phase , when the carbon vapour is located in the vicinity of the target surface, whereas molecular bands of molecules and CN radicals were essentially observed at later times when the vapour expands through the ambient gas. Emission spectra of , CN and were recorded as functions of time for various distances from the target. From computer simulations of molecular spectra, we deduced rotational and vibrational temperatures. The acquired information about the kinetics of excited plasma species and gas phase reactions contributes to a better understanding of pulsed laser deposition of carbon nitride thin films.

Plasma polymerized allylamine (ppAA) films were deposited in a radio‐frequency glow discharge plasma reactor using a continuous‐wave mode and varying the discharge power from 15 to 125 W. The deposition rate reached 26 nm · min−1 and was constant within at least half an hour of process. The chemical structure and elemental composition of the deposited films were investigated by Fourier transform infrared and X‐ray photoelectron spectroscopies, whereas surface properties were analyzed by atomic force microscopy and surface free energy measurement. A special focus is given to the stability of ppAA in aqueous media and primary amine quantification. The use of fluorescent microscopy and UV‐Visible spectroscopy enabled us to detect and quantify the primary amine, respectively. All the studied parameters varied widely with enhanced power with a transition point around 50 W. Over this value, the results remain relatively unchanged.

A far cold remote nitrogen (FCRN) plasma, eventually doped with oxygen, was used to modify the surface properties of a polyethylene (PE) powder. The process associates both remote plasma and fluidized bed technologies. Two applications are described. The first one, for increasing the hydrophilic character of PE, only requires a single plasma treatment. The second application involves FCRN plasma polymerization of 1,1,3,3-tetramethyldisiloxane mixed with oxygen to obtain a hydrophobic film on the powder surface. The wettability evolution of the PE powder was followed by contact angle measurements (Washburn method) versus different experimental parameters. The surface modifications induced by the treatments were studied by XPS.

Cover: AFM scans (5µm × 5µm) of 500 nm thick films as deposited on Si from processes a) RFICP (full vertical scale: 12.6 nm), b) MIRA (full vertical scale: 44.9 nm), and c) DECRP (full vertical scale: 27.7 nm). Further details can be found in the Full Paper by P. Supiot,* C. Vivien, A. Granier, A. Bousquet, A. Mackova, D. Escaich, R. Clergereaux, P. Raynaud, Z. Stryhal, and J. Pavlik on page 100.

Summary: Five hundred nanometer thick organosilicon coatings are prepared on Si substrates in parallel by the plasma‐assisted polymerisation of hexamethyldisiloxane (HMDSO) in an RF‐inductively coupled plasma (RFICP) and distributed electron cyclotron resonance plasma (DECRP) at low pressure (0.27 Pa) and of tetramethyldisiloxane (TMDSO) premixed with oxygen in an N2 microwave induced remote afterglow (MIRA) at 560 Pa. The structure of these different films is analyzed by different techniques, such as Fourier‐transform infrared spectroscopy, Rutherford backscattering spectrometry, atomic force microscopy, ellipsometry, and contact angle measurements. Results of the film composition (at least 30% carbon content), optical properties, and morphology indicate a low cross‐linking degree accompanied by short chain length for RFICP and DECRP films, in contrast to a high‐molecular‐weight structure observed for the MIRA film. Carbon removal is achieved within the same plasma reactors by further oxygen‐containing plasma treatment performed in the RF‐ICP (3.33 Pa), DECRP (0.27 Pa, −200 V biased substrate), and MIRA (N2/O2 (98.7:1.3, 560 Pa)) reactors. The same measurements are carried out on the treated samples in order to detect the main changes in film composition, optical properties, and morphology. The evolution of surface energy is also studied. The results are discussed according to film structure and process specificity.O/Si and C/Si elemental ratios calculated from RBS analysis for an as‐deposited RF‐inductively coupled plasma coating (RFICP) and films post‐treated by N2/O2 microwave induced remote afterglow (MIRA), O2 RFICP and O2 distributed electron cyclotron resonance plasma (DECRP, biased sample) processes.imageO/Si and C/Si elemental ratios calculated from RBS analysis for an as‐deposited RF‐inductively coupled plasma coating (RFICP) and films post‐treated by N2/O2 microwave induced remote afterglow (MIRA), O2 RFICP and O2 distributed electron cyclotron resonance plasma (DECRP, biased sample) processes.

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Lignin is the second most abundant polymer after cellulose in lignocellulosic biomass. Its aromatic composition and recalcitrant nature make its valorization a major challenge for obtaining low molecular weight aromatics compounds with high value-added from the enzymatic depolymerization of industrial lignins. The oxidation reaction of lignin polymer using laccases alone remains inefficient. Therefore, researches are focused on the use of a laccase-mediator system (LMS) to facilitate enzymatic depolymerization. Until today, the LMS system was studied using water-soluble lignin only (commercial lignins, modified lignins, or lignin model compounds). This work reports a study of three LMS systems to depolymerize the three major industrial lignins (organosolv lignin, Kraft lignin, and sodium lignosulfonate). We show that an enzymatic depolymerization of these lignins can be achieved by LMS using laccase from Trametes versicolor, 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt as mediator and a cosolvent (25% of 1,4-dioxane) to enhance the solubilization of lignins. C 2020

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