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In this study, the silicon-based interlayers for hydrogenated amorphous carbon (a-C:H) coating on a chromium-plated substrate are presented. The a-Si, a-Si:N, a-Si:H and a-Si _x C _y :H interlayers with a thickness of about 306 nm were deposited by direct current magnetron sputtering technique. The a-C:H films with a thickness of about 317 nm was prepared as a top layer by radio frequency-plasma chemical vapor deposition. The a-C:H films with silicon-based interlayers were characterized by x-ray photoelectron spectroscopy, Raman spectroscopy, field emission-secondary electron microscopy, nanoindentation, micro-scratching, and electrochemical corrosion measurements in terms of their structure, morphology, mechanical and adhesive properties, and corrosion resistance. The a-C:H films with an a-Si:H interlayer exhibit the lowest corrosion current density, which is about 36 times lower than that of the uncoated chromium-plated substrate. In addition, the hardness increases from 8.48 GPa for the uncoated substrate to 20.98 GPa for the a-C:H/a-Si:H sample. The mixing with hydrogen gas could reduce the residual oxygen during the deposition process, which could reduce the Si–O bonding and improve the adhesion strength between the a-C:H film and the a-Si:H interlayer and the a-Si:H interlayer and the substrate. Therefore, it can be concluded that the protective a-C:H coating with an a-Si:H interlayer has excellent potential to significantly improve the durability and extend the service life of materials used in abrasive and corrosive environments.

This work presents a novel route for utilizing waste from power plants to create a new power source (solar cells). Bottom ash (BA) ceramic micro-particles were studied to improve an electrocatalytic activity in solar cell applications for the first time. In the counter electrodes (CE) of dye-sensitized solar cells (DSSC), bottom ash was mixed with PEDOT:PSS (PP) and polyvinylpyrrolidone (PVP) (BA/PP/PVP) in volume ratios of 3:7, 4:6, 5:5, and 6:4. We found that bottom ash has a significant impact in improving the electrocatalytic activity and DSSC efficiency of these cells. Moreover, the PP and PVP ratios have a high impact on solar cell performance. The BA/PP/PVP-(6:4) counter electrode attained a higher DSSC efficiency, 2.70%, compared to the other electrodes prepared under similar conditions and a Pt CE based DSSC (3.23%) at AM 1.5 (100 mWcm−2 ). The influences of bottom ash and PP/PVP ratios on film structure, electrocatalytic activity in − I3 reduction, redox reaction rate, and electron transport were characterized using SEM, CV, Tafel, and EIS, respectively. The results show that low-cost BA/PP/PVP-(6:4) CE is a promising new alternative to Pt CEs in DSSCs. [ABSTRACT FROM AUTHOR]

A low-pressure capacitively coupled discharge was used to study antimicrobial treatment in herbal tea. Ambient air with a relative humidity of 40% was used as a precursor gas and fed into the chamber via a perforated power electrode. An electrical discharge plasma was produced at a radio frequency of 10 kHz and power of 80 W. The operating pressure during treatment was kept constant at 260 Pa. The target microorganisms, Escherichia coli and Staphylococcus aureus, isolated from the herbal tea were inoculated on nutrient agar petri dishes and exposed to the plasma for 0.5, 1.0, 1.5, and 2.0 min. All treatments were carried out in triplicate for different exposure times to calculate the D-value by the enumeration method. D-values of 0.73 and 0.67 min were obtained corresponding to E. coli and S. aureus reduction, respectively.