Nitrogenated diamond-like (DLC:N) carbon thin films have been deposited by microwave surface wave plasma chemical vapor deposition on silicon and quartz substrates, using argon gas, camphor dissolved in ethyl alcohol composition and nitrogen as plasma source. The deposited DLC:N films were characterized for their chemical, optical, structural and electrical properties through X-ray photoelectron spectroscopy, UV/VIS/NIR spectroscopy, Raman spectroscopy, atomic force microscope and current–voltage characteristics. Optical band gap decreased (2.7 to 2.4 eV) with increasing Ar gas flow rate. The photovoltaic measurements of DLC:N / p-Si structure show that the open-circuit voltage (Voc) of 168.8 mV and a short-circuit current density (Jsc) of 8.4 μA/cm2 under light illumination (AM 1.5 100 mW/cm2). The energy conversion efficiency and fill factor were found to be 3.4 × 10− 4% and 0.238 respectively. 相似文献
Plasma-assisted catalysis was used for the destruction of 500 ppm of dichloromethane, CH2Cl2 (DCM), in gas streams of air using a non-thermal, atmospheric pressure plasma utilising a dielectric packed bed. The combination of plasma and catalyst gave improved destruction of DCM. Eight catalysts which including alumina, TiO2 and various zeolites were investigated with the finding that alumina in a one-stage reactor configuration and TiO2 and HZSM-5 in two-stage configurations gave the best DCM destructions. The sodium zeolites are capable of reducing by 50% the unwanted NOx by-products, formed by plasma processing in air. The nature of the catalyst is important in terms of the destruction efficiency, end-product selectivity and NOx reduction. 相似文献
The role of ozone was studied for two different configurations combining non-thermal plasma (NTP) and heterogeneous catalysis, namely the use of a gas phase plasma with subsequent exposure of the effluent to a catalyst in a packed-bed reactor (post-plasma treatment) and the placement of the catalyst directly in the discharge zone (in-plasma catalysis). Non-porous and porous alumina and silica were deployed as model catalysts. The oxidation of immobilised hydrocarbons, toluene as a volatile organic compound and CO as an inorganic pollutant were studied in both operational modes.
While conversion and selectivity of hydrocarbon oxidation in the case of catalytic post-plasma treatment can be fully explained by the catalytic decomposition of O3 on γ-Al2O3, the conversion processes for in-plasma catalysis are more complex and significant oxidation was also measured for the other three materials (-Al2O3, quartz and silica gel). It became obvious that additional synergetic effects can be utilised in the case of in-plasma catalysis due to short-lived species formed in the NTP.
The capability of porous alumina for ozone decomposition was found to be correlated with its activity for oxidation of carbon-containing agents. It could be clearly shown that the reaction product CO2 poisons the catalytic sites at the γ-Al2O3 surface. The catalytic activity for O3 decomposition can be partially re-established by NTP treatment. However, for practical purposes the additional reaction pathways provided by in-plasma catalytic processes are essential for satisfactory conversion and selectivity. 相似文献
A fluidized bed granulation method, pressure swing granulation (PSG), was applied to granulation of a hardmetal powder without pressing lubricants for making the upstream process of spark plasma sintering (SPS) more efficient.
The properties of the granules were examined and compared with those of spray dried granules and extruded ones under the present system using a sieve.
Spherical granules between 0.15 and 0.84 mm in diameter difficult to obtain by the spray drying were obtained with high yield. The flowability of the granules was far better than that of spray dried granules and similar to that of extruded ones. Iron contamination and oxidization during pressure swing granulation were tolerable to the real production. 相似文献
