The recent interest and excitement in graphene has also opened up a pandora's box of other tw... more The recent interest and excitement in graphene has also opened up a pandora's box of other two-dimensional (2D) materials and material combinations which are now beginning to come to the fore. One family of these emerging 2D materials is transition metal dichalcogenides (TMDs). So far there is very limited understanding on the wetting behavior of 'monolayer' TMD materials. In this study, we synthesized large-area, continuous monolayer Tungsten Disulfide (WS2) and Molybdenum Disulfide (MoS2) films on SiO2/Si substrates by the thermal reduction and sulphurization of WO3 and MO3 thin films. The monolayer TMD films displayed an advancing water contact angle of ~83 deg as compared to ~90 deg for the bulk material. We also prepared bi-layer and tri-layer WS2 films and studied the transition of the water contact angle with increasing number of layers. The advancing water contact angle increased to ~85…
ABSTRACT The catalytic properties of the nanocomposites were evaluated at various temperatures du... more ABSTRACT The catalytic properties of the nanocomposites were evaluated at various temperatures during the gas-phase dehydration of glycerol, an environmental friendly reaction. A pressure of 1 atm and a glycerol/water molar ratio of 0.25 were applied. Nanocomposites possessing high surface area were synthesised, and silica-containing CeO2-MnO2, NiO-Al2O3 and CeO2-Al2O3 nanoparticles were obtained. The materials were characterised by XRD, Raman spectroscopy, TPR, TEM and SEM-EDX analysis, and the textural properties of the materials were determined. The effect of the structure, surface properties and textural parameters was evident in the unique properties of the nanoparticles, and the accessibility of the active sites dictated the catalytic activity. The basicity and reducibility of the nanoparticles on silica plays a critical role in the catalytic properties of the oxides.
Page 1. GENERAL AND APPLIED PHYSICS Combination of Raman, Infrared, and X-Ray Energy-Dispersion S... more Page 1. GENERAL AND APPLIED PHYSICS Combination of Raman, Infrared, and X-Ray Energy-Dispersion Spectroscopies and X-Ray Diffraction to Study a Fossilization Process Francisco Eduardo de Sousa Filho & João ...
The recent interest and excitement in graphene has also opened up a pandora's box of other tw... more The recent interest and excitement in graphene has also opened up a pandora's box of other two-dimensional (2D) materials and material combinations which are now beginning to come to the fore. One family of these emerging 2D materials is transition metal dichalcogenides (TMDs). So far there is very limited understanding on the wetting behavior of 'monolayer' TMD materials. In this study, we synthesized large-area, continuous monolayer Tungsten Disulfide (WS2) and Molybdenum Disulfide (MoS2) films on SiO2/Si substrates by the thermal reduction and sulphurization of WO3 and MO3 thin films. The monolayer TMD films displayed an advancing water contact angle of ~83 deg as compared to ~90 deg for the bulk material. We also prepared bi-layer and tri-layer WS2 films and studied the transition of the water contact angle with increasing number of layers. The advancing water contact angle increased to ~85…
ABSTRACT The catalytic properties of the nanocomposites were evaluated at various temperatures du... more ABSTRACT The catalytic properties of the nanocomposites were evaluated at various temperatures during the gas-phase dehydration of glycerol, an environmental friendly reaction. A pressure of 1 atm and a glycerol/water molar ratio of 0.25 were applied. Nanocomposites possessing high surface area were synthesised, and silica-containing CeO2-MnO2, NiO-Al2O3 and CeO2-Al2O3 nanoparticles were obtained. The materials were characterised by XRD, Raman spectroscopy, TPR, TEM and SEM-EDX analysis, and the textural properties of the materials were determined. The effect of the structure, surface properties and textural parameters was evident in the unique properties of the nanoparticles, and the accessibility of the active sites dictated the catalytic activity. The basicity and reducibility of the nanoparticles on silica plays a critical role in the catalytic properties of the oxides.
Page 1. GENERAL AND APPLIED PHYSICS Combination of Raman, Infrared, and X-Ray Energy-Dispersion S... more Page 1. GENERAL AND APPLIED PHYSICS Combination of Raman, Infrared, and X-Ray Energy-Dispersion Spectroscopies and X-Ray Diffraction to Study a Fossilization Process Francisco Eduardo de Sousa Filho & João ...
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