Niobium Pentoxide thin films employ simple colloidal suspension at low preparation temperature

In this work a nano-colloidal suspension is used to prepare Nb2O5 thin films. The effect of different substrates on structural properties of niobium pentoxide thin film deposited by spin coating technique on silicon and quartz substrates are presented. We observed that the obtained structure is monocline in both substrates. The diffraction peaks in both substrates ensured the successful formation of Nb2O5 thin films with a clear polymorphous structure. However, the structure became more crystalline with additional distinguished peaks on silicon substrate comparing to quartz substrate. The extracted structural parameters from X-Ray diffraction show that the grain size of the thin films on quartz is smaller than silicon with the values of 16.47 nm and 20.98 nm respectively. The stress measurement records the values of 0.19 and 0.00719 for the thin films deposited on silicon and quartz substrates respectively. Effects of film thickness depicted increment in the absorbance and reduction in the band gap. Energy gaps of 2.7, 2.58 and, 2.5 eV are measured as a result of increasing the film thicknesses of 325, 420 and 450 nm respectively

Niobium Pentoxide thin films employ simple colloidal suspension at low preparation temperature

In this work a nano-colloidal suspension is used to prepare Nb2O5 thin films. The effect of different substrates on structural properties of niobium pentoxide thin film deposited by spin coating technique on silicon and quartz substrates are presented. We observed that the obtained structure is monocline in both substrates. The diffraction peaks in both substrates ensured the successful formation of Nb2O5 thin films with a clear polymorphous structure. However, the structure became more crystalline with additional distinguished peaks on silicon substrate comparing to quartz substrate. The extracted structural parameters from X-Ray diffraction show that the grain size of the thin films on quartz is smaller than silicon with the values of 16.47 nm and 20.98 nm respectively. The stress measurement records the values of 0.19 and 0.00719 for the thin films deposited on silicon and quartz substrates respectively. Effects of film thickness depicted increment in the absorbance and reduction in the band gap. Energy gaps of 2.7, 2.58 and, 2.5 eV are measured as a result of increasing the film thicknesses of 325, 420 and 450 nm respectively

Thermodynamic analysis of hydrogen production from methanol-ethanol-glycerol mixture through dry reforming

Thermodynamic properties of methanol-ethanol-glycerol dry reforming have been studied with the method of Gibbs free energy minimisation for hydrogen production from methanol-ethanol-glycerol mixture. Equilibrium compositions were determined as a function of CO2/methanol-ethanol-glycerol molar ratios (CMEG) (1 : 6 - 6 : 1) where methanol-ethanol-glycerol is 1 : 1 : 1; reforming temperatures (573 - 1,273 K) at atmospheric pressure (unless stated otherwise). Optimum conditions for hydrogen production are CMEG 1 : 6, temperature 1,273 K, 1 bar pressure. This point is also optimum for the production of synthesis gas. Comparison of the moles of hydrogen produced from methanol-ethanol-glycerol mixture versus ethanol-glycerol mixture was made and exhibit paradoxical effects. Higher pressure and higher CMEG ratio does not encourage hydrogen formation. Under identified optimum conditions, carbon formation can be thermodynamically inhibited. The carbon yield can be reduced through reforming at higher temperatures