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Gamma radiation can cause structural defects in metal oxide thin films, affecting their conversion efficiency. This study focuses on synthesizing and characterizing Tungsten oxide (WO3) films for photo-electrochemical (PEC) water-splitting applications. The pristine WO3 film was irradiated with a Co-60 gamma source to improve its photocatalytic activity and was named G-WO3. The resulting G-WO3 thin films showed a decrease in the optical direct band gap and showed higher photocurrent density and lower charge transfer resistance for PEC applications. The carrier charge density (Nd) values were found to be increased after γ-radiation. The synthesized G-WO3 thin films possess good stability and reusability for photo-electrochemical water-splitting applications. [ABSTRACT FROM AUTHOR]

In this study, influence of Al substitution on hydrogen storage properties of Ti2CrV alloy has been investigated in detail. The alloys Ti2–xCrVAlx (x = 0.05, 0.1) were synthesized by arc melting method, and composition, type of crystal structure and hydrogen storage properties were evaluated. X-ray diffraction studies confirmed that all the alloys form single-phase bcc structures. Ti1.95CrVAl0.05 alloy is found to absorb a maximum of 3.9 wt% of hydrogen at room temperature and moderate hydrogen pressure. The plateau pressure of the studied alloys increases with an increase in Al concentration. The results confirm that among the studied alloys, Ti1.95CrVAl0.05 alloy shows the fastest hydrogen absorption kinetics and improved cyclic stability with a marginal decrease in total hydrogen absorption capacity compared to the parent alloy. [ABSTRACT FROM AUTHOR]

Activated porous carbons have been prepared from commercially available table sugar (sucrose) based on KOH activation. XRD and Raman spectroscopic studies confirmed that increasing KOH to C ratio causes significant disorder in sp2 carbon network. TEM, SAXS and N2 adsorption–desorption studies revealed that the samples consist of micro and meso pores. Presence of oxygen containing functional groups on the surface of these activated carbon samples has been confirmed from EDS, FTIR and XPS studies. The maximum hydrogen storage capacity is as high as 2.3 wt% at 123 K and 45 bar pressure for the sample prepared with KOH:C ratio of four. This has been explained based on its higher micropore surface area and greater micropore volume corresponding to this sample. Adsorption enthalpy for this sample is ~ 10 kJ/mol which is quite high compared to that of a commercially available high surface area activated carbon (AX21) and this high adsorption enthalpy is attributed to the presence of oxygen related functional groups on its surface. [ABSTRACT FROM AUTHOR]

This paper deals with hydrogen storage properties of Ti-V based BCC solid solution incorporated with Fe. The alloy with composition Ti2FeV was prepared by arc melting method. X-ray diffraction (XRD) and energy dispersive X-ray analysis studies confirmed formation of solid solution phase with uniform composition and BCC structure. SEM studies revealed the formation of irregular shaped particles with size in the range of few microns up on hydrogenation of the parent alloy. The alloy shows maximum hydrogen storage capacity of 3.41 wt.% at 20 bar and 303 K and the thermodynamic parameters established near room temperature suitability of the alloy for solid state hydrogen storage applications. Hydrogenation kinetics is found to be quite fast and detailed kinetic analysis were done to underscore the hydrogenation mechanism. Activation energy during the initial stage of hydrogenation is found to be 30.8 kJ/mol. The value decreases to 14.4 kJ/mol for extended duration of hydrogenation, and this is explained based on difference in rate determining steps existing at different time scales. Extent of hydrogen absorption as a function of temperature and time for Ti2FeV alloy. [ABSTRACT FROM AUTHOR]