Investigation of hydrogen storage in MWCNT–TiO2 composite

• Facile ultrasonication method is used to prepare MWCNTs–TiO2 composite.
• A maximum hydrogen storage capacity of 0.9 wt% is obtained at 100 °C.
• The system exhibits 100% desorption in the temperature range of 275–425 °C.
• Nature of binding of hydrogen is found to be weak chemisorption.

The hydrogen storage capacity of MWCNT–TiO2 composite has been evaluated in the present work. The composite has been prepared by means of ultrasonication followed by drop casting on substrates. Morphology, structural and functional group studies of the prepared samples are carried out by transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. Then, the samples are hydrogenated in the hydrogenation chamber as a function of time. Hydrogen storage capacity of the composite sample is found to be 0.9 wt% at 100 °C. Hydrogen uptake of the composite is accounted for the spillover mechanism in CNTs–metal oxide composite. Desorption temperature range, activation energy of desorption, binding energy of hydrogen are determined from thermogravimetric (TG) analysis.

The composite MWCNTs–TiO2 shows a maximum hydrogen storage capacity of 0.9 wt% at 100 °C and the entire (100%) stored hydrogen is released in the temperature range of 275–425 ºC.Figure optionsDownload as PowerPoint slide