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Production of hydrogen by steam-reforming of ethanol has been performed using different catalytic systems. The present review focuses on various catalyst systems used for this purpose. The activity of catalysts depends on several factors such as the nature of the active metal catalyst and the catalyst support, the precursor used, the method adopted for catalyst preparation, and the presence of promoters as well as reaction conditions like the water-to-ethanol molar ratio, temperature, and space velocity. Among the active metals used to date for hydrogen production from ethanol, promoted-Ni is found to be a suitable choice in terms of the activity of the resulting catalyst. Cu is the most commonly used promoter with nickel-based catalysts to overcome the inactivity of nickel in the water-gas shift reaction. γ-Al2O3 support has been preferred by many researchers because of its ability to withstand reaction conditions. However, γ-Al2O3, being acidic, possesses the disadvantage of favouring ethanol dehydration to ethylene which is considered to be a source of carbon deposit found on the catalyst. To overcome this difficulty and to obtain the long-term catalyst stability, basic oxide supports such as CeO2, MgO, La2O3, etc. are mixed with alumina which neutralises the acidic sites. Most of the catalysts which can provide higher ethanol conversion and hydrogen selectivity were prepared by a combination of impregnation method and sol-gel method. High temperature and high water-to-ethanol molar ratio are two important factors in increasing the ethanol conversion and hydrogen selectivity, whereas an increase in pressure can adversely affect hydrogen production.

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Transesterification of Jatropha oil with methanol is carried over heterogeneous sodium aluminate catalyst to produce biodiesel.

A simple and green method for the large scale production of graphene by ball-milling of graphite with sucrose is exploited here.

Synthesis of various zirconium doped titania based photocatalysts were carried out by adapting different synthetic strategies. Doping is done on commercially available anatase titania, sol-gel titania and template mediated sol gel titania. A comparative study of the various prepared photocataysts was done using physico-chemical characterization techniques such as X-ray diffraction (XRD), surface area-pore volume measurements, UV-VIS Diffuse reflectance spectra (DRS), elemental analysis (XRF) and transmission electron microscopic (TEM) studies. The effect of zirconium and preparation methods on the photocatalytic degradation of methylorange is studied extensively. Both the surface properties and photo activity of zirconium doped titania were found to have a great dependence on the preparation methods. Among the different photocatalytic systems, the catalyst prepared by doping in the presence of urea template was found to produce a maximum photodegradation of 97.5%.

Good quality graphene is prepared in a scalable manner from fluorographite by nucleophilic substitution of F with OH− ions.

A low-temperature, Mn(II)-assisted sol-solvothermal strategy has been developed for the synthesis of positively surface-charged defective brown TiO 2−x flower aggregates with porous nature. The porous structure possessed enormous surface defect states such as trivalent titanium ion (Ti 3+ ) and oxygen vacancy (V o ) sites. The defect states present in the brown TiO 2−x facilitated enhanced absorption even in the NIR region of the solar spectrum, whereas for the negatively surface-charged TiO 2 sample, synthesized in the absence of Mn(II), the absorption was limited to the visible region. Obviously, band-gap narrowing occurred for brown TiO 2−x as compared to the yellow TiO 2 synthesized in the absence of Mn(II). Interestingly, studying the photocatalytic efficiency of these materials using a methyl orange−methylene blue (MO-MB) dye mixture model system under solar illumination revealed selective photocatalytic reversibility, with MB and MO photodegradation performed by yellow TiO 2 and brown TiO 2−x , respectively. This is the first report on the use of surface-charged brown TiO 2−x with porous flower aggregate morphology for selective photocatalysis.