Hydrogen energy, economy and storage: Review and recommendation

A review on the current progress of metal hydrides material for solid-state hydrogen storage applications

Review of hydrogen storage techniques for on board vehicle applications

Materials, technological status, and fundamentals of PEM fuel cells – A review

Hydrogen is a promising alternative energy carrier that can potentially facilitate the transition from fossil fuels to sources of clean energy because of its prominent advantages such as high energy density (142 MJ kg(-1); ref. 1), great variety of potential sources (for example water, biomass, organic matter), light weight, and low environmental impact (water is the sole combustion product). However, there remains a challenge to produce a material capable of simultaneously optimizing two conflicting criteria--absorbing hydrogen strongly enough to form a stable thermodynamic state, but weakly enough to release it on-demand with a small temperature rise. Many materials under development, including metal-organic frameworks, nanoporous polymers, and other carbon-based materials, physisorb only a small amount of hydrogen (typically 1-2 wt%) at room temperature. Metal hydrides were traditionally thought to be unsuitable materials because of their high bond formation enthalpies (for example MgH(2) has a ΔHf~75 kJ mol(-1)), thus requiring unacceptably high release temperatures resulting in low energy efficiency. However, recent theoretical calculations and metal-catalysed thin-film studies have shown that microstructuring of these materials can enhance the kinetics by decreasing diffusion path lengths for hydrogen and decreasing the required thickness of the poorly permeable hydride layer that forms during absorption. Here, we report the synthesis of an air-stable composite material that consists of metallic Mg nanocrystals (NCs) in a gas-barrier polymer matrix that enables both the storage of a high density of hydrogen (up to 6 wt% of Mg, 4 wt% for the composite) and rapid kinetics (loading in <30 min at 200 °C). Moreover, nanostructuring of the Mg provides rapid storage kinetics without using expensive heavy-metal catalysts.

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Air-stable magnesium nanocomposites provide rapid and high-capacity hydrogen storage without using heavy-metal catalysts

Nanotechnology becomes the most innovative and interesting field for researchers in last decade. Nanotechnology deals with particles of size 1-100 nm. Recent advances in science and nanotechnology leads to the wide applications of metal and metal oxide nanoparticles in several fields. Copper oxide (CuO) nanoparticles have a large potential due to its distinct properties and environment friendly behaviour. There are several methods to synthesize CuO nanoparticles but due to environment benign process, availability of plants, non-toxicity and cheap process we prefer green approach. In this paper we synthesize CuO nanoparticles via green route in which Aloevera leaf (Aloe Barbadensis) extract used as reducing and capping agent. The formation of CuO can be found with naked eyes. The phytochemicals present in leaf extract plays an important role in synthesis. In synthesis process copper sulphate penta hydrate (Cu(So4)2.5H2O) use as metal precursor salt and NaOH used to maintain the pH of the solution. The synthesis process has been carried out at temperature 50 0C. The synthesized nanoparticles thereby obtained characterized by various analytical techniques like FESEM with EDX, XRD, FTIR and UV-Visible. The surface morphology of spherical shape revealed by Field Emission Scanning Electron Microscope (FESEM), elemental analysis by Energy Dispersive analysis (EDX), Fourier Transform Infrared (FTIR) revealed the different groups attached with CuO nps, the structure and average particle size of 5-6 nm estimated by XRD and the Optical properties revealed by UV-Vis spectroscopy.

Chhagan Lal

Papers

Synthesis and characterization of cuo nanoparticles by aloe barbadensis leaves