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The effects of SrTiO3on the hydrogen storage properties of MgH2have been studied for the first time. The onset dehydrogenation temperature of the MgH2-10 wt% SrTiO3is found to be 275 °C, which is 55 °C lower as compared to the as-milled MgH2. The composite is able to absorb 4.3 wt% of hydrogen in 60 min instead of 1.1 wt% for the as-milled MgH2. Meanwhile, the composite is able to release 5.3 wt% of hydrogen in 17 min compared to 1.9 wt% by the as-milled MgH2at 320 °C. The calculated Eaof the MgH2-10 wt% SrTiO3is 109 kJ/mol, which is 26.3 kJ/mol lower than the calculated Eaof the as-milled MgH2. The SrTiO3is not decomposed during the ball milling and the re/dehydrogenation processes. The catalytic effect shown by the SrTiO3is owing to its ability to change the physical structure of the MgH2particles during the ball milling process.

This study emphasizes the catalytic function of TiF3on hydrogen storage properties and the reaction mechanism of the MgH2-Na3AlH6-LiBH4produced by employing the ball-milling technique, which has a molar ratio of 1:1:4. It discovered that the mixture of Na3AlH6and LiBH4reacted through a metathesis reaction and transformed into Li3AlH6and NaBH4composite upon the ball milling procedure. MgH2-Li3AlH6-NaBH4destabilized system with TiF3catalyst has displayed four decomposition tiers throughout the heating procedure. The initial tier of hydrogen release in the composite occurs at temperatures of 100 °C and 75 °C lower than in the catalyst-free composite. Continuous heating resulted in two through four dehydrogenation tiers, with an overall capacity of 10.1 wt% hydrogens released (at temperatures of 200 °C, 350 °C, and 400 °C, respectively). In contrast to the Mg-Na-Al-Li-B-H catalyst-free composite, incorporating the TiF3catalyst demonstrates a faster hydrogen uptake and release rate. The apparent activation energy (Ea) for the dissociation of Li3AlH6, MgH2, and NaBH4in the composite with TiF3catalyst was remarkably abridged compared to the catalyst-free ternary system (Kissinger plot; 23, 20, and 13 kJ/mol, respectively for doped composite). TiF3's considerable catalytic performance is ascribed to the in-situ production of AlTi and AlF phases during the dehydrogenation process of TiF3and Li3AlH6. Once generated, the AlTi and AlF phase serves as a genuine catalyst in the MgH2-Na3AlH6-4LiBH4-TiF3ternary system.

In this work, mesoporous activated carbon with high surface area was synthesized from swamp taro stalk by single step ZnCl2 activation. The synthesized activated carbon was characterized by Na2S2O3 volumetric method, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM) and N2 adsorption-desorption analyses. Under the single step ZnCl2 activation, the registered iodine number, BET surface area, total pore volume and pore diameter were 1087.57 mgg-1, 1242.26 m2g-1, 0.73cm3g-1 and 3.72 nm respectively with yield of 25.34%. SEM analysis evidenced the well-formation of porous structure. Type IV isotherm with H2 loops obtained from N2-sorption studies indicates the ink bottles shape mesoporous network structure. This research proved the successful conversion of plant waste into high grade activated carbon.

In this study, highly porous activated carbon was prepared from Cyrtosperma chamissonis petioles via single step H3PO4 activation. The effect of impregnation temperature (RT – 90 °C) on the yield, porosity and surface area was investigated. The synthesized activated carbons were characterized by Na2S2O3 volumetric method, SEM/EDX and N2 adsorption-desorption analyses. The optimization investigation clearly showed that the impregnation temperature affected on the yield and the specific surface area of the materials. Under the optimum impregnation temperature of 75 °C, the registered iodine number and BET surface area were 1129.23 mgg-1 and 1390.41 m2g-1 respectively with yield percentage of 35.82. This preliminary study proves the successful conversion of plant waste into value added porous materials.