Functionalized exfoliated graphene oxide (EGO) for supercapacitor electrodes have been synthesized by simple chemical methods from the exfoliated graphite (EG) as precursor. Structural and morphological characterizations of EGO have been carried out using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), FTIR and Raman spectroscopy. Electrochemical performance of these electrodes has been investigated using cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy. The fabricated supercapacitor gave a specific capacitance of 146 Fg^-1 and energy density of 20 Wh·kg^-1 for a highly oxidized sample with more functional groups compared to pure, lower level oxidized and reduced samples. The single and multi layered graphene oxide sheets produced by this method have a lower degree of agglomeration. We found that the graphene oxide with functional oxygen groups of quinine type enhances the capacitance compared to other oxygen functional groups

Proton exchange membrane fuel cell (PEMFC) performance degrades when impurities are present in the anode fuel gas, referred to as catalyst poisoning. This paper investigates the effect of carbon dioxide and ammonia as impurities in the anode gas of the PEMFC, and found that the presence of CO2 decreases the performance of the fuel cell by up to 10%. The performance loss depends on the CO2 concentration and the exposure time. The voltage loss is recoverable on passing pure hydrogen gas, indicating that a permanent poisoning of the catalyst layer has not taken place. Exposure of the fuel cell to ammonia beyond 20 ppm, even for a short duration, causes permanent PEMFC failure, probably due to the deterioration of the membrane.

Abstract. Activated carbons (ACs) are being used as energy storage material especially for hydrogen storage application. In the present work, AC materials were synthesized from jute fibers, activated and treated using KOH to increase the porosity of samples. These AC samples retained the fibrous structure even after chemical activation at high temperature of 700°C. Channel like structures were formed which helps to increase the hydrogen storage capacity. The surface area of these samples varied from 380 to 1220 m 2 /g due to carbonization and activation treatment. The sample with high surface area of 1224 m 2 /g showed a high hydrogen uptake capacity of 1.2 wt.% at 30°C and 40 bar of H 2 gas pressure. This sample also showed a high pore volume of 0.74 cm 3 /g. These results indicate that the raw material jute fibers can be used as hydrogen storage medium after thermal and chemical treatment which increases the surface area and micropore volume.

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The reactions of M+NSO~( M+ = K+ or (Me2N)3S+) with Ph2AsCl or RAsCl2 in acetonitrile produce Ph2AsNSO (1) or RAs(NSO)2 (R = t-Bu (2a), Ph (2b)). Treatment of Cr(CO)5(THF) with 1 or 2 gives Cr(CO)5(Ph2AsNSO) (3) or Cr-(CO)5[RAs(NSO)2] (R = r-Bu (4a), Ph (4b)), respectively. An X-ray structural determination of 3 shows that the ligand adopts a cis configuration and is bonded to chromium via the arsenic atom. Crystal data: monoclinic, space group Pl\jc, a = 12.389(4)A,b = 10.293 (3) Á, c = 16.031 (6) ,ß = 104.50 (1)°, V = 1979.1 Á1 23, Z = 4. The structure was solved by Patterson techniques and refined by full-matrix least-squares techniques to give a final R = 0.056 and Rw = 0.057. The bond distances in the ligand are 4(As-N) = 1.889 (6), 4(N-S) = 1.496 (7), and d(S-O) = 1.457 (9) Á, and the bond angles at nitrogen and sulfur are 127.5 (4) and 120.2 (4)°, respectively. The reaction of 2b with Pt(C2H4)(PPh3)2 results in As-N bond cleavage to give ck-Pt-(PPh3)2(NSO)2 in good yield. The thermolysis of 2b produces the eight-membered ring Ph2As2S2N4. Complexes of the type ck-Cr(CO)4(R2As2S2N4) (R = r-Bu (5a), Ph (5b)) are obtained from the reaction of R2As2S2N4 and ck-Cr(CO)4(C7H8).

In recent years, intramolecular aryl radical cyclisation has emerged as a useful route for the synthesis of benzannulated heterocycles and carbocycles. The aryl radicals are generated in situ from aryl halides (iodides or bromides) with tributylstannyl hydride-AIBN, SmI 2 , Co() or under photochemical conditions. The present work envisages the generation of aryl radicals by cathodic reduction of the carbon-iodine bond of N-(2-iodophenyl)-N-alkylcinnamides and their intramolecular cyclisation. The cathodic reduction of N-(2-iodophenyl)-N-alkylcinnamides under deaerated conditions in DMF gave 1-alkyl-3-benzylindolin-2-ones regioselectively and in the presence of oxygen yielded surprisingly 1-alkyl-3-hydroxy-3-benzylindolin-2-ones. Both these products were formed by a 5-exo-trig process in good yields. A mechanism for the formation of the products has been proposed through the use of cyclic voltammetry, coulometry and controlled-potential electrolysis as well as deuterium labelling.

<p class="PaperAbstract"><span lang="EN-US">The present work investigates the efficiency of an alkaline water electrolysis process in the presence of a complexing agent like citric acid (CA) when added directly into the electrolyte during the electrolytic process. High surface area nickel electrodes prepared by electrodeposition technique were used as the electrode to evaluate the efficiency of the oxygen evolution reaction (OER) by the polarization measurements and cyclic voltammetry. The quantity of the complexing agent CA in the electrolyte was varied from 0-1 wt. %. An increase in the current density of about 25% resulted at a temperature of 30 °C in the presence of 0.2 wt. % of CA at 1.0 V </span><span lang="EN-US">vs.</span><span lang="EN-US"> Hg/HgO. CA was found to improve performance by forming a complex with the alloy electrode and by formation of the high surface area catalyst for efficient OER.</span></p>