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Solution combustion synthesis was used to prepare cobalt oxide nanoparticles at different fuel ratio (φ = 0.5, 1, and 1.75). The synthesized particles were characterized using XRD, SEM, TEM, FTIR and XPS to study the morphological and structural features. The fuel rich condition provides a reducing atmosphere limiting further oxidation of synthesized nanoparticles but produces more carbon residue on the catalyst surface compared to fuel lean conditions. Increasing the fuel ratio (φ value) from 0.5 to 1.75 increases the crystallite size and lowers the surface area. The electrocatalytic performance studies conducted by cyclic voltammetry (CV) and linear sweep voltammetry (LSV) indicate significant changes in catalytic activities due to variation in synthesis conditions. The LSV results obtained between potential of −1.2 V and 0.75 V shows all the three cobalt oxide catalysts to have bifunctional properties of being active for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), with Co synthesized at lower fuel ratio (φ = 0.5) displaying the highest current density. The onset potential for Co (φ = 0.5) is more positive than Co (φ = 1) and Co (φ = 1.75). The kinetic current density for Co (φ = 0.5) is 6.45 mA cm−2 and decreases with increase in fuel ratio. The OER current starts at ∼0.45 V for all the catalysts showing maximum density for Co (φ = 0.5) and gradually decreasing for catalysts synthesized at higher fuel ratio. Qatar Foundation;Qatar National Research Fund;Qatar University Scopus

In this study, a thermodynamic equilibrium analysis has been performed on ethanol dry reforming in presence of commonly used reducing agents such as glycine, hydrazine, urea and ammonia. The effect of these agents on hydrogen enrichment and carbon suppression has been investigated at one atmospheric pressure and 300 K 1200 K temperature. Among the investigated additives, hydrazine was found to be the most suitable for maximizing hydrogen production and removing elemental carbon formation. This study was further extended to ethanol steam reforming and similar conclusions were obtained. Industrial significance of this study is associated with reforming reactions where catalyst deactivation due to coking is a major problem. Based on the results obtained, addition of suitable chemical additives in the feed could alleviate this problem to a significant level and help in improving catalyst life cycle. 2016 Hydrogen Energy Publications LLC This publication was made possible by UREP grant ( UREP17-047-2-015 ) from the Qatar National Research Fund (a member of Qatar foundation). The statements made herein are solely the responsibility of the author(s). Scopus

Cobalt oxides nanopowders were prepared using novel cellulose assisted combustion synthesis and solution combustion synthesis techniques. The synthesis conditions were optimized to produce high surface area cobalt oxide nanopowders. Effect of precursors ratio on product properties (such as crystalline structure, nanoparticle size, surface area etc.) were studied and compared for the two methods. Thermodynamic calculations along with TGA/DTA studies were used to understand the synthesis mechanism leading to cobalt oxide formation. The synthesized nanopowders were characterized using various materials characterization techniques such as XRD, SEM and TEM. Qatar Foundation;Qatar National Research Fund Scopus