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A novel, nitrate-free, combustion method has been developed to prepare Ni-BaZr 0.85 Y 0.15 O 32d (Ni-BZY) cermet anodes for proton ceramic fuel cells. Nickel acetate and 30% H 2 O 2 were used as starting precursors for the combustion reaction into which pre-prepared BZY powders were dispersed. The advantages of this nitrate-free combustion method have been demonstrated by comparison to a more common nitrate/ glycine combustion route. The results demonstrate that use of the nitrate-free precursors is essential to avoid partial decomposition of the pre-prepared BZY phase. Employment of the more common nitratebased precursors, due to their acidic nature, results in removal of Ba from the perovskite phase and formation of Ba(NO 3 ) 2 , subsequently leading to the presence of BaY 2 NiO 5 in the final product. The impact of Ni-BZY phase purity on resultant polarisation behaviour has been assessed as a function of water vapour and oxygen partial pressures for electrodes of comparable microstructure. Partial decomposition of the perovskite phase limits performance by increasing the higher frequency polarisation resistance and this phenomenon is suggested to be associated with impaired proton transport in the oxide cermet phase. The novel actetate-H 2 O 2 combustion method here described may be of interest for the formation of other ceramic oxide materials, offering economical advantages over more classical nitrate-based combustion routes, as well as significant environmental benefits due to the avoidance of releasing NO x gases.

Considering the expected increasing demand for cellulose fibers in the near future and that its major source is wood pulp, alternative sources such as vegetable wastes from agricultural activities and agro-food industries are currently being sought to prevent deforestation. In the present study, cellulose was successfully isolated from six agroindustrial residues: corncob, corn husk, grape stalk, pomegranate peel, marc of strawberry-tree fruit and fava pod. Cellulose fibers were characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis, stereomicroscopy and scanning electron microscopy (SEM). Despite the evident morphological differences among the extracted celluloses, results revealed similar compositional and thermal properties with the wood-derived commercial microcrystalline cellulose used as a control. Trace amounts of lignin or hemicellulose were detected in all cellulose samples, with the exception of corncob cellulose, that exhibited the greatest extraction yield (26%) and morphological similarities to wood-derived microcrystalline cellulose, visible through SEM. Furthermore, corncob cellulose was found to have thermal properties (TOnset of 307.17 °C, TD of 330.31 °C, and ΔH of 306.04 kJ/kg) suitable for biomedical applications.

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