High temperature steam electrolysis is considered as a prospective technology for industrial scale hydrogen production as a valuable chemical for utilization e.g. in energetics, transportation or chemical industry. Through the intensive research in the past decade, significant progress has been achieved in matureness of this technology. However, there are still important obstacles to be overcome before reaching its large scale industrialization. Utilization of huge amounts of organic solvents during series solid oxide cells (SOCs) production can be given as a typical example. This problem becomes recently increasingly important due to the strong emphasis on the environmental issues. Due to the above mentioned reason, this study has focused on development of SOCs by tape casting method from water based slurries. In these slurries beside demineralized water used as solvent, gelatin was used as a natural water soluble binder. The hydrogen electrode supported planar “button” cells were successfully prepared in this way. The commonly accepted NiO/YSZ – YSZ – LSM/YSZ – LSM system was used. The electrochemical characteristics of SOCs prepared were determined by means of voltammetry and impedance spectroscopy under steam electrolysis conditions. Durability tests were accomplished as well. Beside electrochemical characteristics, morphology of the SOCs was analyzed by means of scanning electron microscopy. The main problem represented inhomogeneity of electrolyte layer thickness which, in turn, can lead to the problems with homogeneity of distribution of local current density across the active cell area. The solution of this problem consisting in modification of YSZ slurry preparation procedure was proposed. It was proved that well performing cells can be prepared by tape casting method using slurries prepared. Current densities up to 250 mA cm–2 were reached at a cell voltage of 1.2 V and temperature of 800 °C. These values are fully comparable to the SOCs prepared by means of traditional solvents.
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