Inorganic Chemistry, Vol.57, No.4, 1815-1823, 2018
Synthesis and Electrocatalytic Activity of Ammonium Nickel Phosphate, [NH4]NiPO4 center dot 6H(2)O, and beta-Nickel Pyrophosphate, beta-Ni2P2O7: Catalysts for Electrocatalytic Decomposition of Urea
Electrocatalytic decomposition of urea for the production of hydrogen, H-2, for clean energy applications, such as in fuel cells, has several potential advantages such as reducing carbon emissions in the energy sector and environmental applications to remove urea from animal and human waste facilities. The study and development of new catalyst materials containing nickel metal, the active site for urea decomposition, is a critical aspect of research in inorganic and materials chemistry. We report the synthesis and application of [NH4]NiPO4 center dot 6H(2)O and beta-Ni2P2O7 using in situ prepared [NH4](2)HPO4. The [NH4]NiPO4 center dot 6H(2)O is calcined at varying temperatures and tested for electrocatalytic decomposition of urea. Our results indicate that [NH4]NiPO4.6H(2)O calcined at 300 degrees C with an amorphous crystal structure and, for the first time applied for urea electrocatalytic decomposition, had the greatest reported electroactive surface area (ESA) of 142 cm(2)/mg and an onset potential of 0.33 V (SCE) and was stable over a 24-h test period.