Improved dehydrogenation performance of NaAIH4 using NiFe2O4 nanoparticles

The dehydrogenation properties of commercial NaAlH4 ball milled with a NiFe2O4 nanoparticle catalyst have rarely been studied. In this work, temperature programmed desorption analysis indicates that the onset temperature of three dehydrogenation steps of NaAIH(4) + 3 mol% NiFe2O4 is 72,132 and 82 degrees C lower than those of as-milled NaAlH4, respectively. The dehydrogenation capacity of NaAIH4 could be significantly improved by adding NiFe2O4. Furthermore, NaAIH(4) + 3 mol% NiFe2O4 displays good cycle stability at 150 degrees C and only a slight capacity loss after five cycles. The apparent activation energies of NaAIH(4) + 3 mol% NiFe2O4 for the three dehydrogenation steps are 54.3, 73.1 and 113.1 kJ mol(-1), respectively, as determined by differential scanning calorimetry and Kissinger analysis. From the analysis of X-ray diffraction, the new phases after dehydrogenation are NaFeO2 and Al3Ni. The reaction between NiFe2O4 and NaAIH(4) during desorption is revealed. (C) 2017 Elsevier B.V. All rights reserved.