Nickel(0) nanoparticles supported on bare or coated cobalt ferrite as highly active, magnetically isolable and reusable catalyst for hydrolytic dehydrogenation of ammonia borane

Manna, Joydev
Özkar, Saim
Nickel(0) nanoparticles supported on cobalt ferrite (Ni-0/CoFe2O4), polydopamine coated cobalt ferrite (NP0/PDA-CoFe2O4) or silica coated cobalt ferrite (NP0/SiO2-CoFe2O4) are prepared and used as catalysts in hydrogen generation from the hydrolysis of ammonia borane at room temperature. Ni-0/CoFe2O4 (4.0% wt. Ni) shows the highest catalytic activity with a TOF value of 38.3 min(-1) in hydrogen generation from the hydrolysis of ammonia borane at 25.0 +/- 0.1 degrees C. However, the initial catalytic activity of Ni-0/NCoFe204 catalyst is not preserved in subsequent runs of hydrolysis. Coating the surface of cobalt ferrite support with polydopamine or silica leads to a significant improvement in the stability of catalysts. The TOF values of Ni-0/PDA-CoFe2O4 and Ni-0/(2)-CoFe2O4 are found to be 7.6 and 5.3 min(-1), respectively, at 25.0 +/- 0.1 degrees C. Ni-0/PDA-CoFe2O4 catalyst shows high reusability as compared to the Ni-0/CoFe2O4 and NP0/SiO2-CoFe2O4 catalysts in hydrolytic dehydrogenation of ammonia borane at room temperature. All the catalysts are characterized by using a combination of various advanced analytical techniques. The results reveal that nickel nanoparticles with an average size of 12.3 +/- 0.7 nm are well dispersed on the surface of PDA-CoFe2O4.


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Citation Formats
J. Manna, S. AKBAYRAK, and S. Özkar, “Nickel(0) nanoparticles supported on bare or coated cobalt ferrite as highly active, magnetically isolable and reusable catalyst for hydrolytic dehydrogenation of ammonia borane,” JOURNAL OF COLLOID AND INTERFACE SCIENCE, pp. 359–368, 2017, Accessed: 00, 2020. [Online]. Available: