Table 1. Textural Properties of the Fresh Calcined and Reduced Catalysts.

	SBETa (m2/g)		Vpa (cm3/g)		Dpa (nm)								Ni/Fe molar ratio in alloyh
catalyst	fresh	reduced	fresh	reduced	fresh	reduced	crystalline sizeb (nm)	particle sizec (nm)	H2 consumptiond (mmol/g)	reduction degreee (%)	basicityf (mmol/g)	surface Ni/Fe atomic ratiog	reduced	spent
Ni1Fe1	207.1	153.7	0.75	0.82	14.2	20.5	9.2	10.28	4.23	87.8	0.182	0.38	1.14	1.76
Ni2Fe1	217.3	162.3	0.72	0.80	13.2	18.1	10.6	10.75	4.08	91.0	0.174	0.76	2.11	2.44
Ni3Fe1	219.4	160.0	0.61	0.86	10.4	20.6	10.2	10.80	3.89	90.0	0.168	0.90	3.04	3.62
Ni4Fe1	211.3	166.1	0.63	0.71	11.2	16.7	9.5	10.69	3.69	87.4	0.373	1.16	3.96	4.13
Ni1Fe0	181.4	143.6	0.44	0.48	9.2	12.7	12.6	16.90	3.34	87.2	0.186

^aCalculated from N₂ isotherms at 77 K.

^bCalculated from XRD patterns using the Debye–Scherrer equation.

^cDetermined by the FETEM images.

^dH₂ consumption below 800 °C, determined by the H₂-TPR profiles in Figure 2a.

^eDetermined by the ratio of actual H₂ consumption to stoichiometric H₂ consumption. The stoichiometry of the Ni and Fe reductions is Ni²⁺ + H₂ → Ni⁰ + 2H⁺ and Fe³⁺ + 3/2H₂ → Fe⁰ + 3H⁺, respectively.

^fDetermined by the CO₂-TPD profiles in Figure 2b.

^gAtomic ratios of Ni and Fe on the surface of the reduced catalyst determined by XPS.

^hAtomic ratios of Ni and Fe in alloy particles determined by the d(2 0 0) spacing derived from XRD and Vegard’s law (Figure 1a).