Enhanced catalytic performance in hydrogen generation from NaBH4 hydrolysis by super porous cryogel supported Co and Ni catalysts
Yükleniyor...
Tarih
2014
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
The neutral 3-D superporous cryogel is prepared from a poly(acrylamide) (p(AAm)) hydrogel network modified with an amidoximation reaction to induce chemical changes to produce superporous amidoximated-p(AAm) (amid-p(AAm)) cryogel. The newly-formed strongly ionizable matrices can readily absorb metal ions such as Co(II) and Ni(II) enabling in situ preparation of corresponding metal nanoparticles by NaBH4 treatments. It is found that the superporous amid-p(AAm)-Co cryogel composite is very effective as a catalyst for H-2 generation from hydrolysis of NaBH4 in alkaline medium. Furthermore, it is demonstrated that the metal ion loading capacity and catalytic activity of superporous amid-p(AAm)-Co cryogel composites increased with 2nd and 3rd Co(II) ion loading and reduction cycles. The hydrogen generation rate of p(AAm)-Co metal composites is increased to 1926.3 +/- 1.1 from 1130.2 +/- 1.5 (mL H-2) (min)(-1) (g of M)(-1). The effect of various parameters such as porosity, metal type, the number of reloading and reduction cycles of the metal ion, and temperature are investigated for the hydrolysis of NaBH4. The kinetic parameters such as energy, enthalpy and entropy are determined as Ea = 39.7 +/- 0.2 kJ mol(-1), Delta H = 37.2 +/- 0.1 kJ mol(-1) and Delta S = -171.9 +/- 0.5 J mol(-1) K-1, respectively. (C) 2014 Elsevier B.V. All rights reserved.
Açıklama
Anahtar Kelimeler
Super-porous cryogel, Microstructured hydrogel, Cryogel/hydrogel template, Composite, H-2 generation
Kaynak
Journal of Power Sources
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
272
