Chemical Hydride Hydrolysis For H2 Production Via Co, Cu, Ni Metal Nanoparticles Prepared Within P(4-VP) Capsules

Poly(4-Vinyl pyridine) (p(4-VP)) and poly(4-Vinyl pyridine)-silica (p(4-VP)-S) were synthesized using micro emulsion polymerization. A capsule of p(4-VP) (cap-p(4-VP)) was prepared from p(4-VP)-S by removing silica moieties via HF treatment. Metal nanoparticles (MNPs) such as Co, Cu and Ni were prepared within the prepared polymeric particles, and tested for their catalytic performances in the hydrolysis of sodium borohydride (NaBH4) and ammonium borane (BH3NH3). Furthermore, the hydrolysis reactions were evaluated for various parameters such as MNP types as catalysts, morphology of support materials, the extent of NaOH, temperature, and the amounts of MNPs. It was found that cap-p(4- VP) containing Co nanoparticles as cap-p(4-VP)-Co provided better catalytic performances, and used to determine the activation energy (Ea), the enthalpy (ΔH), and the entropy (ΔS) for the NaBH4 hydrolysis reaction, and were found to be 23.38 ± 2.8 kJ mol-1, 20.26 ± 2.8 kJ mol-1, and -158.8 ± 8.6 kJ mol-1 K-1, respectively. The Hydrogen Generation Rate (HGR) and Turn Over Frequency (TOF) values were calculated 5.57 L H2 (g of catalyst min)-1 and 13.13 mol H2 (mol catalyst min)-1 for the hydrolysis of NaBH4 catalyzed by cap-p(4-VP)-Co. The BET surface areas of the particles were also measured and estimated as 18.86 m2 g-1, 24.64 m2 g-1and 52.89 m2 g-1 for p(4-VP), p(4-VP)-S and cap-p(4-VP) particles, respectively.