Electrospun NiPd Nanoparticles Supported on Polymer Membrane Nanofibers as an Efficient Catalyst for NaBH4 Dehydrogenation

Abstract

Sodium borohydride (SBH) hydrolysis in the presence of cheap and efficient catalysts has been proposed as a safe and efficient method for generating clean hydrogen energy for use in portable applications. In this work, we synthesized bimetallic NiPd nanoparticles (NPs) supported on poly(vinylidene fluoride-co-hexafluoropropylene) nanofibers (PVDF-HFP NFs) via the electrospinning approach and reported an in-situ reduction procedure of the NPs being prepared by alloying Ni and Pd with varying Pd percentages. The physicochemical characterization provided evidence for the development of a NiPd@PVDF-HFP NFs membrane. The bimetallic hybrid NF membranes exhibited higher H2 production as compared to Ni@PVDF-HFP and Pd@PVDF-HFP counterparts. This may be due to the synergistic effect of binary components. The bimetallic Ni1−xPdx(x = 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3)@PVDF-HFP nanofiber membranes exhibit composition-dependent catalysis, in which Ni75Pd25@PVDF-HFP NF membranes demonstrate the best catalytic activity. The full H2 generation volumes (118 mL) were obtained at a temperature of 298 K and times 16, 22, 34 and 42 min for 250, 200, 150, and 100 mg dosages of Ni75Pd25@PVDF-HFP, respectively, in the presence of 1 mmol SBH. Hydrolysis utilizing Ni75Pd25@PVDF-HFP was shown to be first order with respect to Ni75Pd25@PVDF-HFP amount and zero order with respect to the [NaBH4] in a kinetics study. The reaction time of H2 production was reduced as the reaction temperature increased, with 118 mL of H2 being produced in 14, 20, 32 and 42 min at 328, 318, 308 and 298 K, respectively. The values of the three thermodynamic parameters, activation energy, enthalpy, and entropy, were determined toward being 31.43 kJ mol−1, 28.82 kJ mol−1, and 0.057 kJ mol−1 K−1, respectively. It is simple to separate and reuse the synthesized membrane, which facilitates their implementation in H2 energy systems.