Authors: R. Bhosale, R. Shende, J. Puszynski
Affilation: South Dakota School of Mines & Technology, United States
Pages: 368 - 371
Keywords: H2 generation, thermochemical water-splitting, sol-gel, ferrite foamte foam
Ferrites in the form of spinel, doped spinel, and wustite are used for H2 generation from thermochemical water-splitting reaction. Although these ferrites have been synthesized by solid-state mixing, self-propagation high temperature synthesis and aerosol-spray pyrolysis methods, the use of sol-gel derived ferrites for thermochemical water-splitting reaction is very limited. In this study, Ni-ferrite was synthesized by the sol-gel method wherein the addition of propylene oxide (PO) in a precursor solution containing Ni2+ and Fe2+ ions in ethanol produced a gel, which was later calcined in air or N2 environment. The H2 production abilities of Ni-ferrites with different phase compositions were investigated. In addition, Sn-doped Ni-ferrite was also synthesized using surfactant templating sol-gel approach involving the addition of polymer microspheres. The gel containing these microspheres was rapidly heated in a microwave furnace to 1100oC and quenched. Powder X-ray diffraction, scanning electron microscopy (SEM), and BET surface area analysis were performed to characterize the different ferrite materials. SEM studies revealed ferrites with foam like morphology. On average the sol-gel derived Ni-ferrite produced 31 ml H2/g in four thermochemical cycles at 800oC. This presentation will focus on both synthesis and characterization of ferrites and H2 generation and regeneration cycles in a water-splitting reactor.