Thermochemical two-step water splitting cycle using Ni-ferrite and CeO 2 coated ceramic foam devices by concentrated Xe-light radiation

Abstract

Nickel ferrite (NiFe2O4) and pure cerium oxide (CeO2) supported on monoclinic zirconia (NiFe2O 4/m-ZrO2) are proposed as promising redox materials for the production of hydrogen from water via a thermochemical two-step water splitting cycle. Ceramic foam devices coated with NiFe2O 4/m-ZrO2 or pure CeO2 particles are prepared as a receiver/reactor operating a thermochemical water splitting cycle to produce hydrogen. The foam devices are examined in a directly irradiated receiver/reactor by a sun simulator on a laboratory scale. The purpose of this study is to examine the evolution of oxygen and hydrogen during the cyclization reaction different thermal-reduction (T-R) temperatures of 1450 and 1550 °C, and to compare the reproducible and stoichiometric oxygen/hydrogen production for both foam devices through a repeatable two-step reaction. In this study, a zirconia ceramic foam was used as a matrix for the reacting materials of NiFe2O4/m-ZrO2 or CeO2 particles. The zirconia ceramic foam has a diameter of 60 mm, a thickness of 15 mm, and a porosity of 10 cpi (cell number per linear inch). The loading amounts of reacting materials are 5 wt% for NiFe2O4/m-ZrO2 and 40 wt% for CeO2 particles. A concentrated Xe-beam is radiated to the foam device in a N2 stream for the T-R step and in a N 2/steam gas mixture for the subsequent water-decomposition (W-D) step. © 2013 The Authors.