Hydrogen Generation from Thermochemical Water-Splitting Using Core-Shell Ni-Ferrite Nanoparticles

摘要

During thermochemical water-splitting process for hydrogen generation, ferrite nanoparticles undergo significant grain growth that reduces their surface area and affect the porous morphology. Consequently, hydrogen volume generation increase in thermochemical cycles. In order to mitigate the grain growth, we have encapsulated the ferrite nanoparticles with porous shell of thermally stable ceramic material. Ni-ferrite nanoparticles were synthesized using the sol-gel further utilized to prepare core-shell nanoparticles with ZrO_2 or Y_2O_3. As-prepared core-shell NiFe_2O_4/ZrO_2 nanoparticles were analyzed by powdered X-Ray diffraction, transmission electron microscopy (TEM) and BET specific surface area analyzer. TEM analysis indicated core-shell morphology with Ni-ferrite encapsulated inside ZrO_2 shell of average thickness of 6.12 nm. Core-shell Ni-ferrite/ZrO_2 nanoparticles were loaded in Inconel reactor and five consecutive thermochemical ere performed at 900°– 1100°C for hydrogen generation. The results indicated relatively steady hydrogen volume generation in multiple thermochemical cycles.