Cobalt-based ferrites as efficient redox materials for thermochemical two-step CO2-splitting: enhanced performance due to cation diffusion. Issue 4 (19th February 2019)

• Record Type: Journal Article
• Authors: Huang, Jincheng; Fu, Yu; Li, Shuqing; Kong, Wenbo; Zhang, Jun; Sun, Yuhan
• Is Part Of: Sustainable energy & fuels. Volume 3:Issue 4(2019)
• Page Start: 975
• Page End: 984
• Publication Date: 2019-02-19
• Subjects: Renewable energy sources -- Periodicals; Fuel cells -- Periodicals; Electric batteries -- Periodicals; Electrochemistry -- Periodicals; 660.297
• DOI: 10.1039/c8se00611c
• Languages: English
• ISSNs: 2398-4902

Abstract

Abstract : The addition of CoO into CoFe2 O4 triggers bulk cation diffusion and thereby leads to higher CO2 splitting reactivity. Abstract : Thermochemical two-step CO2 splitting under concentrated solar energy has received significant attention, and ferrites are promising materials for such a redox reaction. However, their application is still challenged by the sintering problem due to the inevitably high operating temperature. Herein, we report non-stoichiometric cobalt-based ferrites, with no thermostable supports employed, as efficient redox materials for thermochemical two-step CO2 splitting. In comparison with ZrO2 - and Al2 O3 -added CoFe2 O4, CoO-added CoFe2 O4 (CoFe2 O4 /CoO) shows a CO productivity of 8.5 mL g −1, which is 1.5 and 3.2 times higher than that of CoFe2 O4 /ZrO2 (5.4 mL g −1 ) and CoFe2 O4 /Al2 O3 (2.6 mL g −1 ), respectively. Based on the morphological and crystal structure characterization by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Mössbauer spectroscopy and Fourier transform infrared spectroscopy (FT-IR), the ferrites were thoroughly analyzed and thereby bulk cation diffusion for CoFe2 O4 /CoO over the reaction is kinetically demonstrated to play an important role in enhancing the performance.