A novel CeO2–xSnO2/Ce2Sn2O7 pyrochlore cycle for enhanced solar thermochemical water splitting. Issue 8 (17th March 2017)

• Record Type: Journal Article
• Authors: Ruan, Chongyan; Tan, Yuan; Li, Lin; Wang, Junhu; Liu, Xiaoyan; Wang, Xiaodong
• Is Part Of: AIChE journal. Volume 63:Issue 8(2017)
• Page Start: 3450
• Page End: 3462
• Publication Date: 2017-03-17
• Subjects: solar fuel -- pyrochlore -- stoichiometric -- water splitting -- H2 production; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; 660.28
• DOI: 10.1002/aic.15701
• Languages: English
• ISSNs: 0001-1541

Abstract

Abstract : A novel CeO2 –xSnO2 /Ce2 Sn2 O7 pyrochlore stoichiometric redox cycle with superior H2 production capacities is identified and corroborated for two‐step solar thermochemical water splitting (STWS). During the first thermal reduction step (1400°C), a reaction between CeO2 and SnO2 occurred for all the CeO2 –xSnO2 (x = 0.05–0.20) solid compounds, forming thermodynamically stable Ce2 Sn2 O7 pyrochlore rather than metastable CeO2‐δ . Consequently, substantially higher reduction extents were achieved owing to the reduction of Ce IV to Ce III . Moreover, in the subsequent reoxidation with H2 O (800°C), H2 production capacities increased by a factor of 3.8 as compared to the current benchmark material ceria when x = 0.15, with the regeneration of CeO2 and SnO2 and the concomitant reoxidation of Ce III to Ce IV . The H2 O‐splitting performance for CeO2 –0.15SnO2 was reproducible over seven consecutive redox cycles, indicating the material was also robust . © 2017 American Institute of Chemical Engineers AIChE J, 63: 3450–3462, 2017