低温で水素生成を可能にする水分解触媒を開発 (Water splitting catalyst creates hydrogen at low temperatures)

2026-05-01 バーミンガム大学

＜関連情報＞

• https://www.birmingham.ac.uk/news/2026/water-splitting-catalyst-creates-hydrogen-at-low-temperatures
• https://www.sciencedirect.com/science/article/abs/pii/S036031992505640X

水素製造のためのBa2Ca0.66 Nb1.34- xFexO 6- δペロブスカイト上での中温における顕著な熱化学的水分 Remarkable thermochemical water-splitting on Ba2Ca0.66Nb1.34-xFexO6-δ perovskites at medium temperatures for hydrogen production

Biduan Chen, Wenyi Huang, Wei Guo, Lige Tong, Yulong Ding, Li Wang
International Journal of Hydrogen Energy
DOI:https://doi.org/10.1016/j.ijhydene.2025.152637

Graphical abstract

Highlights

• Water splitting of Ba₂Ca_0.66Nb_1.34-xFe_xO₆ at moderate temperatures was evaluated.
• Impacts of operation mode, reduction temperature and steam pressure were studied.
• Average H₂ yield of 10 cycles was 1014 μmol/g, and the structure remained stable.
• Oxygen vacancy between Ca and Fe atoms is active sites for water splitting.
• H₂O molecules undergo dissociative adsorption at Fe-V_O-Ca oxygen vacancy sites.

Abstract

Recent literature reports on two-step thermochemical water splitting on metal oxides present a promising pathway for sustainable H₂ production. However, these processes require a high reduction temperature of ∼1300–1500 °C, which poses a significant challenge in material stability, reactor design, and practical operations. The development of cost-effective materials for such a pathway, which are capable of operating at lower temperatures, becomes a research frontier. Here, we present a recent study on thermochemical H₂O splitting on Ba₂Ca_0.66Nb_1.34-xFe_xO_6-δ (x = 0.34, 0.66, 1), showing the potential for medium-temperature water splitting. The impacts of operating modes, reduction temperature, and water partial pressures on H₂ production were investigated. Ba₂Ca_0.66Nb_0.34FeO_6-δ exhibited the highest thermochemical reactivity, producing ∼100 μmol/g of H₂ over isothermal cycles at 700 °C. Notably, a significant increase in H₂ yield was observed at a lower oxidation temperature. Over 10 cycles of thermal reduction at 1000 °C followed by the cooling-oxidation (1000-150 °C, 0.0419 atm of water partial pressure), an average H₂ yield of 1014.22 μmol/g was achieved. The results provide evidence of effective H₂ production capabilities of the material at a moderate temperature, demonstrating the promising pathway towards low-temperature H₂ production via thermochemical splitting cycles.