水素燃料電池におけるペロブスカイトの酸素還元性能を向上させる新方策(英語版のみ)

2023年12月15日

東北大学材料科学高等研究所(WPI-AIMR)

A research group has reported on a new method to enhance the electrochemical surface area (ECSA) in a calcium-doped perovskite, La0.6Ca0.4MnO3 (LCMO64), thereby overcoming a common bottleneck in the application of perovskite oxides as electrocatalysts in hydrogen fuel cells.

Details of the findings were reported in the journal Advanced Materials on November 29, 2023.

Perovskite oxides exhibit interesting and diverse properties, making them valuable in various technological applications. Their high intrinsic activities also position them as a promising alternative to noble metal catalysts for efficiently catalyzing the oxygen reduction reaction (ORR). However, their application is still hampered by their poor electrical conductivity and low specific surface area.

“Our electrochemically induced calcium-leaching process greatly increased ECSA in LCMO64,” points out Hao Li, Associate Professor at Tohoku University's Advanced Institute for Materials Research (WPI-AIMR) and corresponding author of the paper. “The activated, calcium-deficient LCMO64 demonstrated an ECSA approximately 33.84% higher than that of unactivated materials, showcasing superior electrocatalytic ORR performance—surpassing the benchmark commercial Pt/C catalyst in an alkaline solution.”

Evidence of calcium leaching during ORR, leading to the high surface area of the LCMO64. ©Hao Li et al.

To test the benchmarks of the material, Li and his colleagues conducted theoretical analysis along with electrochemical surface state probing and pH-dependent microkinetic modeling. The results suggested that this catalyst reaches the Sabatier optimum of alkaline ORR.

The electrochemical performance. ©Hao Li et al.

This research marks the first time a strategy involving calcium (Ca) doping has been employed to overcome challenges associated with low conductivity and surface area in perovskite oxides. The unique phenomenon of Ca leaching observed under ORR conditions results in a higher surface roughness, significantly expanding the available surface area for ORR and thereby boosting the catalyst's performance.

“Finding low-cost and effective electrocatalysts for the ORR in hydrogen fuel cells has been a significant challenge,” adds Li. “Our work not only addresses this challenge but also offers a novel strategy for enhancing the electrocatalytic performance of perovskite oxides. This breakthrough has far-reaching implications for the widespread adoption of hydrogen fuel cell technology.”

State-of-the-art theoretical analyses of ORR activities on the materials. ©Hao Li et al.

論文情報

論文タイトル: Cation-Deficient Perovskites Greatly Enhance the Electrocatalytic Activity for Oxygen Reduction Reaction
著者: Qun Li, Di Zhang, Jiabin Wu*, Simin Dai, Heng Liu, Min Lu, Renwen Cui, Wenxi Liang, Dingsheng Wang, Pinxian Xi*, Meilin Liu, Hao Li*, Liang Huang*
雑誌名: Advanced Materials
DOI番号: 10.1002/adma.202309266新しいタブで開きます

問い合わせ先

研究に関すること

東北大学材料科学高等研究所(WPI-AIMR)
Hao Li

E-mail: li.hao.b8@tohoku.ac.jp
Webstie: Hao Li Laboratory新しいタブで開きます

報道に関すること

東北大学材料科学高等研究所(WPI-AIMR) 広報戦略室

Tel: 022-217-6146
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