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A Porous Perovskite Nanofiber with Reinforced Aerophobicity for High-Performance Anion Exchange Membrane Water Splitting |
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| Authors: | Lu Li Zhilin Zheng Jiaxing Li Yongbiao Mu Yameng Wang Zebing Huang Yiping Xiao Haitao Huang Shuai Wang Gao Chen Lin Zeng |
| Affiliation: | 1. Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055 China Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, 999077 China;2. Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055 China;3. Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055 China SUSTech Energy Institute for Carbon Neutrality, Southern University of Science and Technology, Shenzhen, 518055 China;4. Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, 999077 China |
| Abstract: | Perovskite oxides stand out as emerging oxygen evolution reaction (OER) catalysts on account of their effective electrocatalytic performance and low costs. Nevertheless, perovskite oxides suffer from severe bubble overpotential and inhibited electrochemical performance in large current densities due to their small specific surface areas and structural compactness. Herein, the study highlights the electrospun nickel-substituted La0.5Sr0.5FeO3-δ (LSF) porous perovskite nanofibers, that is, La0.5Sr0.5Fe1-xNixO3-δ (denoted as ES-LSFN-x, x = 0, 0.1, 0.3, and 0.5), as high-performance OER electrocatalysts. The most effective La0.5Sr0.5Fe0.5Ni0.5O3-δ (ES-LSFN-0.5) nanofibers suggest a larger specific surface area, higher porosity, and faster mass transfer than the counterpart sample prepared by conventional sol–gel method (SG-LSFN-0.5), showing notably increased geometric and intrinsic activities. The bubble visualization results demonstrate that the enriched and nano-sized porosity of ES-LSFN-0.5 enables reinforced aerophobicity and rapid detachment of oxygen bubbles, thereby reducing the bubble overpotential and enhancing the electrochemical performance. As a result, the ES-LSFN-0.5-based anion exchange membrane water electrolysis delivers a superior stability of 100 h while the SG-LSFN-0.5 counterpart degrades rapidly within 20 h under a current density of 100 mA cm−2. The results highlight the advantage of porous electrocatalysts in optimizing the performance of large current density water electrolysis devices by reducing the bubble overpotential. |
| Keywords: | anion exchange membrane water electrolysis electrospinning oxygen evolution reaction perovskite oxide porous nanofibers |