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Browsing by Author "Wang, Wei"

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  • Evaluation of the CO2 Tolerant Cathode for Solid Oxide Fuel Cells: Praseodymium Oxysulfates/Ba0.5Sr0.5Co0.8Fe0.2O3-δ
    Publication . Yang, Tao; Su, Chao; Wang, Wei; Meng, Lijian; Deng, Jiguang; Liu, Yu; Rathore, Shambhu; Shao, Zongping
    An effective praseodymium oxysulfate/Ba0.5Sr0.5Co0.8Fe0.2O3-δ composite cathode with high stability in 10% CO2/air was investigated. The addition of 50 vol.% of the praseodymium oxysulfate shows much better tolerance to CO2, and reduced the polarization resistance of the cathode to 1/3 comparing with that of Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF). The CO2–temperature programmed desorption (TPD) and the electrochemical impedance spectroscopy (EIS) proved the effectiveness of the praseodymium oxysulfate phase to reduce the electrode resistance and to improve the CO2 resistance. The coefficient thermal expansion (CTE) rate along with the different volume percentage of praseodymium oxysulfate was also measured and it was found that the praseodymium oxysulfate helps to regulate the total CTE of the composite to match with doped-ceria electrolyte. It is proposed the higher acidity of Pr3+/4+ cations inhibited the reaction of alkaline earth metal oxide to form carbonates on the surface of the BSCF particles. The above results proved praseodymium oxysulfate/Ba0.5Sr0.5Co0.8Fe0.2O3-δ to be a highly active and stable cathode for solid oxide fuel cells.
    2018-07-26Journal article Restricted access Show more
  • Sulfur and phosphorus co-doped FeCoNiCrMn high-entropy alloys as efficient sulfion oxidation reaction catalysts enabling self-powered asymmetric seawater electrolysis
    Publication . Yu, Zhipeng; Boukhvalov, Danil W.; Tan, Hao; Xiong, Dehua; Feng, Chuangshi; Wang, Jingwei; Wang, Wei; Zhao, Yang; Xu, Kaiyang; Su, Weifeng; Xiang, Xinyi; Lin, Fei; Huang, Haoliang; Zhang, Fuxiang; Zhang, Lei; Meng, Lijian; Liu, Lifeng
    Seawater electrolysis (SWE) represents a promising approach to green hydrogen (H2) production but currently faces substantial challenges such as the interference of chlorine chemistry and high energy consumption. In this work, we demonstrate that by replacing the energy-demanding oxygen evolution reaction (OER) with the sulfion oxidation reaction (SOR) and by implementing the concept of bipolar membrane (BPM) electrolysis in an acid-base dual electrolyte system, not only can the notorious chlorine evolution reaction (CER) be completely circumvented, but the energy consumption of SWE be significantly reduced. To do so, we develop a sulfur and phosphorus co-doped FeCoNiCrMn high entropy alloy (HEA-SP) catalyst, which shows good electrocatalytic performance for the SOR in alkaline-saline water. This can be attributed to the abundant lattice defects and strains in HEA-SP, leading to a high density of active sites and an optimized electronic structure favorable for the SOR. Moreover, density functional theory calculations and in situ Raman spectroscopy characterization reveal the crucial role of imperfect sulfur coverage on the HEA in facilitating the formation of Sx clusters during the SOR. Using the HEA-SP as anode catalysts, the SOR-assisted SWE only needs electrical energy of 0.253 kWh to produce one cubic meter of H2 at 100 mA cm−2, in the presence of a BPM. Impressively, chlorine-free H2 production from seawater and upgrading of sulfions to valuable sulfur can occur simultaneously and spontaneously at 10 mA cm−2, highlighting the great potential of the HEA-SP catalysts and the asymmetric cell design to enable energy- and cost-effective seawater electrolysis.
    2024Journal article Restricted access Show more