{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:10:08Z","timestamp":1792789808466,"version":"4.5.0"},"reference-count":27,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T00:00:00Z","timestamp":1789862400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["22178269"],"award-info":[{"award-number":["22178269"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"crossref"}]},{"name":"National Natural Science Foundation of China","award":["22178271"],"award-info":[{"award-number":["22178271"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"crossref"}]},{"name":"National Natural Science Foundation of China","award":["22208009"],"award-info":[{"award-number":["22208009"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"crossref"}]},{"award":["22178269"],"award-info":[{"award-number":["22178269"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"award":["22178271"],"award-info":[{"award-number":["22178271"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"award":["22208009"],"award-info":[{"award-number":["22208009"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"S&T Program of Hebei","award":["246Z4602G"],"award-info":[{"award-number":["246Z4602G"]}]},{"name":"Cangzhou Institute of Tiangong University","award":["TGCYY-F-0104"],"award-info":[{"award-number":["TGCYY-F-0104"]}],"id":[{"id":"https:\/\/ror.org\/00xsr9m91","id-type":"ROR","asserted-by":"crossref"}]},{"award":["TGCYY-F-0104"],"award-info":[{"award-number":["TGCYY-F-0104"]}],"id":[{"id":"https:\/\/ror.org\/00xsr9m91","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Natural Science Foundation of Cangzhou","award":["23241002006N"],"award-info":[{"award-number":["23241002006N"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Membranes"],"abstract":"<jats:p>A series of Ba-excess BaxCe0.7Zr0.1Y0.1Yb0.1O3\u2212\u03b4 (BxCZYYb, x = 1.05, 1.10, 1.15) was employed as electrolytes. Multilayer microtubular protonic ceramic electrochemical hydrogen pumps (PCEHPs) with a current collector\/anode\/electrolyte\/cathode\/current collector architecture were fabricated by a triple-layer one-step co-spinning and co-sintering method. Their hydrogen separation performance was systematically investigated over the temperature range of 200\u2013400 \u00b0C. The results show that the hydrogen pump employing the B1.05CZYYb electrolyte delivers the optimal performance. At 250 \u00b0C and a feed H2 concentration of 30 vol%, the hydrogen permeation flux achieves 1.01 mL min\u22121 cm\u22122, with Faradaic efficiency maintained above 95%. EDS line-scan results reveal the presence of Ni-rich precipitates on grain surfaces in the co-sintered electrolyte layer. It is speculated that, under the co-sintering conditions, excessive Ba may induce lattice distortion and reduce Ni solubility in the perovskite lattice, thereby promoting Ni exsolution at grain surfaces; the precipitated Ni could, in turn, hinder proton conduction and increase the ohmic resistance. These findings suggest that the hydrogen-permeation performance of multilayer PCEHPs is governed by the combined effect of Ba excess and Ni rather than by Ba doping alone. This work provides a valid experimental basis and theoretical reference for component optimization and structural design of high-performance co-sintered microtubular PCEHP devices.<\/jats:p>","DOI":"10.3390\/membranes16090307","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T12:50:03Z","timestamp":1789995003000},"page":"307","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effects of Barium Excess on the Performance of Multilayer Microtubular Proton Ceramic Electrochemical Hydrogen Pumps with BaxCe0.7Zr0.1Y0.1Yb0.1O3\u2212\u03b4 (x = 1.05, 1.10, 1.15)"],"prefix":"10.3390","volume":"16","author":[{"given":"Shao","family":"Zhang","sequence":"first","affiliation":[{"name":"State Key Laboratory of Advanced Separation Membrane Materials, College of Chemical Engineering and Technology, Tiangong University, Tianjin 300387, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"given":"Lihui","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Separation Membrane Materials, College of Chemical Engineering and Technology, Tiangong University, Tianjin 300387, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"data-curation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"given":"Congcong","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Separation Membrane Materials, College of Chemical Engineering and Technology, Tiangong University, Tianjin 300387, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"}]},{"given":"Mingming","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Separation Membrane Materials, College of Chemical Engineering and Technology, Tiangong University, Tianjin 300387, China"},{"name":"Hebei Industrial Technology Research Institute of Membranes, Cangzhou Institute of Tiangong University, Cangzhou 061000, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Zhigang","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Separation Membrane Materials, College of Chemical Engineering and Technology, Tiangong University, Tianjin 300387, China"},{"name":"Hebei Industrial Technology Research Institute of Membranes, Cangzhou Institute of Tiangong University, Cangzhou 061000, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2704-8018","authenticated-orcid":false,"given":"Xiaoyao","family":"Tan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Separation Membrane Materials, College of Chemical Engineering and Technology, Tiangong University, Tianjin 300387, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"116378","DOI":"10.1016\/j.rser.2025.116378","article-title":"Hydrogen power development: A comparative review of national strategies and the role of energy in scaling green hydrogen","volume":"226","author":"Konovalov","year":"2026","journal-title":"Renew. 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