A novel thermomechanically stable LaF_3–CsH_5(PO_4)_2 composite electrolyte with high proton conductivity at elevated temperatures over 150 °C  

作　　者：Jie Xiong Yunjie Huang Jing Li Liying Ma Guoxiao Xu Zhao Liu Weiwei Cai Hansong Cheng 

机构地区：[1]Sustainable Energy Laboratory, Faculty of Materials Science and Chemistry, China University of Geosciences (Wuhan) [2]College of Chemistry, Chemical Engineering and Material Science, Zaozhuang University

出　　处：《Journal of Energy Chemistry》2019年第3期114-120,共7页能源化学（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.21703211,21503197 and 21473164);Fundamental Research Funds for the Central University,China University of Geosciences(Wuhan)(Nos.CUG150615 and CUG150627)

摘　　要：A facile strategy is introduced to upgrade thermomechanical stability of the cesium pentahydrogen diphosphate(CPD), which is the most efficient inorganic electrolyte among all solid proton conductors,by constructing P–OH···F hydrogen bonds with lanthanum fluoride(LaF_3). The optimal combination of the LaF_3–CPD composite electrolyte is found to be 1:2 in a molar ratio(LaF_3–CPD-2). LaF_3–CPD-2 composite maintains robust solid state, even at a temperature up to 200 °C, which is 50 °C higher than the melting temperature of CPD. Meanwhile, the considerable proton conductivity of CPD is achieved in the LaF_3–CPD-2 composite electrolyte due to the synergistic effect of the P–OH···F hydrogen bonds and the intrinsic proton conductive property of CPD. Last but not least, the LaF_3–CPD-2 composite manifests excellent conductivity durability at 150 °C and low humidity condition with sizeable proton conductivity of0.0262 S cm^(-1) after 60 h operation, implying that the LaF_3–CPD composite could be a promising candidate for intermediate temperature proton conductors.A facile strategy is introduced to upgrade thermomechanical stability of the cesium pentahydrogen diphosphate(CPD), which is the most efficient inorganic electrolyte among all solid proton conductors,by constructing P–OH···F hydrogen bonds with lanthanum fluoride(LaF_3). The optimal combination of the LaF_3–CPD composite electrolyte is found to be 1:2 in a molar ratio(LaF_3–CPD-2). LaF_3–CPD-2 composite maintains robust solid state, even at a temperature up to 200 °C, which is 50 °C higher than the melting temperature of CPD. Meanwhile, the considerable proton conductivity of CPD is achieved in the LaF_3–CPD-2 composite electrolyte due to the synergistic effect of the P–OH···F hydrogen bonds and the intrinsic proton conductive property of CPD. Last but not least, the LaF_3–CPD-2 composite manifests excellent conductivity durability at 150 °C and low humidity condition with sizeable proton conductivity of0.0262 S cm^(-1) after 60 h operation, implying that the LaF_3–CPD composite could be a promising candidate for intermediate temperature proton conductors.

关 键 词：Intermediate temperature fuel cell Hydrogen BOND CESIUM pentahydrogen DIPHOSPHATE LANTHANUM FLUORIDE THERMOMECHANICAL stability 

分 类 号：TB33[一般工业技术—材料科学与工程]