Ceramic proton conductors are promising materials for clean energy.In contrast to the conventional acceptor doping,donor doping into the oxides with intrinsic oxygen vacancies is a novel strategy to achieve the reduce...Ceramic proton conductors are promising materials for clean energy.In contrast to the conventional acceptor doping,donor doping into the oxides with intrinsic oxygen vacancies is a novel strategy to achieve the reduced proton trapping.Here,we report high proton conductivity(e.g.,0.01 S cm^(-1) at 320℃)and high chemical stability of pentavalent donor doped BaScO_(2.5),BaSc_(0.75)Nb_(0.25)O_(2.75).The high proton conductivity is attributable to high proton concentration and high proton diffusion coefficient.The high proton concentration is ascribed to a large amount of oxygen vacancies in BaSc_(0.75)Nb_(0.25)O_(2.75) and full hydration in hydrated BaSc_(0.75)Nb_(0.25)O_(2.75).The high proton diffusion coefficient is attributable to its low activation energy,suggesting reduced proton trapping due to the repulsion between the donor Nb^(5+)dopant and protons.The repulsion is clearly shown by the ab initio molecular dynamics simulations.展开更多
基金the project approval(JRR-3 proposal no.24609,J-PARC:proposal no.2024A0178 and 2020L0804)supported by JSPS KAKENHI Grant Numbers JP21K18182,JP23K04887,JP23H04618,and JP24H00041,Adopting Sustainable Partnerships for Innovative Research Ecosystem(ASPIRE)from the Japan Science and Technology Agency(JST)(grant JPMJAP2308)+1 种基金the Adaptable and Seamless Technology Transfer Program through Target-Driven R&D(A-STEP)from JST(grant JPMJTR22TC),the Institute for Solid State Physics,the University of Tokyo,and the GIMRT Program of the Institute for Materials Research,Tohoku University(202403-CNKXX-0030,202405-CNKXX-0036,202412-QBKNE-0008,202412-QBKNE-0009)K.S.acknowledges support from a JSPS Fellowship for Young Scientists,DC1(23KJ0953).
文摘Ceramic proton conductors are promising materials for clean energy.In contrast to the conventional acceptor doping,donor doping into the oxides with intrinsic oxygen vacancies is a novel strategy to achieve the reduced proton trapping.Here,we report high proton conductivity(e.g.,0.01 S cm^(-1) at 320℃)and high chemical stability of pentavalent donor doped BaScO_(2.5),BaSc_(0.75)Nb_(0.25)O_(2.75).The high proton conductivity is attributable to high proton concentration and high proton diffusion coefficient.The high proton concentration is ascribed to a large amount of oxygen vacancies in BaSc_(0.75)Nb_(0.25)O_(2.75) and full hydration in hydrated BaSc_(0.75)Nb_(0.25)O_(2.75).The high proton diffusion coefficient is attributable to its low activation energy,suggesting reduced proton trapping due to the repulsion between the donor Nb^(5+)dopant and protons.The repulsion is clearly shown by the ab initio molecular dynamics simulations.
