固体氧化物燃料电池钙钛矿阳极材料可以通过改性获得优异的催化活性,低的极化阻抗和稳定的抗积炭能力。在此,以立方相钙钛矿Pr_(0.4)Sr_(0.6)Co_(0.2)Fe_(0.7)Mo_(0.1)O_(3-δ)作为阳极前驱体,然后将CeO_(2)成功地浸渍到阳极的多孔结构...固体氧化物燃料电池钙钛矿阳极材料可以通过改性获得优异的催化活性,低的极化阻抗和稳定的抗积炭能力。在此,以立方相钙钛矿Pr_(0.4)Sr_(0.6)Co_(0.2)Fe_(0.7)Mo_(0.1)O_(3-δ)作为阳极前驱体,然后将CeO_(2)成功地浸渍到阳极的多孔结构中。通过原位还原技术获得了纳米合金粒子负载钙钛矿基底的复合阳极用于质子导体乙烷固体氧化物燃料电池。在氢气和乙烷气氛中,750℃时,燃料电池峰值功率密度分别达到253和183 m W·cm^(-2)。而且,在十小时的测试中燃料电池性能没有衰减反而电流密度随着时间的延长而增加,表明CeO_(2)浸渍表现出优异的催化活性和抗积炭稳定性。同时,通过产物分析,乙烯的产率从650℃下的23.52%增加到750℃下的34.09%,并且乙烯选择性超过94%。因此改性的阳极通过析出的纳米颗粒与CeO_(2)的协同作用,促进了燃料电池电极的催化活性和稳定性,将其运用到质子导体固体氧化物乙烷燃料电池中成功实现了乙烯与电能的共生。展开更多
Single-atomic site catalysts have drawn considerable attention because of their maximum atom-utilization efficiency and excellent catalytic activity.In this work,a highly active single-atomic Pt site photocatalyst was...Single-atomic site catalysts have drawn considerable attention because of their maximum atom-utilization efficiency and excellent catalytic activity.In this work,a highly active single-atomic Pt site photocatalyst was synthesized through employing defective Ti0_(2) nanosheets as solid support for photo-catalytic water splitting.It indicated that the surface oxygen vacancies on defective Ti0_(2) nanosheets could effectively stabilize the single-atomic Pt sites through constructing a three-center Ti-Pt-Ti structure.The Ti-Pt-Ti structure can hold the stability of isolated single-atomic Pt sites and facilitate the separation and transfer of photoinduced charge carriers,thereby greatly improving the photocatalytic H2 evolution.Notably,our synthesized photocatalyst exhibited a remarkably enhanced H2 evolution performance,and the H2 production rate is up to 13460.7μmol h^(-1)·g^(-1),which is up to around 29.0 and 4.7 times higher than those of Ti0_(2) nanosheets and Pt nanoparticles-Ti0_(2).In addition,a plausible enhanced reaction mechanism was also proposed combining with photo-electrochemical characterizations and density functional theoiy(DFT)calculation results.Ultimately,it is believed that this work highlights the benefits of a single-site catalyst and paves the way to rationally design the highly active and stable single-atomic site photocatalysts on metal oxide support.展开更多
文摘固体氧化物燃料电池钙钛矿阳极材料可以通过改性获得优异的催化活性,低的极化阻抗和稳定的抗积炭能力。在此,以立方相钙钛矿Pr_(0.4)Sr_(0.6)Co_(0.2)Fe_(0.7)Mo_(0.1)O_(3-δ)作为阳极前驱体,然后将CeO_(2)成功地浸渍到阳极的多孔结构中。通过原位还原技术获得了纳米合金粒子负载钙钛矿基底的复合阳极用于质子导体乙烷固体氧化物燃料电池。在氢气和乙烷气氛中,750℃时,燃料电池峰值功率密度分别达到253和183 m W·cm^(-2)。而且,在十小时的测试中燃料电池性能没有衰减反而电流密度随着时间的延长而增加,表明CeO_(2)浸渍表现出优异的催化活性和抗积炭稳定性。同时,通过产物分析,乙烯的产率从650℃下的23.52%增加到750℃下的34.09%,并且乙烯选择性超过94%。因此改性的阳极通过析出的纳米颗粒与CeO_(2)的协同作用,促进了燃料电池电极的催化活性和稳定性,将其运用到质子导体固体氧化物乙烷燃料电池中成功实现了乙烯与电能的共生。
基金This research was funded by the Canadian Centre for Clean Coal/Carbon and Mineral Processing Technologies(C5MPT),the National Key R&D Program of China(2017YFB0310803)and the China Scholarship Council(CSC).We thank the NanoFAB at the University of Alberta for the convenience of instruments use,and the kindly help of Nanqi Duan and Chao Qi on sample characterization.
文摘Single-atomic site catalysts have drawn considerable attention because of their maximum atom-utilization efficiency and excellent catalytic activity.In this work,a highly active single-atomic Pt site photocatalyst was synthesized through employing defective Ti0_(2) nanosheets as solid support for photo-catalytic water splitting.It indicated that the surface oxygen vacancies on defective Ti0_(2) nanosheets could effectively stabilize the single-atomic Pt sites through constructing a three-center Ti-Pt-Ti structure.The Ti-Pt-Ti structure can hold the stability of isolated single-atomic Pt sites and facilitate the separation and transfer of photoinduced charge carriers,thereby greatly improving the photocatalytic H2 evolution.Notably,our synthesized photocatalyst exhibited a remarkably enhanced H2 evolution performance,and the H2 production rate is up to 13460.7μmol h^(-1)·g^(-1),which is up to around 29.0 and 4.7 times higher than those of Ti0_(2) nanosheets and Pt nanoparticles-Ti0_(2).In addition,a plausible enhanced reaction mechanism was also proposed combining with photo-electrochemical characterizations and density functional theoiy(DFT)calculation results.Ultimately,it is believed that this work highlights the benefits of a single-site catalyst and paves the way to rationally design the highly active and stable single-atomic site photocatalysts on metal oxide support.
