It is widely recognized that the development of ZABs is impeded by the kinetic bottleneck of oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).The application of conformational entropy strategy to oxide...It is widely recognized that the development of ZABs is impeded by the kinetic bottleneck of oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).The application of conformational entropy strategy to oxides often involves introducing multiple elements with different properties,thereby providing outstanding bifunctional catalytic activity for OER/ORR.Nevertheless,the possible underlying catalytic pathways and potential interactions between various components are still poorly understood.This paper presents an excellent medium-entropy perovskite oxide,Sr(FeCoNiMo)_(1/4)O_(3−δ)(lower overpotential of 301 mV at 10 mA cm^(−2)).Zinc-air batteries employing it as a cathode catalyst demonstrate excellent round-trip efficiency(62%).By combining theoretical calculation with experiments,we aim to establish the link between the electronic structure of perovskite oxides with different elemental compositions and their OER mechanism.Research reveals that the conformational entropy strategy can simultaneously shift the O 2p-band center and metal d-band center of perovskite oxide towards the vicinity of the Fermi energy level,thereby triggering a more favorable lattice oxygen-participated mechanism(LOM)during the OER process.The outcomes of this work provide crucial insights into the role of conformational entropy strategies in oxygen catalysis and offer potential avenues for constructing efficient and stable electrocatalysts.展开更多
Highly active solid superacid catalysts for n-butane isomerization, SZ/A1_2O_3-P, were prepared by supporting SO-(4-2)/ZrO2, (SZ) on y-A1_2O_3 carrier using a precipitation method. The activities of some catalysts wer...Highly active solid superacid catalysts for n-butane isomerization, SZ/A1_2O_3-P, were prepared by supporting SO-(4-2)/ZrO2, (SZ) on y-A1_2O_3 carrier using a precipitation method. The activities of some catalysts were enhanced significantly j The activity of the most active sample. 60%SZ/Al_2O3-P, was even about 2 times more active than that of the SZ catalyst.展开更多
NASICON型快离子导体Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)(LATP)具有较高的离子电导率、较宽的电化学窗口及良好的水和空气稳定性,但其界面接触性能差。石榴石型Li_(7)La_(3)Zr_(2)O_(12)(LLZO)锂离子电导率高、电化学窗口较宽且热稳定...NASICON型快离子导体Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)(LATP)具有较高的离子电导率、较宽的电化学窗口及良好的水和空气稳定性,但其界面接触性能差。石榴石型Li_(7)La_(3)Zr_(2)O_(12)(LLZO)锂离子电导率高、电化学窗口较宽且热稳定性好,但其立方相结构不稳定,影响其实际应用。采用溶液浇筑法,制备纯PVDF-LiTFSI电解质膜和以PVDF为基、3种不同质量比的Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)和Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)的固态电解质膜,并探讨纯PVDF-LiTFSI电解质膜和3种不同质量比的活性无机电解质填料对复合固态电解质离子电导率的影响。结果表明,Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)和Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)质量比为1∶1时,电解质膜的XRD图谱的衍射峰比纯PVDF-LiTFSI下降更为明显,电化学窗口为3.9 V左右,表现出更好的稳定性。在不同温度下分别测量其离子电导率发现,Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)和Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)质量比为1∶1时的电解质膜均高于纯PVDF-LiTFSI电解质膜和Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)和Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)质量比为2∶1和3∶1时的电解质膜。将其装配成电池后发现,0.1C下电池首次充放电比容量分别为90 m A·h/g和87 m A·h/g。以0.5C的电流循环25圈,放电比容量从57 mA·h/g衰减至51mA·h/g,容量保持率为99.7%。所以,以PVDF为基、Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)和Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)质量比为1∶1的固态电解质膜有优良的倍率性能和循环稳定性能。展开更多
基金the financial support from the National Natural Science Foundation of China (51872067 and 21773048)
文摘It is widely recognized that the development of ZABs is impeded by the kinetic bottleneck of oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).The application of conformational entropy strategy to oxides often involves introducing multiple elements with different properties,thereby providing outstanding bifunctional catalytic activity for OER/ORR.Nevertheless,the possible underlying catalytic pathways and potential interactions between various components are still poorly understood.This paper presents an excellent medium-entropy perovskite oxide,Sr(FeCoNiMo)_(1/4)O_(3−δ)(lower overpotential of 301 mV at 10 mA cm^(−2)).Zinc-air batteries employing it as a cathode catalyst demonstrate excellent round-trip efficiency(62%).By combining theoretical calculation with experiments,we aim to establish the link between the electronic structure of perovskite oxides with different elemental compositions and their OER mechanism.Research reveals that the conformational entropy strategy can simultaneously shift the O 2p-band center and metal d-band center of perovskite oxide towards the vicinity of the Fermi energy level,thereby triggering a more favorable lattice oxygen-participated mechanism(LOM)during the OER process.The outcomes of this work provide crucial insights into the role of conformational entropy strategies in oxygen catalysis and offer potential avenues for constructing efficient and stable electrocatalysts.
文摘Highly active solid superacid catalysts for n-butane isomerization, SZ/A1_2O_3-P, were prepared by supporting SO-(4-2)/ZrO2, (SZ) on y-A1_2O_3 carrier using a precipitation method. The activities of some catalysts were enhanced significantly j The activity of the most active sample. 60%SZ/Al_2O3-P, was even about 2 times more active than that of the SZ catalyst.
文摘NASICON型快离子导体Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)(LATP)具有较高的离子电导率、较宽的电化学窗口及良好的水和空气稳定性,但其界面接触性能差。石榴石型Li_(7)La_(3)Zr_(2)O_(12)(LLZO)锂离子电导率高、电化学窗口较宽且热稳定性好,但其立方相结构不稳定,影响其实际应用。采用溶液浇筑法,制备纯PVDF-LiTFSI电解质膜和以PVDF为基、3种不同质量比的Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)和Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)的固态电解质膜,并探讨纯PVDF-LiTFSI电解质膜和3种不同质量比的活性无机电解质填料对复合固态电解质离子电导率的影响。结果表明,Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)和Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)质量比为1∶1时,电解质膜的XRD图谱的衍射峰比纯PVDF-LiTFSI下降更为明显,电化学窗口为3.9 V左右,表现出更好的稳定性。在不同温度下分别测量其离子电导率发现,Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)和Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)质量比为1∶1时的电解质膜均高于纯PVDF-LiTFSI电解质膜和Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)和Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)质量比为2∶1和3∶1时的电解质膜。将其装配成电池后发现,0.1C下电池首次充放电比容量分别为90 m A·h/g和87 m A·h/g。以0.5C的电流循环25圈,放电比容量从57 mA·h/g衰减至51mA·h/g,容量保持率为99.7%。所以,以PVDF为基、Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)和Li_(1+x)Al_(x)Ti_(2-x)(PO_(4))_(3)质量比为1∶1的固态电解质膜有优良的倍率性能和循环稳定性能。
