多硫化物的穿梭效应是锂硫(Li-S)电池最致命的固有问题。本文通过在商业聚丙烯隔膜上涂覆碳纳米管支撑的MoSe2纳米片,成功构建了对多硫化物具有强吸附作用的功能化夹层,有效抑制了多硫化物穿梭效应的发生。将该功能化隔膜用于锂硫电池,...多硫化物的穿梭效应是锂硫(Li-S)电池最致命的固有问题。本文通过在商业聚丙烯隔膜上涂覆碳纳米管支撑的MoSe2纳米片,成功构建了对多硫化物具有强吸附作用的功能化夹层,有效抑制了多硫化物穿梭效应的发生。将该功能化隔膜用于锂硫电池,可获得良好的储能性质。在电流密度为0.1C时,电池的初始比容量高达1485 mAh g^−1。在高电流密度(2C)下,电池的比容量仍能达到880 mAh g^−1,说明电池的倍率性能较好。此外,电池在电流密度为0.5 C时表现出优异的长期循环稳定性。在循环300次的过程中,电池每圈容量的衰减率仅为0.093%。这些优异的储能特性得益于MoSe2对多硫化物的强吸附作用以及CNTs良好的导电性。展开更多
严重的穿梭效应和缓慢的氧化还原动力学导致锂硫电池出现容量衰减快,倍率性能差等问题。为此,以Ti_(3)C_(2)T_(x)为活性材料、碳纳米管为导电骨架合成出可吸附和催化转化多硫化锂的三维CNT/Ti_(3)C_(2)T_(x)气凝胶。其独特的三维多孔结...严重的穿梭效应和缓慢的氧化还原动力学导致锂硫电池出现容量衰减快,倍率性能差等问题。为此,以Ti_(3)C_(2)T_(x)为活性材料、碳纳米管为导电骨架合成出可吸附和催化转化多硫化锂的三维CNT/Ti_(3)C_(2)T_(x)气凝胶。其独特的三维多孔结构,一方面有效地避免了二维Ti_(3)C_(2)T_(x)纳米片的重堆叠问题,使更多的活性位点暴露出来,增强对多硫化锂的吸附和催化转化;另一方面提供了大量的电荷传输路径。而且,气凝胶中的碳纳米管既提供了高性能的导电网络,又通过在Ti_(3)C_(2)T_(x)纳米片之间建立有效连接增强了材料的韧性。将CNT/Ti_(3)C_(2)T_(x)气凝胶用于修饰锂硫电池隔膜,获得了在电流密度为2 C时电池容量为1043.2 mAh g^(−1);在电流密度为0.5 C时循环800圈,每圈容量衰减率仅为0.07%的良好性能。展开更多
One-dimension InAlO3 (ZnO)m superlattice nanowires were successfully synthesized via chemical vapor deposition. Transmission electron microscopy measurements reveal that the nanowires have a periodic layered structu...One-dimension InAlO3 (ZnO)m superlattice nanowires were successfully synthesized via chemical vapor deposition. Transmission electron microscopy measurements reveal that the nanowires have a periodic layered structure along the (0001) direction. The photoluminescence properties of InAlO3(ZnO)m superlattice nanowires are studied for the first time. The near-band-edge emissions exhibit an obvious red shift due to the formation of the localized tail states. The two peaks centered at 3.348 eV and 3.299 eV indicate a lever phenomenon at the low-temperature region. A new luminescence mechanism is proposed, combined with the special energy band structure of InAlO3(ZnO)m.展开更多
One-dimensional(ID) In2O3(ZnO)m superlattice nanobelts are synthesized by a chemical vapor deposition method.The formation of the In2O3(ZnO)m superlattice is verified by the high-resolution transmission electron...One-dimensional(ID) In2O3(ZnO)m superlattice nanobelts are synthesized by a chemical vapor deposition method.The formation of the In2O3(ZnO)m superlattice is verified by the high-resolution transmission electron microscopy images.The typical zigzag boundaries could be clearly observed.An additional peak at 614 cm^-1 is found in the Raman spectrum,which may correspond to the superlattice structure.The study about the electrical transport properties reveals that the In2O3(ZnO)m nanobelts exhibit peculiar nonlinear I-V characteristics even under the Ohmic contact measurement condition,which are different from the Ohmic behaviors of the In-doped ZnO nanobelts.The photoelectrical measurements show the differences in the photocurrent property between them,and their transport mechanisms are also discussed.展开更多
采用一步机械合金化的方法合成了高纯度Ti_3AlC_2.以此高纯度Ti_3AlC_2为前驱体,采用简单安全的方法进行腐蚀剥离,成功地制备出具有良好柔韧性的Ti_3C_2T_x薄膜电极.在1 M KOH电解液中进行电化学测试,扫速为2 mV/s时,Ti_3C_2T_x的体电...采用一步机械合金化的方法合成了高纯度Ti_3AlC_2.以此高纯度Ti_3AlC_2为前驱体,采用简单安全的方法进行腐蚀剥离,成功地制备出具有良好柔韧性的Ti_3C_2T_x薄膜电极.在1 M KOH电解液中进行电化学测试,扫速为2 mV/s时,Ti_3C_2T_x的体电容可达到509.7 F/cm^3,10000圈充放电循环后,电容保持率高达95%.因此,一步机械合金化方法合成的Ti_3AlC_2适用于Ti_3C_2T_x薄膜的制备,且得到的Ti_3C_2T_x薄膜具有很好的电容性质,可用于超级电容器电极材料.展开更多
文摘多硫化物的穿梭效应是锂硫(Li-S)电池最致命的固有问题。本文通过在商业聚丙烯隔膜上涂覆碳纳米管支撑的MoSe2纳米片,成功构建了对多硫化物具有强吸附作用的功能化夹层,有效抑制了多硫化物穿梭效应的发生。将该功能化隔膜用于锂硫电池,可获得良好的储能性质。在电流密度为0.1C时,电池的初始比容量高达1485 mAh g^−1。在高电流密度(2C)下,电池的比容量仍能达到880 mAh g^−1,说明电池的倍率性能较好。此外,电池在电流密度为0.5 C时表现出优异的长期循环稳定性。在循环300次的过程中,电池每圈容量的衰减率仅为0.093%。这些优异的储能特性得益于MoSe2对多硫化物的强吸附作用以及CNTs良好的导电性。
文摘严重的穿梭效应和缓慢的氧化还原动力学导致锂硫电池出现容量衰减快,倍率性能差等问题。为此,以Ti_(3)C_(2)T_(x)为活性材料、碳纳米管为导电骨架合成出可吸附和催化转化多硫化锂的三维CNT/Ti_(3)C_(2)T_(x)气凝胶。其独特的三维多孔结构,一方面有效地避免了二维Ti_(3)C_(2)T_(x)纳米片的重堆叠问题,使更多的活性位点暴露出来,增强对多硫化锂的吸附和催化转化;另一方面提供了大量的电荷传输路径。而且,气凝胶中的碳纳米管既提供了高性能的导电网络,又通过在Ti_(3)C_(2)T_(x)纳米片之间建立有效连接增强了材料的韧性。将CNT/Ti_(3)C_(2)T_(x)气凝胶用于修饰锂硫电池隔膜,获得了在电流密度为2 C时电池容量为1043.2 mAh g^(−1);在电流密度为0.5 C时循环800圈,每圈容量衰减率仅为0.07%的良好性能。
基金Project supported by the Science Foundation for Distinguished Young Scholars of Heilongjiang Province,China (Grant No.JC200805)the Natural Science Foundation of Heilongjiang Province of China (Grant Nos.A2007-03,A200807,and F200828)the Personnel Bureau Project of Overseas Talent of Heilongjiang Province,China
文摘One-dimension InAlO3 (ZnO)m superlattice nanowires were successfully synthesized via chemical vapor deposition. Transmission electron microscopy measurements reveal that the nanowires have a periodic layered structure along the (0001) direction. The photoluminescence properties of InAlO3(ZnO)m superlattice nanowires are studied for the first time. The near-band-edge emissions exhibit an obvious red shift due to the formation of the localized tail states. The two peaks centered at 3.348 eV and 3.299 eV indicate a lever phenomenon at the low-temperature region. A new luminescence mechanism is proposed, combined with the special energy band structure of InAlO3(ZnO)m.
基金supported by the National Natural Science Foundation of China(Grant No.51172058)the Key Project of the Science Technology and Research Project of Education Bureau,Heilongjiang Province,China(Grant No.12521z012)the Natural Science Foundation of Heilongjiang Province for Returned Chinese Scholars,China(Grant No.LC2013C17)
文摘One-dimensional(ID) In2O3(ZnO)m superlattice nanobelts are synthesized by a chemical vapor deposition method.The formation of the In2O3(ZnO)m superlattice is verified by the high-resolution transmission electron microscopy images.The typical zigzag boundaries could be clearly observed.An additional peak at 614 cm^-1 is found in the Raman spectrum,which may correspond to the superlattice structure.The study about the electrical transport properties reveals that the In2O3(ZnO)m nanobelts exhibit peculiar nonlinear I-V characteristics even under the Ohmic contact measurement condition,which are different from the Ohmic behaviors of the In-doped ZnO nanobelts.The photoelectrical measurements show the differences in the photocurrent property between them,and their transport mechanisms are also discussed.
文摘采用一步机械合金化的方法合成了高纯度Ti_3AlC_2.以此高纯度Ti_3AlC_2为前驱体,采用简单安全的方法进行腐蚀剥离,成功地制备出具有良好柔韧性的Ti_3C_2T_x薄膜电极.在1 M KOH电解液中进行电化学测试,扫速为2 mV/s时,Ti_3C_2T_x的体电容可达到509.7 F/cm^3,10000圈充放电循环后,电容保持率高达95%.因此,一步机械合金化方法合成的Ti_3AlC_2适用于Ti_3C_2T_x薄膜的制备,且得到的Ti_3C_2T_x薄膜具有很好的电容性质,可用于超级电容器电极材料.