纳米多孔合金快速燃烧氧化及高效储能研究  

Rapid oxidation of nanoporous alloys by self-combustion and their high-efficiency energy storage performance

作　　者：王津 张少飞 孙金峰 李田田 WANG Jin;ZHANG Shaofei;SUN Jinfeng;LI Tiantian(School of Materials Science and Engineering,Hebei University of Science and Technology,Shijiazhuang 050018,Hebei,China)

机构地区：[1]河北科技大学材料科学与工程学院,河北石家庄050018

出　　处：《储能科学与技术》2023年第5期1480-1489,共10页Energy Storage Science and Technology

基　　金：国家自然科学基金(52101251);河北省教育厅青年拔尖人才(BJK2023058);河北省自然科学基金(E2020208069)。

摘　　要：具有高理论比容量的过渡金属氧化物在超级电容器储能领域受到高度重视,然而其高倍率、长循环应用仍存在挑战。本研究以三明治复合NiCuMn/Ni/NiCuMn为母合金,通过脱合金化和自燃烧相结合的工艺制备了一体化、高导电三元多孔NiCuMn体系过渡金属氧化物基电极(MPO-NiCuMn),探究了Cu掺杂量对储能的影响。研究发现,不同Cu掺杂量的母合金在Mn选择性脱出后,会在对称合金层形成三维双连通纳米多孔结构。由于该纳米多孔合金前驱体具有高比表面能,可在含氧空气条件下牺牲部分金属自发燃烧氧化,在保持高导电性的同时提高氧化物负载量(>8mg/cm^(2))。电化学性能表征发现,Cu掺杂量为15%时制备的MPO-Ni15Cu15Mn70电极可在50mA/cm^(2)的大电流密度下展现出12.2F/cm^(2)的比电容,远高于MPO-Ni20Cu10Mn70(5.6F/cm^(2))和MPO-Ni10Cu20Mn70(7.7F/cm^(2))电极。以相同面积的MPO-Ni15Cu15Mn70电极组装的对称超级电容器在50mA/cm^(2)电流密度下循环8000次后,容量保持率为95.7%,且倍率性能优异。该对称器件在功率密度为4.2mW/cm^(2)时,具有241mWh/cm^(2)的高能量密度。本研究验证了适量Cu的掺杂可起到主要协同作用,有效改善超级电容器的储能性能。Transition metal oxides(TMOs)with high theoretical specific capacitance have attracted considerable attention in the field of supercapacitors;however,their high-rate and long-term applications are still challenging.In this work,a series of ternary NiCuMn-based electrodes(MPO-NiCuMn)with high-electrical conductivity and porous structure was prepared by combining dealloying and self-combustion methods and using the sandwich-like NiCuMn/Ni/NiCuMn as the mother alloy.Then,the effect of Cu doping on the electrochemical properties was investigated.The results show that the Ni-supported nanoporous alloy layers were formed by the one-step dealloying process.Because of the high-specific surface energy of the NP-NiCuMn precursor,the alloy can self-combust in an open system by partial selfsacrifice.By this one-step combustion method,the final electrodes could simultaneously enhance the electrical conductivity and promote the mass loading of TMOs.The electrochemical performance shows that the MPO-Ni15Cu15Mn70 electrode with 15%Cu dopant has a maximum areal capacitance of 12.2 F/cm^(2) at a high current density of 50 mA/cm^(2),much higher than that of MPO-Ni20Cu10Mn70(5.6 F/cm^(2))and MPO-Ni10Cu20Mn70(7.7 F/cm^(2))electrodes.The assembled symmetric supercapacitor demonstrates outstanding cyclic stability with a capacitance retention of 95.7%after 8000 cycles at a current density of 50 mA/cm^(2),as well as a high-rate performance.It also shows a high energy density of 241 mWh/cm^(2) at a power density of 4.2 mW/cm^(2).This study verified that doping using appropriate amounts of Cu can play a major synergistic role in effectively improving the energy storage performance of supercapacitors.

关 键 词：脱合金 自燃烧氧化 过渡金属氧化物 电化学性能 

分 类 号：TB[一般工业技术]