皱褶表面介孔镍钴硫化物微球的制备及其超电性能

发布时间：2019-02-09 19:42

【摘要】：通过一步水热法分别合成了α-Ni S、Co_3S_4和Co Ni_2S_4纳米介孔电极材料,并研究了其电化学性能。X射线衍射(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)研究表明,介孔硫化物是由单相纳米颗粒堆叠组装而成,其中二元系的Co Ni_2S_4由纳米片自组装形成了具有皱褶表面的微球形貌。电化学性能研究表明,二元系的Co Ni_2S_4比α-Ni S、C o_3S_4具有更高的比电容、更佳的倍率特性和优异的循环稳定性。在扫描速率为5 m V/s时,Co Ni_2S_4材料在6 mol/L KOH电解液中比电容高达1678.3 F/g,优于α-Ni S(787.4 F/g)和Co_3S_4(1532.7 F/g),在扫描速率从5 m V/s增加到100 m V/s时,其电容保持率为45.8%,比α-Ni S(30.2%)和Co_3S_4(29.3%)高出约15%。在15A/g的电流密度下,经过900次循环充-放电后,二元系的Co Ni_2S_4的电容仍保持在96.3%,库伦效率保持在94.3%左右,说明镍钴双金属硫化物具有优异的循环稳定性能和充放电可逆性。
[Abstract]:伪-Ni Sesco _ 3S _ 3s _ 4 and Co Ni_2S_4 mesoporous electrode materials were synthesized by one-step hydrothermal method, and their electrochemical properties were studied. X-ray diffraction (XRD),) Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies show that mesoporous sulfides are assembled by stacking single-phase nanoparticles. Among them, the Co Ni_2S_4 of binary system was self-assembled from the nanochip to form the morphology of the microspheres with wrinkled surface. The electrochemical properties of the binary system show that Co Ni_2S_4 has higher specific capacitance, better rate characteristics and better cycle stability than 伪-Ni o_3S_4. At a scanning rate of 5 MV / s, the specific capacitance of Co Ni_2S_4 in 6 mol/L KOH electrolytes is as high as 1678.3 F / g, which is superior to 伪-Ni S (787.4 F / g and Co_3S_4 (1532.7 F / g). When the scanning rate is increased from 5 MV / s to 100m V / s, the capacitance retention is 45.8%, which is about 15% higher than 伪-Ni S (30.2% and Co_3S_4 (29.3%). At the current density of 15A/g, after 900 cycles of charge-discharge, the capacitance of Co Ni_2S_4 in binary system remains at 96.3and the Coulomb efficiency is about 94.3%. It shows that nickel cobalt bimetallic sulfides have excellent cyclic stability and charge / discharge reversibility.
【作者单位】：宁夏大学化学化工学院能源化工重点实验室;
【基金】：国家自然科学基金资助项目(21361020,21561026)~~
【分类号】：O611.4;TM53

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