Rational Design of Porous Nanowall Arrays of Ultrafine Co4N Nanoparticles Confined in a La2O2CN2 Matrix on Carbon Cloth for a High-Performing Supercapacitor Electrode.
Rational Design of Porous Nanowall Arrays of Ultrafine Co4N Nanoparticles Confined in a La2O2CN2 Matrix on Carbon Cloth for a High-Performing Supercapacitor Electrode.
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DOI：
10.1021/acsami.2c09377
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发表时间：
2022-10
影响因子：
9.5
通讯作者：
Bo Cao;Baocang Liu;Zi-ming Xi;Yan Cheng;Xuang-Long Xu;P. Jing;R. Cheng;S. Feng;Jun Zhang-Jun-Zh
中科院分区：
文献类型：
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作者：
Bo Cao;Baocang Liu;Zi-ming Xi;Yan Cheng;Xuang-Long Xu;P. Jing;R. Cheng;S. Feng;Jun Zhang-Jun-Zh
过渡金属氮化物（TMN）由于其高导电性、良好的机械强度和优良的耐上级腐蚀性而作为重要的储能材料受到特别关注。然而，它们的容量不足和循环稳定性差限制了它们作为超级电容器的实际应用。在这里，一种新型的三维（3D）自支撑集成电极由多孔的超细氮化钴（Co 4 N）纳米粒子的阵列封装在碳布（Co4N@CON/CC）的氧氰氨化镧（CO4N@CON/CC）矩阵出色的电化学能量存储的合理设计和制造。多孔硅阵列的3D单片结构有利于质量/电荷转移、电活性位点的暴露和电导率的增强。同时，Co4N@SiO2独特的核壳结构可以防止超细Co 4 N纳米粒子的烧结、团聚和氧化，促进氧化还原反应过程中的电子转移动力学，同时提高电极的稳定性。此外，Co 4 N和Co2 O3的协同作用可以导致在充放电过程中的有效的电子/离子传输。由于这些特征，Co4N@SiO2/CC电极显示出上级的比电容（在1 mA cm-2下为895.6mF cm-2或613.4F g-1）和令人钦佩的循环耐久性（10000次循环后87.9%的电容保留），超过了迄今为止报道的大多数氮化物基电极。此外，在使用活性炭（AC）作为阳极组装成非对称超级电容器后，所获得的Co4N@CO2/CC//AC/CC装置在875.8W kg-1的功率密度下显示出41.7Wh kg-1的高能量密度，在2 mA cm-2下5000次循环后具有87.6%的高电容保留。本工作提供了一种将TMN与稀土化合物结合以提高超级电容器电极的TMN的电容和稳定性的有效方法。
Transition metal nitrides (TMNs) have received special concern as important energy storage materials, owing to their high conductibility, good mechanical strength, and superior corrosion resistance. However, their insufficient capacitance and poor cycling stability limit their practical applications for supercapacitors. Here, a novel three-dimensional (3D) self-supported integrated electrode consisted of porous nanowall arrays of ultrafine cobalt nitride (Co4N) nanoparticles encapsulated in a lanthanum oxycyanamide (LOC) matrix on carbon cloth (Co4N@LOC/CC) for outstanding electrochemical energy storage is rationally designed and fabricated. The 3D monolithic configuration of porous nanowall arrays facilitates the mass/charge transfer, the exposure of electroactive sites, and the enhancement of electrical conductivity. Meanwhile, the unique core-shell structure of Co4N@LOC can prevent ultrafine Co4N nanoparticles from sintering, agglomeration, and oxidation and promotes electron transfer dynamics during the redox reaction, meanwhile enhancing the stability of the electrode. Additionally, the synergy of Co4N and LOC can result in an efficient electron/ion transport in the process of the charge-discharge. Because of these features, the Co4N@LOC/CC electrode displays superior specific capacitance (895.6 mF cm-2 or 613.4 F g-1 at 1 mA cm-2) and admirable cycling durability (87.9% capacitance reservation after 10 000 cycles), surpassing the majority of nitride-based electrodes reported thus far. Furthermore, after being assembled into an asymmetric supercapacitor using active carbon (AC) as an anode, the obtained Co4N@LOC/CC//AC/CC device displays a high energy density of 41.7 Wh kg-1 at the power density of 875.8 W kg-1 with a high capacitance reservation of 87.6% after 5000 cycles at 2 mA cm-2. This work offers an efficient approach of combining TMNs with rare earth compounds to enhance the capacitance and stability of TMNs for supercapacitor electrodes.