V2O5@RuO2 core-shell heterojunction nano-arrays as electrode material for supercapacitors
V2O5@RuO2 core-shell heterojunction nano-arrays as electrode material for supercapacitors
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DOI：
10.1016/j.cej.2022.136922
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发表时间：
2022-05
影响因子：
15.1
通讯作者：
Jing Wang;F. Zheng;Mingjun Li;Jiao Wang;Donghua Jia;X. Mao;P. Hu;Q. Zhen;Yitong Yu
中科院分区：
文献类型：
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作者：
Jing Wang;F. Zheng;Mingjun Li;Jiao Wang;Donghua Jia;X. Mao;P. Hu;Q. Zhen;Yitong Yu
在多孔镍上直接合成V2 O 5纳米带阵列（VNB）作为初级结构，然后在VNB上完全覆盖RuO 2纳米片（RNS）作为次级结构，形成核壳异质结。采用SEM、EDS、XRD、XPS和TEM等手段对所制备的VNBs@ RNS核壳异质结进行了系统的研究，并通过不同时间取样，详细研究了VNBs@ RNS核壳异质结的生长过程。在5 mV s-1的电压扫描速度下，VNBs@ RNS的比容量高达971 F g-1，循环10,000次后的循环稳定性为80.4%，电荷转移电阻值为1.8 Ω，有效扩散系数CV，GCD计算为1.01 × 10 - 8 cm 2 s-1，三电极测试系统中的交流阻抗和CA电化学技术。由所制备的VNBs@ RNS电极材料组装的对称电化学电容器在双电极测试系统中在450 W kg− 1的功率密度下具有174.2 W h kg− 1的上级能量密度，并且在9000 W kg− 1下仍保持95.9 W h kg− 1。提高的超级电容性能使得VNB @ RNS成为超级电容器的上级电极材料。
V2O5nanobelt arrays (VNBs) are directly synthesized on porous nickel as the primary structure, and then the VNBs are completely covered by RuO2nanosheets (RNSs) as the secondary structure to create a core–shell heterojunction. The as-prepared VNBs@RNSs core–shell heterojunction is systematically researched through SEM, EDS, XRD, XPS and TEM, and the growth process is investigated in detail by sampling at different time. The VNBs@RNSs has a superb specific capacitive value of 971F g−1at a voltage scanning speed of 5 mV s−1, a better cyclic steadiness of 80.4 % after recycling 10,000 times, a small charge transferring resistance value of 1.8 Ω and a fast effective diffusion coefficient of 1.01 × 10−8cm2s−1calculated by CV, GCD, AC impedance and CA electrochemical techniques in a three-electrode testing system. A symmetrical electrochemical capacitor assembled by the as-prepared VNBs@RNSs electrode material has a superior energy density of 174.2 W h kg−1at a power density of 450 W kg−1and still retains 95.9 W h kg−1at 9000 W kg−1in a two-electrode testing system. The improved supercapacitive performance makes the VNBs@RNSs as a superior electrode material for supercapacitor.