In situ growth of NiCo2S4 nanotube arrays on Ni foam for supercapacitors: Maximizing utilization efficiency at high mass loading to achieve ultrahigh areal pseudocapacitance

• Published in: Journal of power sources Vol. 254; pp. 249 - 257
• Main Authors: Chen, Haichao, Jiang, Jianjun, Zhang, Li, Xia, Dandan, Zhao, Yuandong, Guo, Danqing, Qi, Tong, Wan, Houzhao
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.05.2014; Elsevier
• Subjects: Applied sciences; Asymmetric; Capacitors. Resistors. Filters; Electrical engineering. Electrical power engineering; Exact sciences and technology; Nanotube arrays; Nickel cobalt sulfide; Supercapacitors; Various equipment and components; Supercapacitors; Asymmetric; Nanotube arrays; Nickel cobalt sulfide; Performance evaluation; Growth; Cobalt Sulfides; In situ; Nanotube; Transition metal; Electrolytic capacitor; Nickel Sulfides; Loading; Efficiency; Metal foam; Supercapacitor; Capacitance; Nickel; Cobalt sulfide
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2013.12.092

Self-standing NiCo2S4 nanotube arrays have been in situ grown on Ni foam by the anion-exchange reaction and directly used as the electrode for supercapacitors. The NiCo2S4 nanotube in the arrays effectively reduces the inactive material and increases the electroactive surface area because of the ultrathin wall, which is quite competent to achieve high utilization efficiency at high electroactive materials mass loading. The NiCo2S4 nanotube arrays hybrid electrode exhibits an ultrahigh specific capacitance of 14.39 F cm−2 at 5 mA cm−2 with excellent rate performance (67.7% retention for current increases 30 times) and cycling stability (92% retention after 5000 cycles) at a high mass loading of 6 mg cm−2. High areal capacitance (4.68 F cm−2 at 10 mA cm−2), high energy density (31.5 Wh kg−1 at 156.6 W kg−1) and high power density (2348.5 W kg−1 at 16.6 Wh kg−1) can be achieved by assembling asymmetric supercapacitor with reduced graphene oxide at a total active material mass loading as high as 49.5 mg. This work demonstrates that NiCo2S4 nanotube arrays structure is a superior electroactive material for high-performance supercapacitors even at a mass loading of potential application-specific scale. [Display omitted] •NiCo2S4 nanotube arrays have been synthesized based on the anion-exchange reaction.•The specific structure achieves high utilization efficiency of NiCo2S4 at high mass loading.•Ultrahigh specific capacitance with superior rate performance has been achieved.•The asymmetric supercapacitor cell has been assembled.•The cell delivers superior capacitive performance at high mass loading.