CdS Nanoparticles Decorated on Carbon Nanofibers as the First Ever Utilized as an Electrode for Advanced Energy Storage Applications

Electrode material with exceptional durability, energy density, and rate performance has been of great interest in next-generation advanced supercapacitor applications in recent years. In this paper, we portray the facile synthesis of carbon nanofibers (CNFs) and cadmium sulfide (CdS) for a supercapacitor that obtained the capacitances of 335 F/g and 210 F/g when tested in an aqueous conducting medium in a three-electrode mode over a wide potential range between 0.0 to 0.8 V. The performance of pure electrode materials is not satisfactory; therefore, a composite of CdS/CNFs was further fabricated that exhibits enhanced energy storage performance in terms of the capacitance of 510 F/g, and a minor charge transfer resistance compared with pure counterparts. The fascinating performance was turned to develop an asymmetric supercapacitor (CdS/CNFs||AC), which realizes a high voltage of up to 2.0 V. It is believed that optimization of voltage put significant enhancement in energy and power delivery. Interestingly, a high power of 9000 W/kg was accomplished with maximum energy of 31.94 Wh/kg at high and low discharge current rates. Additionally, only a 15.3% capacity fade was attained and 85.7% retention at a high current rate of 20 A/g for 7500 cycles. Our strategy is synthesizing other metal oxide-based composite electrodes for future energy storage domains.

Automated summary

Electrode materials with exceptional durability, energy density, and rate performance are highly sought after for next-generation advanced supercapacitors. This paper presents a facile synthesis technique for carbon nanofibers (CNFs) and cadmium sulfide (CdS) for a supercapacitor, achieving capacitances of 335 F/g and 210 F/g when tested in an aqueous conducting medium in a three-electrode mode. By further fabricating a composite of CdS/CNFs, enhanced energy storage performance and reduced charge transfer resistance were observed. An asymmetric supercapacitor (CdS/CNFs||AC) was developed, achieving a high voltage of up to 2.0 V. Notably, a high power of 9000 W/kg and maximum energy of 31.94 Wh/kg at high and low discharge currents were achieved. The capacity fade was only 15.3% and 85.7% retention at a high current rate of 20 A/g for 7500 cycles. The strategy of synthesizing other metal oxide-based composite electrodes for future energy storage domains is also discussed.