Self-Activated NiCoAl-LDH@GO/GONRs electrode exhibits over 800% capacitance gain during Long-Term cycling
摘要
In this research, one step low-temperature hydrothermal process was used to fabricate nanohybrid electrodes based on ternary layered double hydroxide (LDH) compounds of NiCoAl-LDH type, incorporated within a three-dimensional conductive nanonetwork composed of graphene oxide (GO) and graphene oxide nanoribbons (GONRs). Additionally, a quaternary iron-containing composite (NiCoAlFe-LDH) was also prepared to investigate the effect of embedded Fe3+ on the electrochemical behavior of the composite. The prepared materials were characterized morphologically and their electrochemical performance was evaluated using the standard three-electrode configuration. The results showed that the quaternary compound possesses relatively higher performance due to the structural stability provided by the presence of iron. However, the difference between it and the ternary compound was not significant. On the contrary, the ternary compound exhibited a distinctive behavior represented by the self-activation phenomenon during prolong cycling, recording a gradual and clear increase in specific capacity (835% of its initial value) over time. The ternary LDH composite achieved high specific capacitance of 2330 Fg⁻¹ at a current density of 1 A·g⁻¹, Energy density of 646 Wh/kg at 700 W/kg and the Coulombic efficiency exceeding 99% with 8000 charge-discharge cycles. These results confirm that the ternary compound, prepared in a simple and economical manner, in addition to its self-activation property, represents a suitable option for high-performance energy storage systems.