Recent Advancements in Energy Storage Based on Sodium Ion and Zinc Ion Hybrid Supercapacitors

The hybrid supercapacitor is appealing for commercial applications which have the aptitude to supply high energy density without compromising other supercapacitor properties. The Review is the complete insight of a reported Na+- and Zn+-based hybrid supercapacitor with the principle of the working mechanism. The combination of different semiconductor-based electrodes as the anode or cathode has been presented so researchers can update the progress of the sodium-ion-based hybrid supercapacitor (Na-HSC). In pursuit of replacing the activated carbon (AC)-based electrode due to its limited capacitance which results from an imbalance between the cathode and anode, we provide this Review with tables, figures, and their comparative studies. Society is moving toward smart electronic and hybrid devices that require flexibility, resilience, and high safety as people closely interact with these devices. The zinc ion hybrid supercapacitor (Zn-HSCs) is a comprehensive solution to toxic and explosive sodium-ion and lithium-ion devices. This Review represents recent reported metal oxides, chalcogenides, ceramics, MXenes, and carbon-based materials used for Zn-HSCs. Additionally, the hybrid capacitors with flexibility and the lightweight micro-supercapacitors have been studied and presented along with their challenges for pragmatic usage.