A Brief Review on Heteroatom-Doped Dual-Carbon Metal-Ion Hybrid Capacitors: The Role of Carbon Nanomaterials

Numerous carbon nanomaterials, due to their affordability, safety, and tunability, are being widely investigated for energy storage applications. Dual carbon energy storage devices, from supercapacitors to batteries, are promising devices trending in recent years. This review focuses on the role of carbon nanomaterials in heteroatom-doped dual-carbon metal-ion hybrid capacitors (DC-MIC) from lithium to potassium and multivalent ions. DC-MIC is the combination of a carbon anode with a battery-like characteristic and a carbon cathode with capacitor-like characteristics, assembled in a single cell with a nonaqueous electrolyte. The research growth and issues surrounding dual carbon devices, the impact of heteroatom doping, their charge-storage mechanism, and electrode characteristics are introduced in the first section of this review. The next part deals with the reported doped carbon nanomaterials for DC-MIC from lithium to potassium and multivalent ion hybrid devices. Finally, projections for future investigations and insights are provided for doped DC-MIC devices.