The biggest drawback of graphene is its resistance for ion adsorption, which results in a limited ability to store ions. There are methods described in the literature that can alter graphene's structure and impact its inert behavior. Typical of these methods are creating point and line defects, adding extra atoms, and substituting carbon atom with another one.

Recently, there has been studies to replace the carbon atoms  of graphene with germanium. The so called germagraphene is a two-dimensional material composed of germanium and carbon atoms arranged in a honeycomb lattice. Germagraphene has a higher theoretical capacity than the graphene due to the presence of germanium atoms, which can increase the number of lithium ions that can be stored in the material. It also has higher electronic conductivity than graphene due to the presence of germanium atoms, which can facilitate the transport of electrons during battery charging and discharging processes. The germanium atom creates an active site in the structure and therefore contributes to the improvement of battery performance by enhancing the electron transfer at the electrode-electrolyte interface. Overall, germagraphene's unique properties make it a promising material for battery applications, particularly as a cathode material in dual-carbon batteries (DCBs), which are low-cost and environmentally friendly alternatives to conventional lithium-ion batteries.

The reversible coupling of ions at two carbon-based electrodes forms the foundation of the energy storage technology known as DCBs. The lack of appropriate cathode materials, however, restricts the development of high-performance dual-carbon batteries. An intriguing cathode material for dual-carbon batteries has been reported by our group in a recent publication entitled “First-Principles Investigation of Charged Germagraphene as a Cathode Material for Dual-Carbon Batteries” [1]. Charged germagraphene was investigated as a potential cathode material using first-principles techniques to examine its electrochemical characteristics. First-principles calculations using density functional theory (DFT) were employed to evaluate the electronic properties of graphene and germagraphene for both under neutral and electrically biased conditions. The effective screening method (ESM) method was used to calculate these properties under electrical bias [2].

In this presentation, the atomistic picture of germagraphene as a cathode material that outperforms graphene in terms of electrochemical performance will be drawn. The enhanced anion adsorption on germagraphene is due to its reduced work function, higher charge carrier mobility, and redox potential. The research also showed that anions are easily adsorbed onto the surface of the charged germagraphene. The results demonstrate a significant potential of charged germagraphene as a positive electrode material for sustainable energy storage systems.