Two-dimensional penta-siligraphene with high performance for non-lithium metal ions batteries anode materials

Non-lithium metal ion batteries (NLMIBs) will play an important part in sustainable energy and grid storage. Searching for high-performance electrode materials are critical to the development of NLMIBs. From first-principles calculations, we predict that penta-siligraphene (P-Si2C4), a new two-dimensional (2D) layered material obtained by replacing the sp(3) C atoms in penta-graphene with Si atoms, can be used as a promising anode material for NLMIBs including Na-, K-, Rb-, Ca-, Sr- and Ba-ion. The theoretical specific capacities for Na, Sr, Ba, Rb, K and Ca ions are 514.3, 1028.7, 1028.7, 578.6, 1028.7 and 2057.3 mA h g(-1), respectively. The metal-ion intercalation potentials (0.1-1.0 V) are suitable for battery application. After metal-ions adsorbed, the electronic structures of P-Si2C4 become metallic indicating of good electronic conductivity of the anode. The metal-ion/vacancy diffusion energy barriers on the surface of P-Si2C4 are relatively small and ensure good rate performance. Our research offers a promising high performance anode material for the application in NLMIBs.

Automated summary

Non-lithium metal ion batteries (NLMIBs) require high-performance electrode materials for their development. In this study, penta-siligraphene (P-Si2C4), a new two-dimensional material, is predicted to be a promising anode material for NLMIBs, with good specific capacities and suitable intercalation potentials for various metal ions. P-Si2C4 also exhibits metallic electronic structures, indicating excellent electronic conductivity, and has small diffusion energy barriers, ensuring good rate performance.