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Exploring more high-performance anode materials for sodium-ion batteries (SIBs) can smoothly help to build a more sustainable, cleaner, and reliable energy system. This study systematically investigates the potential of 2D pristine SiCN (p-SiCN) and defective (d-SiCN) substrate as candidate materials for SIBs anodes using first-principles computational method. The computational results reveal that the p-SiCN possesses excellent thermal stability and structural cyclical performance, good conductivity, high theoretical specific capacity (1486 mAh·g−1), low diffusion barrier (0.177 eV), and appropriate open-circuit voltage (0.340 V), which allows the p-SiCN substrate more suitable as a potential anode material for SIBs. Furthermore, by investigating the effects of intentionally designed defects on p-SiCN, it is observed that the adsorption energy and diffusion barrier of the Na atom on the d-SiCN substrate increase. Our work demonstrates that investigating the effect of defects on p-SiCN can better explore the properties of anode materials, thus further optimizing the battery performances.

For the widespread commercialization of lithium‑sulfur (LiS) batteries, the identification of anchoring materials capable of effectively mitigating the shuttle effect is of paramount importance. This study is centered around examining the adsorption characteristics of lithium polysulfides (S8and Li2Sn, n = 1, 2, 4, 6, 8), as well as investigating the sulfur reduction reaction (SRR), and the decomposition mechanisms of Li2S on the pristine and defective Hd-Graphene monolayers. These investigations were carried out using first-principles calculations. The results reveal that the adsorption energies of polysulfides to the electrolytes (DOL and DME) are lower compared to that on the substrates. The moderate anchoring strength (0.8–2.0 eV) between polysulfides and the monolayer can effectively suppress the shuttle effect. Additionally, the Gibbs free energy barrier for SRR on the substrate is determined to be about 0.68 eV. The dissociation energy barrier of Li2S on Hd-Graphene is about 1.54 eV. Lower energy barriers indicate favorable reaction kinetics, leading to improved discharging and charging efficiency. Based on these findings, Hd-Graphene is predicted to be a promising anchoring material for LiS batteries.