Fig. 9.

a Energy profiles for Li atom diffusion on C₃N/GRA, along with the corresponding pathways denoted as red arrows. Carbon atoms from graphene—gray balls, carbon atoms from C₃N—orange balls, nitrogen atoms—blue and lithium atoms—green. Reproduced with permission from Ref. [37]. b Top and side views of Li₁₃–C₂N structure; c top and side views of the Li₁₁–C₂N/graphene bilayer. Different adsorption sites are indicated as CN1, CN2, CN3, GCN1, GCN2, and GCN3 for both structures. Reproduced with permission from Ref. [38]. d Top and side views of the Li adsorption site on the C₃N/P heterostructure (Li/C₃N/P, C₃N/Li/P, and C₃N/P/Li). HC and TN sites are on the outer surface of C₃N, and HP site is on the outer surface of phosphorene, HCP, HNP, BCP, and BNP sites are in the interlayer of the C₃N/P heterostructure. Reproduced with permission from Ref. [64]. e Lithium migration pathway and corresponding energy profile through Path II of the interlayer of C₃N/Blue P heterostructure. Reproduced with permission from Ref. [65]. f Adsorption energy for S₈ cluster and LiPSs on C₄N₄ monolayer (bars without patterns) and graphene (bars with patterns), respectively. The insets on the pillars show S₈ or Li₂Sn/C₄N₄ structures generated by the principle of minimum energy. Reproduced with permission from Ref. [56]. Copyright permissions from Elsevier, American Chemical Society and Royal Society of Chemistry. (Color figure online)