Reversible intercalation and exfoliation of layered covalent triazine frameworks for enhanced lithium ion storage

We report that layered covalent triazine frameworks (CTF-1) can be rapidly and reversibly intercalated with either an oxidizing or a non-oxidizing acid based on the acid-base driven mechanism. The obtained CTF-1 intercalated compounds can be readily reacted with nitronium ions and spontaneously exfoliated into 1-2 layered functionalized CTF-1 nanosheets ( f -CTF-1) with a high yield of 42%. The f -CTF-1 shows a 2.5 to 3.8 times increase in specific capacitance and much better rate performance when used as an LIB anode. Layered covalent triazine frameworks can be exfoliated into 1-2 layered nanosheets via acid-base intercalation and subsequent oxidation exfoliation to obtain much improved specific capacitance and rate performance for Li ion battery anode.