Triazole‐Triazine‐Tetrazine Co‐Constructed Nitrogen‐Rich Covalent Organic Frameworks With Tunable H ₂ O ₂ Photosynthesis and Energetic Performance by Stepwise Oxidation Strategy

ABSTRACT Nitrogen‐rich covalent organic frameworks (COFs) show strong potential in catalysis, sensing, and energetic materials, however achieving both ultrahigh nitrogen content and high crystallinity remains challenging. Here, we develop a stepwise oxidation strategy to obtain three triazole‐triazine‐tetrazine co‐constructed COFs (TTTsT‐H, TTTsT, and TTTsT‐O): First, a highly crystalline COF TTTsT‐H with an ultrahigh nitrogen content was obtained under optimized experimental conditions; Subsequently, TTTsT and its N‐oxide derivative TTTsT‐O were synthesized using a stepwise oxidation strategy. The results demonstrate that these frameworks possess significant potential for photocatalysis and energetic materials. Notably, TTTsT is an efficient photocatalyst for H 2 O 2 (hydrogen peroxide) production, achieving a yield of 2798.4 µmol g −1 h −1 . The theoretically predicted detonation performance of TTTsT‐O is comparable to that of currently used high explosives RDX (Hexogen) and HMX (Octogen), and is far superior to that of TNT (Trinitrotoluene), highlighting its potential as a low‑sensitivity, thermally stable energetic material.