Triazole-Triazine-Tetrazine Co-Constructed Nitrogen-Rich Covalent Organic Frameworks With Tunable H₂O₂ Photosynthesis and Energetic Performance by Stepwise Oxidation Strategy

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 H₂O₂ (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.