3D honeycomb construction of N-fluorodinitromethyl substituted polynitroazoles based on hydrogen-bonded staggered conformation: Toward high-density melt-cast explosive instead of TNT

•Two N-fluorodinitromethyl substituted polynitroazoles which possess zero oxygen balance and high detonation performances have been synthesized and fully characterized.•Compact 3D honeycomb construction of N-fluorodinitromethyl substituted triazole 5a based on hydrogen-bonded staggered conformation contributes to the high single-crystal density of 1.919 g cm−3.•Polynitrotriazole 5a may be a potential candidate for TNT in the application of melt-cast explosives.