A nitro-decorated NbO-type metal–organic framework with a highly selective CO2 uptake and CH4 storage capacity

A nitro-decorated NbO-type metal–organic framework, Cu2NTPTB (NJU-Bai 14; H4NTPTB = 2′-nitro-[1,1′:4′,1′′-terphenyl]-3,3′′,5,5′′-tetracarboxylic acid), was synthesized and structurally characterized. It exhibited high permanent porosity with a BET surface area of 2384 m2 g−1, improved adsorption selectivity of CO2/CH4 (6.5) and CO2/N2 (20.8) at 298 K and 1 bar, high excess unsaturation CO2 uptake (94.0 wt%) at 273 K and 20 bar, and high methane total uptake of 184 cm3 cm−3 at 290 K and 35 bar.