High-Capacity Gas Storage by a Microporous Oxalamide-Functionalized NbO-Type Metal–Organic Framework

Abstract

A microporous oxalamide-functionalized NbO-type metal–organic framework, HNUST-3, has been designed and synthesized by self-assembling [Cu 2 (COO) 4 ] paddlewheel SBUs and a novel tetracarboxylate ligand with linking oxalamide groups. HNUST-3 represents the first example of a porous oxalamide-functionalized MOF, which exhibits a high BET surface area of 2412 m 2 ·g –1, large H 2 uptake (unsaturated total capacity of 6.1 wt % at 20 bar and 77 K), and excellent CH 4 storage (135.8 cm 3 (STP)cm –3 at 20 bar and 298 K) as well as high CO 2 adsorption capacity (20.2 mmol·g –1 at 20 bar and 298 K) with good selectivity for CO 2 over CH 4 (7.9) and N 2 (26.1) at 298 K.