Melamine-derived nitrogen-doped carbon foam supported bimetallic NiZn-MOFs as an efficient adsorbent for CH4 storage

A current challenge for natural gas adsorbed storage technology is to find specialized adsorbent materials that are able to store and deliver large amounts of methane (CH 4 ) near room temperature and at low pressures. In this study, bimetallic MOFs is supported on nitrogen-doped carbon foam derived from melamine (MC@NZn) by vacuum impregnation process as an adsorbent for CH 4 storage. The nitrogen-doped carbon foam with macroporous internetwork combined with high surface area and micro-/mesoporous structure of the NiZn-MOF leads a hierarchical porous structure, which provides efficient and rapid pathways for the penetration of CH 4 molecules and more active sites for CH 4 adsorption. Experimental results show that MC@NZ4 exhibits a CH 4 adsorption capacity of 105.80 cm 3 ·g -1 under 298 K and 60 bar with isosteric heat of adsorption of 10.71 kJ·mol -1 . Furthermore, MC@NZ4 achieves a CH 4 /N 2 adsorption selectivity of 5.63, indicating its potential for CH 4 adsorption. This work provides a simple method to combine MOF powders with three-dimensional skeleton substrate material to fabricate monolithic solid porous materials, which can find potential applications in gas adsorption.