Selective adsorption and separation of CO2 from flue gas and landfill gas mixtures have drawn great attention in industry. Porous MOF materials are promising alternatives to achieve such separations; however, the stability in the presence of moisture must be taken into consideration. Herein, we have constructed a microporous metal-organic framework (MOF) {[Co(OBA)(L)0.5 ]⋅S}n (IITKGP-8), by employing a V-shaped organic linker with an azo-functionalized N,N' spacer forming a 3D network with mab topology and 1D rhombus-shaped channels along the crystallographic 'b' axis with a void volume of 34.2 %. The activated MOF reveals a moderate CO2 uptake capacity of 55.4 and 26.5 cm3  g-1 at 273 and 295 K/1 bar, respectively, whereas it takes up a significantly lower amount of CH4 and N2 under similar conditions and thus exhibits its potential for highly selective sorption of CO2 with excellent IAST selectivity of CO2 /N2 (106 at 273 K and 43.7 at 295 K) and CO2 /CH4 (17.7 at 273 K and 17.1 at 295 K) under 1 bar. More importantly, this MOF exhibits excellent moisture stability as assessed through PXRD experiments coupled with surface area analysis.