MMMs have opened up a new window in gas separation and purification applications, but the actual viability can be reckoned on the basis of performance achieved in realistic feed conditions. This research highlights the selection of silica-decorated graphene for the first time to prepare nanocomposite membranes. XRD, Raman, and UV validated the existence of different fillers within the host Polysulfone (PSf), while TEM authenticated their distribution. The burst strength and thermal properties were also investigated for the prepared samples. This study also covered a prudent step towards resolving the dominant ingredients, which routinely appraise the stability and durability of the membranes. These indexes are long-term gas permeation stability up to 120 hours coupled with sustainability against hydrothermal and chemical resistance under various conditions similar to real-life gas separation applications. Finally, the report demonstrates that the nanohybrid integrated membrane systems display optimum performance and stability in all the aspects as compared to their parent counterparts: PSf/mSiO2 and PSf/GO.