Recent 10-year development on surface modification of polymeric hollow fiber membranes via surface coating approach for gas separation: a review

Polymeric membranes have emerged as a competitive technology in gas separation processes due to their notable energy efficiency, environmentally friendly attributes and minimal system footprint. To enhance the performance of conventional polymeric membranes, significant research efforts have been dedicated to modifying their surface properties in the last decade. Among the various techniques explored, membrane surface modification using coating methods, such as dip-coating, spray-coating, grafting and interfacial polymerization stands out as one of the most popular and straightforward approaches. Scientists have utilized a diverse array of coating solutions comprising either polymeric materials or hybrid materials in these methods, yielding promising outcomes. This article aims to present a comprehensive review of the advancements made in surface coating approaches employed for modifying hollow fiber membrane surfaces over the past decade. The review encompasses an evaluation of how different coating approaches and solutions affect the surface's physicochemical properties and the gas separation performance of the membranes. Furthermore, the article delves into discussing technical challenges associated with these surface coating approaches, providing an insightful analysis. Lastly, the review concludes by outlining perspectives and recommending future research directions for this area of study, highlighting the potential avenues for innovation and advancement in surface-coated hollow fiber membranes for gas separation applications.