Advances in surface modification and functionalization for tailoring the characteristics of thin films and membranes via chemical vapor deposition techniques

Abstract

Advanced materials are among the prime drivers for technological revolutions and transformation in quality of lives. Over time, several modification techniques have emerged enabling development of novel materials with extraordinary features. The present review aims to introduce various promising chemical and physical surface modification techniques instrumental for tailoring the characteristics of thin films and membranes. Meticulous discussions are provided over chemical vapor deposition (CVD) techniques evolved for addressing the demands for materials with desired functionalities. Also, essential criteria for the selection of substrates, modifying and precursor materials for an effective CVD modification are elaborated. Investigations are extended to unraveling the role of various process parameters on the quality and properties of deposition. Special attention is paid to the significance and performance of CVD‐based membranes and thin films for industrial applications ranging from desalination and water treatment to energy and environment, biomedical and life science as well as packaging. The goal has been to establish a scientific platform for a timely tracking of the prevailing trends in exploitation of CVD techniques and highlighting the unexplored opportunities. This also helps in identification of the scientific and technical gaps and setting directions for further progress in the fields of thin films and membranes.

Advancements in defect engineering of two-dimensional nanomaterial-based membranes for enhanced gas separation

“…This advancement is exemplified by the development of a series of gas separation membranes via chemical vapor deposition, where the inherent defects exhibit a sieving effect on gas molecules, thereby surpassing Knudsen selectivity in mixed gas selectivity. 34,[36][37][38][39]…”

Next-Generation Water Treatment: Exploring the Potential of Biopolymer-Based Nanocomposites in Adsorption and Membrane Filtration

“…The discussion extends to the cost-effectiveness and economic value of using polymeric hybrid materials based on carbon nanotubes as nano-sorbents for water purification [ 239 ]. Notably, these nanocomposite membranes have demonstrated higher flux, improved fouling resistance, and prolonged operational lifetime compared to traditional membranes [ 240 , 241 , 242 ]. Surface modification techniques, such as grafting or chemical modification, can introduce functional groups that repel foulants or enhance the interaction with specific contaminants, improving separation efficiency and reducing fouling propensity [ 240 ].…”

“…Notably, these nanocomposite membranes have demonstrated higher flux, improved fouling resistance, and prolonged operational lifetime compared to traditional membranes [ 240 , 241 , 242 ]. Surface modification techniques, such as grafting or chemical modification, can introduce functional groups that repel foulants or enhance the interaction with specific contaminants, improving separation efficiency and reducing fouling propensity [ 240 ]. For example, a PVA–silica nanofiber membrane modified with thiol exhibited superior Cu(II) ion adsorption compared to a PVA nanofiber membrane.…”

Designing Organic and Hybrid Surfaces and Devices with Initiated Chemical Vapor Deposition (iCVD)

“…The penetration of vapor‐phase monomers into the confines of porous materials makes iCVD valuable for the surface modification of membranes used in separation and purification processes. [ 22–24 ] Figure 2E,F show a conformal iCVD coating over a metal mesh used to achieve efficient oil‐water separation. [ 25 ] For durability, the iCVD nanolayer had bilayer design with an entangled interface and the first layer was grafted to the metal using a crosslinked polymeric network (Section 3.2).…”