Ion-conducting polymer thin films via chemical vapor deposition polymerization

Ion-conducting polymers (ICPs), benefiting from the movement of ions instead of electrons, have attracted significant interest in various scientific and technological fields, including drug delivery, water purification, and electrochemical devices. This review aims to highlight recent advances in the synthesis of ICP thin films, with a particular focus on chemical vapor deposition (CVD) technologies. Traditional solution-based methods for ICP thin film deposition face challenges, including non-uniformity, low-throughput manufacturing, and the generation of hazardous wastes. In comparison, CVD eliminates the drawbacks associated with solution-based processes. They offer precise control film properties, including high purity, conformal coating, delicate control over thickness, etc. This review organizes the latest developments in CVD-based ICP synthesis, based on material properties and the synthesis strategy, into direct deposition and post-polymerization modification, ionogels, hydrogels, and ultrathin siloxane or silazane-based polymer films. By providing an up-to-date review of the materials and synthesis, we aim to position CVD polymerization as an effective strategy for future materials development/production and device fabrication in energy, sustainability, and healthcare where ion conductivity is desired.