An electroless-plating-like solution deposition approach for large-area flexible thin films of transition metal oxide nanocrystals

Abstract

We developed a novel Electroless-Plating-Like Solution Deposition (EPLSD) approach for realization of large-area flexible thin films of transition metal oxides (TMOs) with d⁰ configuration. This EPLSD approach was triggered at 80 °C through the redox reaction between Peroxo-Metal Complex (PMC, including Peroxo-Titanium Complex (PTC), Peroxo-Vanadium Complex (PVC), and Peroxo-Molybdenum Complex (PMoC)) and organic conductive electroactive monomers (EDOT, pyrrole, and aniline). In the typical EPLSD process, a layer of organic conductive electroactive polymer monomers was absorbed onto the surface of the flexible polymer substrate by dip coating, and these pretreated flexible substrates were then immersed into an aqueous PMC solution for the EPLSD process. After the EPLSD process at 80 °C for 30 min, large area (40 cm × 300 cm) flexible thin films of metal oxide nanocrystals, including TiO_x, VO_x, and MoO_x, nanocrystal films can be achieved. This low-temperature EPLSD process is advantageous for flexible substrates and may easily realize TMO films on flexible substrates with different geometric shapes.