Low-Temperature, Universal Synthetic Route for Mesoporous Metal Oxides by Exploiting Synergistic Effect of Thermal Activation and Plasma

Mesoporous metal oxides exhibit excellent physicochemical properties and are widely used in various fields, including energy storage/conversion, catalysis, and sensors. Although several soft-template approaches are reported, high-temperature calcination for both metal oxide formation and template removal is necessary, which limits direct synthesis on a plastic substrate for flexible devices. Here, a universal synthetic approach that combines thermal activation and oxygen plasma to synthesize diverse mesoporous metal oxides (V2O5, V6O13, TiO2, Nb2O5, WO3, and MoO3) at low temperatures (150-200 degrees C), which can be applicable to a flexible polymeric substrate is introduced. As a demonstration, a flexible micro-supercapacitor is fabricated by directly synthesizing mesoporous V2O5 on an indium-tin oxide-coated colorless polyimide film. The energy storage performance is well maintained under severe bending conditions. The synergistic effect of thermal activation and plasma enabled low-temperature synthesis (150-200 degrees C) of various mesoporous metal oxide (V2O5, V6O13, TiO2, WO3, Nb2O5, and MoO3), suitable for flexible polymeric substrates. As a proof of concept, the direct synthesis of mesoporous V2O5 is demonstrated on an indium-tin oxide-coated polyimide film and its application as electrode materials.image