High-surface-area ordered mesoporous oxides for continuous operation in high temperature energy applications

摘要

The collapse of nanostructures at high temperature is one of the main drawbacks for the implementation of nanomaterials in some energy applications. An exciting virtual non-degradation up to 1000 °C is presented here for ordered mesoporous gadolinia doped ceria. By using the nanocasting method based on the KIT-6 template, the long-term stability of the material is achieved when extending the self-limited grain growth regime, recently proved for thin films, to open three-dimensional structures. Contrary to widely employed high temperature stabilization treatments inside the template, this work shows the advantage of a counterintuitive and cost-effective thermal treatment at intermediate temperatures, lower than the operation temperature. The evolution of the mesostructure with time at high temperatures, ranging from 800 °C to 1100 °C, is reported in terms of the microstructure (grain size and specific surface area) and catalytic activity (redox ability and oxygen storage capacity). The possibility of extension of this methodology to almost all metal oxides and the capability of working at temperatures significantly over the state-of-the-art open a new avenue for the use of these high-surface area 3D nanostructures in up-to-now forbidden high temperature energy applications such as solid oxide fuel/electrolysis cells, gas separation membranes or high temperature catalysis.