Composite panels and methods of preparation are described herein. In some embodiments, the composite panel can include a first fiber reinforcement, a polyurethane composite having a first surface and a second surface opposite the first surface, wherein the first surface is in contact with the first fiber reinforcement; and a cementitious material adjacent the first fiber reinforce-opposite the polyurethane composite. The polyurethane composite can be formed from (i) one or more isocyanates selected from the group consisting of diisocyanates, polyisocyanates, and mixtures thereof, (ii) one or more polyols, and (iii) a particulate filler. The fiber reinforcement can be formed from a woven or non-woven material, such as glass fibers. The composite panel can further include a material, such as a second fiber reinforcement and a cementitious layer, in contact with the second surface of the polyurethane composite. Articles comprising the composite panels are also disclosed.

A method of manufacturing a thin film is provided. The method includes providing a plurality of crystalline hexagonal tungsten trioxide particles, size-reducing the crystalline hexagonal tungsten trioxide particles by grinding to produce crystalline hexagonal tungsten trioxide nanostructures, and coating the crystalline hexagonal tungsten trioxide nanostructures onto a substrate to produce a thin film. An electrochromic multi-layer stack is also provided.

A method of manufacturing a thin film is provided. The method includes providing a plurality of crystalline hexagonal tungsten trioxide particles, size-reducing the crystalline hexagonal tungsten trioxide particles by grinding to produce crystalline hexagonal tungsten trioxide nanostructures, and coating the crystalline hexagonal tungsten trioxide nanostructures onto a substrate to produce a thin film. An electrochromic multi-layer stack is also provided.