Efficient NIR light blockage with matrix embedded silver nanoprism thin films for energy saving window coating

Highly efficient composite films, consisting of silica coated and functionalised silver nanoprisms (SNPs), are presented as a low-cost material to reduce thermal radiation flux with low impact on daylight transmission compared to similar solutions. The SNPs are covalently embedded in a poly(methyl methacrylate) (PMMA) matrix which prevents both leaking of the SNPs and aggregation within the matrix, thus enabling the formation of stable thin films with controllable dispersion. The cast thin films show absorbance in the IR region above 700 nm and a figure of merit of around 1, which is achieved with very thin films and low material consumption.