A Review of Alkali Tungsten Bronze Nanoparticles for Applications in Plasmonics

The optimal material for plasmonic applications is an electrical conductor with low damping losses, high chemical and thermal stability, simple low-cost synthetic methods, and a resonance frequency that can be tuned to suit a desired application. To date, plasmonic applications have predominantly relied on Au or Ag, but these materials are limited respectively by high damping losses and rapid corrosion. In the search for alternative plasmonic materials, the alkali tungsten bronzes have been identified as possible candidates, as they display many of the features of the optimal plasmonic material. In this review, we first describe the crystallography, electronic structure, synthesis methods and plasmonic behaviour of the tungsten bronzes. A range of plasmonic applications for tungsten bronze nanoparticles, including solar-control filtering, plasmonic photocatalysis and plasmonic photothermal therapy, are then discussed.