Metal-containing polymers can combine the electronic, optical and magnetic properties of a metal, with the solubility and processability of an organic polymer. 

In his Dalton Transactions Perspective, Wai-Yeung Wong from Hong Kong Baptist University discusses some of the recent advances and future challenges in the field of metallopolymers. 

Wong explains that organometallic polymers can show exciting photophysical properties and structural variability, which make them potentially important for industrial applications in optoelectronics and photonics. 

For example, some organometallic polymers have tuneable phosphorescence emission, making them useful for full-colour flat-panel displays. However, these materials tend to have a wide bandgap, which has so far hampered their application in photovoltaics. 

Wong discusses the trade-off problem of optimising both phosphorescence efficiency and optical gaps - lower band gaps tend to come at the expense of phosphorescence intensity. 

According to Wong, getting the right balance of these properties is crucial to these materials fulfilling their potential and finding real practical applications.