Effects of Surfactant Concentrations on Perovskite Emitters Embedded in Polystyrene

With their simple fabrication, narrow light spectrum, and color tunability, a class of materials known as perovskites are emerging as promising candidates for light emission applications. These materials, when exposed to normal atmospheric conditions show significant degradation. Improved protection has been demonstrated by embedding perovskites in polymers. Furthermore, the addition of a surfactant into the precursor solution has been shown to increase stability and allow for color tuning by exploiting quantum confinement effects. However, the effects of surfactants typically used to stabilize perovskites in solution have not been explored in this polymer embedding strategy. Here we determine the physical and optical emission changes produced by modifying the concentration of octylamine, butylamine, and oleylamine in the perovskite precursor solution prior to embedding into a polystyrene substrate. Using optical emission spectroscopy, we measure emission spectra of perovskite nanocrystals embedded in the polymer. Changes in morphology and dispersion of the perovskite particles within the polymer are observed using UV illuminated optical microscopy. XRD data suggests increased crystallinity with the addition of short chain surfactant. Our measurements in emission show that the location of the emission peak and overall shape of the emission spectra change when longer chain surfactant is added while short chain surfactant reduces nanorod formation without a significant change in particle dispersion or emission. The work suggests that increased long chain surfactant concentration prohibits perovskite crystal growth within the polymer leading to increased optical transparency and quantum confinement effects observable through photo luminescent emission