Synthesis and optical characterization of poly(styrene sulphonate) films doped with neodymium (III) and co-doped with chromium (III)

This work addresses the new synthesis of poly(styrene sulphonate) (PSS) films doped with neodymium ion (Nd3+) and co-doped with chromium ion (Cr3+). NdCr–PSS films were obtained by using the sulphonated polystyrene acid (H-PSS), neodymium nitrate (Nd(NO3)3), and chromium nitrate (Cr(NO3)3) in aqueous solution. Absorption spectrum of NdCr–PSS film shows the characteristic transition bands of Nd3+ and Cr3+ in UV–Vis–NIR region. Infrared spectra indicate that the dopant is bounded to the PSS lateral groups SO3−. The selective photoluminescence displays spectra blue shift when Nd and Cr ions are incorporated on PSS films. The behavior results corroborate to decrease the interaction between aromatic rings for adjacent PSS monomers, i.e., the aggregation formation.