Synthesis of Green and Red-Emitting Polymethyl Methacrylate Composites Grafted from ZnAl 2 O 4 :Mn-Bonded GO via Surface-Initiated Atom Transfer Radical Polymerization.

A novel dual green and red-emitting photoluminescent polymer composite ZnAl 2 O 4 :Mn-bonded GO/polymethyl methacrylate (PMMA) was synthesized in a single-step reaction by surface-initiated atom transfer radical polymerization (SI-ATRP). The polymer chain was surface-initiated from the ZnAl 2 O 4 :Mn/GO, and the final products have a homogenous photoluminescent property from ZnAl 2 O 4 :Mn and better mechanical properties strengthened by graphene oxide (GO). The morphologies of ZnAl 2 O 4 :Mn/GO and the polymer composites were verified by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). X-ray diffraction analysis (XRD) revealed the two valence states of Mn (Mn 2+ , Mn 4+ ) existing in the ZnAl 2 O 4 host lattice, while Fourier-transform infrared spectroscopy (FTIR) spectra proved the transference of the active group, C-Br, from the initiator to the monomer during the polymerization. Gel permeation chromatography (GPC) shows the narrow dispersity of polymer composites fabricated through SI-ATRP. The SEM and FTIR results show the successful 'graft' of the polymer chains from the surface of ZnAl 2 O 4 :Mn/GO. The dual green and red-emitting polymer composites were synthesized, confirmed by the photoluminescence (PL) and photoluminescence excitation (PLE) results.