Perovskite has shown attractive optoelectronic performances and is a potential material in lighting, anti-counterfeiting, sensor, and other optoelectronic devices. Recently, spin-coating has been widely used in fabricating high-performance perovskite films, but it is difficult to process and apply in practice. In this paper, the CsPbBr 3 /Cs 4 PbBr 6 composite perovskite quantum dots with photoluminescence quantum yield of 36% and high storage stability were prepared by using room temperature ligand-assisted precipitation method and controlling the proportion of CsBr/PbBr 2 . In addition, the composite perovskite was ground and dispersed in the inks system. After adjusting the composition and ratio of the resin components, the inks were suitable for screen printing with a viscosity of 2439 mPa•s, an initial dryness of 25 mm/30 s, and a thorough dryness of 100 s/100 μm. By printing, the perovskite films exhibited high coverage, strong green emission, and outstanding fluorescence recovery ability after exposure to water. Screen printing perovskite inks have the characteristic of being patternable, which provides a solution for preparing a perovskite film in the application.
Over the past few years, ionic liquids (ILs) have been widely reported as reaction media for reverse atom transfer radical polymerization (ATRP). In particular, almost all the ILs with the structure [Hmim][RCOO] (R represents an alkyl group) have been used as ligands for a reverse ATRP system. However, the facile, simple and low-cost ILs, 1-alkyl-3-methylimidazole chloride ([Rmim][Cl]), have rarely been employed as ligands for reverse ATRP. In this article, a [Rmim][Cl] was successfully employed as a ligand for the reverse ATRP of methyl methacrylate with Fe(III) as catalyst and 2,2′-azobisisobutyronitrile as initiator. The key to success is to adjust the FeCl3/[Rmim][Cl] molar ratio value to 1 : 1. The results indicated that the polymerization with [Rmim][Cl] as a ligand proceeded in a controlled/“living” fashion, as evidenced by the first-order kinetic plot, low polydispersity index values, and increase in polymer molecular weight with monomer conversion. The effects of various experimental parameters, including different catalysts, reaction temperatures, solvents, and molar ratios of FeCl3/[Rmim][Cl], on the polymerization were investigated in detail. Furthermore, 1H NMR and gel permeation chromatography analyses confirmed the halogen-containing chain-end functionality of the resultant polymer.