Ionothermal synthesis, structure and optical properties of three new organic–inorganic hybrid imidazolium bromoplumbate complexes

By heating imidazolium bromide-based ionic liquids with Pb(NO3)2 under ionothermal conditions, we have successfully generated three imidazolium bromoplumbates, namely, [(PMI)PbBr3]n (1), [(AMI)PbBr3]n (2) and [(HMI)PbBr3]n (3) (PMI = 1-propyl-3-methylimidazolium, AMI = 1-allyl-3-methylimidazolium, HMI = 1-hexyl-3-methylimidazolium). Compounds 1–3 are isomorphic and exhibit unusual supramolecular organization wherein dialkylimidazolium cations arrange themselves in a cylindrical fashion giving rise to channel structures, which are further occupied by the 1D zigzag [PbBr3]n inorganic chains. The UV–vis diffuse reflectance spectra and luminescence measurements indicate that all compounds are potential semiconductor and photoluminescence materials.

Graphical AbstractThree imidazolium bromoplumbate organic–inorganic hybrid solids were obtained under ionothermal conditions and exhibit unusual supramolecular organization wherein dialkylimidazolium cations arrange themselves in a cylindrical fashion giving rise to channel structures, which are further occupied by the 1D zigzag [PbBr3]n inorganic chains.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch Highlights► Dialkyl-imidazolium bromide-based ionic liquids are utilized as solvent. ► Crystal structures for three imidazolium bromoplumbate hybrid solids. ► Strong blue photoluminescence generated from the zigzag [PbBr3]n chain. ► Three compounds are potential semiconductor materials.