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Recently, low-dimensional organic–inorganic hybrid metal halides have attracted considerable attention in solid-state optical application fields, especially in white-light emitting diodes (WLEDs) owing to intrinsic broadband luminescence performances. Herein, by selecting different types of organic cations as a structural decoration strategy, we designed a series of new 1D hybrid halides of A2Pb3Br10 (A = NPM, DMPDA, TMEN) based on same [Pb3Br10]4− chains composed of edge-shared [Pb3Br12]6− trimers. The low-dimensional crystal lattice results in the formation of self-trapped excitons, which leads to broadband light emissions covering the entire visible region for all A2Pb3Br10 homologues. Specifically, compound 1 exhibits yellowish-white light emission (0.34, 0.45) with a photoluminescence quantum efficiency of 2.51%. Both compounds 2 and 3 show bluish-white light emissions centered at 438 nm and 440 nm, respectively, with high color rendering index (CRI) of 96, which belongs to one of the highest values to date. The intrinsic broadband white light emissions enable them as promising candidates for single-component white-light emitting materials. [ABSTRACT FROM AUTHOR]

In recent years, low-dimensional organic–inorganic hybrid lead halide perovskites have been explored as photoluminescent (PL) materials with high photoluminescence quantum efficiencies and tunable band structures arising from the structural regulating functions of organic cations. Herein, by using a simple solution reaction, we prepared one new type of one-dimensional (1D) hybrid lead halide, namely [DMEDA]PbCl4 (DMEDA = N,N′-dimethylethylenediamine). The compound contains 1D edge sharing octahedral lead chloride [PbCl4]2− anionic chains, which are surrounded and separated by organic cations of [DMEDA]2+. This 1D structure enables the formation of self-trapped excited states that give bright yellow emission with a photoluminescence quantum efficiency (PLQE) of approximately 4.81%. A white light emitting device can also be easily fabricated by coating a sample of [DMEDA]PbCl4 on a blue light chip. Its PL stability and nature are also investigated by using various experiments. This work provides a new type of structural model to probe the PL properties and understand the structure–property relationship of low-dimensional lead halide perovskites. [ABSTRACT FROM AUTHOR]

Abstract: Ceria (CeO2) as co-catalytic material with Pt on multi-walled carbon nanotubes (Pt-CeO2/MWCNT) is synthesized by a co-precipitation method. The physicochemical characterizations of the catalysts are carried out by using transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) techniques. Electrocatalytic activities of the catalysts for methanol oxidation is examined by cyclic voltammetry and chronoamperometry techniques and it is found that Pt-CeO2/MWCNT catalysts exhibited a better activity and stability than did the unmodified Pt/MWCNT catalyst. CO-stripping results indicate the facile removal of intermediate poisoning species CO in the presence of CeO2, which is helpful for CO and methanol electro-oxidation. [Copyright &y& Elsevier]