Morphology and temperature dependence of a dual excitonic emissive 2D bromoplumbate hybrid perovskite: the key role of crystal edges

Abstract

Halide perovskites exhibiting broad band emission have attracted increasing attention since their discovery in 2014 because of their potentiality in lighting applications. Here, we report a new bromoplumbate organic-inorganic perovskite...

Bromination of organic spacer impacts on the structural arrangement, phase transitions, and optical and electrical properties of a hybrid halide compound:[(CH3)3N(CH2)3Br]2PdBr4

“…The later temperature transition can be attributed to a congruent melting of the organic component, similar to observation in other hybrid halide materials. 53,54 The calculated entropy of the first peak aids in determining the type of transition which is equal to 5.64 J mol À1 K À1 and 5.82 J mol À1 K À1 with heating rates of 10 K min À1 and 5 K min À1 , respectively. These values exceed 2 J mol À1 K À1 which it is usually considered as an indication of an order-disorder type transition.…”

Crystal structure, semiconducting and photoluminescence (PL) properties of hybrid tin perovskite-like materials: [Cl–(CH2)2–NH3]2SnCl6 and [Cl–(CH2)2–NH3]2SnBr5.65Cl0.35

“…In fact, the distribution of the structural defects, often active as emissive traps, is strictly dependent on the sample morphology. 13,45,46 The photoluminescence analysis of [Cl-(CH 2 ) 2 -NH 3 ] 2 Sn-Br 5.65 Cl 0.35 (2) crystalline powders was performed following the same protocol as that for compound (1). However, differently from compound (1), compound (2) displays only a broad emission spectrum centered at 475 nm (Fig.…”

“…10 Luckily, the ability to control fundamental material properties by adjusting arrangements of molecules gives a rich platform for designing optical, phase change, luminescence and ferroelectric materials. [11][12][13][14][15] In the reported hybrid perovskite materials, the majority consist of organic ammonium cations and inorganic metal salts of Pb(II) halide anions. 16,17 For instance, the hybrid lead halide perovskite family with the formula [(CH 3 ) 2 NH 2 ]PbX 3 (X = Cl À , Br À ) is the most attractive owing to its unique 3D structure and some fascinating optoelectronic properties.…”

Controlling glass forming kinetics in 2D perovskites using organic cation isomers

“…19 Metals 32 and some chalcogenides, 31 particularly Ge-Sb-Te (GST), are known to possess such characteristics. Given the wide range of available organic cations and inorganic frameworks capable of forming 2D or 1D MHPs 33 and the ability to tune their thermal properties, including the melting temperature (T m ) with a range of over 150 °C, [34][35][36][37][38][39][40][41] it is conceivable that within the MHP family, a wide range of glassforming ability and varying crystallization kinetics can be achieved. The previously reported S(1-1)NPB perovskite, known for its exemplary glass-forming ability, exhibits a low T m of 175 °C and a CCR of as low as 0.3 °C s −1 with slow glass-crystal transformation kinetics.…”