Phase transition and photoluminescence properties in a hybrid layered perovskite: (cyclohexylmethylammonium)2PbBr4

In addition to the appealing semiconducting properties displayed by layered Sn-II or Pb-II halidometallates, intriguing phase-transition-induced properties, such as dielectric and ferroelectric properties, have recently been found by us in (benzyl-ammonium) 2PbCl4 and (cyclohexylammonium)(2)PbBr4-4xI4x (x = 0-1). The simple molecular structures of the layered compounds allow further chemical design for the modification of the physical properties. Thus, we extended the study to layered compounds templated by structurally similar organic cations to achieve future functions. Here, we report the design of a layered perovskite templated by cyclohexylmethylammonium cations, namely, bis[(cyclohexylmethyl) ammonium] tetrabrom-idolead( II). We found that this compound exhibits not only photoluminescence with a remarkably high efficiency (quantum yield = 21 %) but also interesting phase-transition-related physical properties, such as striking dielectric responses. These results reveal the great application potential of organic-inorganic hybrid compounds in the field of phase-transition multifunctional materials. More interesting phase-transition crystals are expected to be tailored in the future by taking advantage of the richness of layered perovskites.