From molecular salt to layered network: cation-driven tuning of band gap, structure, and charge transport in A <sub>3</sub> Bi <sub>2</sub> I <sub>9</sub> (A = Cs, Rb) perovskites
Mohamed Bouzidi, Mohamed Ben Bechir, Dhaifallah R. Almalawi, Idris H. Smaili, Fahad Aljuaid
Abstract
. Raman spectroscopy highlights distinct vibrational modes, influenced by their structural differences. Space charge limited current (SCLC) measurements indicate varying threshold voltages and trap densities. Impedance spectroscopy and Jonscher's power law analysis reveal different polaron tunneling mechanisms in each compound. Ultrafast transient absorption spectroscopy shows the formation of self-trapped states upon photoexcitation, linked to lattice distortion and the formation of small polarons, which affect electrical conductivity.
Topics & Concepts
HalideBand gapSalt (chemistry)Charge (physics)OptoelectronicsMaterials scienceEnvironmentally friendlyChemistryInorganic chemistryNanotechnologyPhysical chemistryPhysicsBiologyEcologyQuantum mechanicsPerovskite Materials and ApplicationsSolid-state spectroscopy and crystallographyLuminescence Properties of Advanced Materials