Temperature Dependence of the Optical Transition Characteristics of MAPbClBr Single Crystals

TL;DR

This study investigates how temperature affects the optical transition properties of MAPbClBr single crystals, revealing composition-dependent behaviors and phase transition characteristics relevant for tunable semiconductor applications.

Contribution

It provides a comprehensive analysis of temperature-dependent photoluminescence in mixed halide methylammonium lead halide crystals, highlighting the absence of structural phase transition in mixed compositions.

Findings

MAPbCl3 and MAPbBr3 show sharp exciton transitions with phase transitions.

Mixed halide crystals do not exhibit structural phase transitions.

Temperature influences PL intensity, peak energy, and FWHM.

Abstract

Methylammonium-lead-halide compounds have emerged as promising bandgap engineering materials due to their ability to fine-tune the energy gap through halogen element mixing. We present a comprehensive investigation of the temperature-dependent photoluminescence (PL) transition characteristics exhibited by single crystals of chlorine and bromine-based methylammonium lead halides. MAPbCl3 and MAPbBr3 crystals exhibit a distinct sharp free exciton transition with an abrupt transition behavior associated with the structural phase transition as the temperature varies. However, when the two halogen elements are mixed within the crystals, no structural phase transition is observed. This study explores the temperature-dependent variations in integrated PL intensity, full-width-half-maximum, and peak transition energy of the crystals. The obtained results discuss the intricate interplay between temperature, crystal structure, and composition, providing valuable insights into the optical properties and potential applications of organic-inorganic hybrid methyl-ammonium lead halide single crystals as tunable energy gap semiconductor materials.