Pressure-induced giant emission enhancement, large band gap narrowing and rich polymorphism in two-dimensional 1,2,4-triazolium lead bromide perovskite.

ABSTRACT: Layered lead halide perovskites are attractive materials for optoelectronic applications. In this work, temperature-dependent photoluminescence (PL) as well as pressure-dependent Raman and PL studies of lead bromide comprising small disc shape 1,2,4-triazolium cations (Tz⁺) are reported. Temperature-dependent studies reveal that at room-temperature (RT) Tz₂PbBr₄ exhibits narrow emission at 2.89 eV related to a free exciton (FE). At low temperature, three new narrow and weakly red-shifted bands as well as a very broad and strongly red-shifted band near 2.2 eV appear. The narrow and broad bands are attributed to self-trapped excitons (STEs) trapped by shallow and deep donors (acceptors), respectively. Pressure-dependent Raman studies revealed the presence of

SUBMITTER: Maczka M 

PROVIDER: S-EPMC11618524 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature