Structural variations in (001)-oriented layered lead halide perovskites, templated by 1,2,4-triazolium

DOI: 10.1039/D0DT02936J

Authors: Yuan-yuan Guo (University of St Andrews) , Lin-jie Yang (University of St Andrews) , Jason A. Mcnulty (University of St Andrews) , Alexandra M. Z. Slawin (University of Liverpool) , Philip Lightfoot (University of St Andrews)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Dalton Transactions , VOL 119

State: Published (Approved)
Published: November 2020
Diamond Proposal Number(s): 23579

Abstract: A new hybrid lead(II) halide perovskite, (TzH)2PbCl4, ([TzH+] = 1,2,4-triazolium), adopts a (001)-oriented layered perovskite structure, which can be considered as derived from the n = 1 Ruddlesden–Popper (RP) type. Variable temperature single crystal X-ray diffraction reveals a structural phase transition in the region 125 K < T < 173 K between a high temperature, high symmetry polymorph, space group Cmcm, and a low temperature, low symmetry chiral polymorph, space group P212121, which has a tripled unit cell volume. UV-Vis spectra suggest a band gap of 3.30 eV for (TzH)2PbCl4. A second polymorph of the bromide analogue, (TzH)2PbBr4-II, is also reported, and structural relationships between all three variants are discussed.

Subject Areas: Chemistry


Instruments: I11-High Resolution Powder Diffraction