Chemical control of the dimensionality of the octahedral network of solar absorbers from the CuI–AgI–BiI3 phase space by synthesis of 3D CuAgBiI5

DOI: 10.1021/acs.inorgchem.1c02773

Authors: Harry C. Sansom (University of Oxford) , Leonardo R. V. Buizza (University of Oxford) , Marco Zanella (University of Liverpool) , James T. Gibbon (University of Liverpool) , Michael Pitcher (University of Liverpool) , Matthew S. Dyer (University of Liverpool) , Troy D. Manning (University of Liverpool) , Vinod R. Dhanak (University of Liverpool) , Laura M. Herz (University of Oxford) , Henry J. Snaith (University of Oxford) , John B. Claridge (University of Liverpool) , Matthew J. Rosseinsky (University of Liverpool)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Inorganic Chemistry , VOL 30

State: Published (Approved)
Published: November 2021

Abstract: A newly reported compound, CuAgBiI5, is synthesized as powder, crystals, and thin films. The structure consists of a 3D octahedral Ag+/Bi3+ network as in spinel, but occupancy of the tetrahedral interstitials by Cu+ differs from those in spinel. The 3D octahedral network of CuAgBiI5 allows us to identify a relationship between octahedral site occupancy (composition) and octahedral motif (structure) across the whole CuI–AgI–BiI3 phase field, giving the ability to chemically control structural dimensionality. To investigate composition–structure–property relationships, we compare the basic optoelectronic properties of CuAgBiI5 with those of Cu2AgBiI6 (which has a 2D octahedral network) and reveal a surprisingly low sensitivity to the dimensionality of the octahedral network. The absorption onset of CuAgBiI5 (2.02 eV) barely changes compared with that of Cu2AgBiI6 (2.06 eV) indicating no obvious signs of an increase in charge confinement. Such behavior contrasts with that for lead halide perovskites which show clear confinement effects upon lowering dimensionality of the octahedral network from 3D to 2D. Changes in photoluminescence spectra and lifetimes between the two compounds mostly derive from the difference in extrinsic defect densities rather than intrinsic effects. While both materials show good stability, bulk CuAgBiI5 powder samples are found to be more sensitive to degradation under solar irradiation compared to Cu2AgBiI6.

Journal Keywords: Spinel; Crystal structure; Layers; Chemical structure; Diffraction

Diamond Keywords: Photovoltaics; Semiconductors

Subject Areas: Chemistry, Materials, Energy


Instruments: I11-High Resolution Powder Diffraction

Added On: 11/11/2021 09:04

Documents:
aelm.201800055.pdf

Discipline Tags:

Earth Sciences & Environment Sustainable Energy Systems Energy Climate Change Physical Chemistry Energy Materials Chemistry Materials Science Inorganic Chemistry

Technical Tags:

Diffraction X-ray Powder Diffraction