Unveiling the interaction mechanisms of electron and X‐ray radiation with halide perovskite semiconductors using scanning nano‐probe diffraction

DOI: 10.1002/adma.202200383

Authors: Jordi Ferrer Orri (University of Cambridge) , Tiarnan A. S. Doherty (University of Cambridge) , Duncan Johnstone (University of Cambridge) , Sean M. Collins (University of Leeds) , Hugh Simons (Technical University of Denmark) , Paul A. Midgley (University of Cambridge) , Caterina Ducati (University of Cambridge) , Samuel D. Stranks (University of Cambridge)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Advanced Materials

State: Published (Approved)
Published: March 2022
Diamond Proposal Number(s): 25250 , 20420

Abstract: The interaction of high-energy electrons and X-ray photons with beam-sensitive semiconductors such as halide perovskites is essential for the characterisation and understanding of these optoelectronic materials. Using nano-probe diffraction techniques, which can investigate physical properties on the nanoscale, we perform studies of the interaction of electron and X-ray radiation with state-of-the-art (FA0.79MA0.16Cs0.05)Pb(I0.83Br0.17)3 hybrid halide perovskite films (FA, formamidinium; MA, methylammonium). We track the changes in the local crystal structure as a function of fluence using scanning electron diffraction and synchrotron nano X-ray diffraction techniques. We identify perovskite grains from which additional reflections, corresponding to PbBr2, appear as a crystalline degradation phase after fluences of ∼200 e–Å–2. These changes are concomitant with the formation of small PbI2 crystallites at the adjacent high-angle grain boundaries, with the formation of pinholes, and with a phase transition from tetragonal to cubic. A similar degradation pathway is caused by photon irradiation in nano-X-ray diffraction, suggesting common underlying mechanisms. Our approach explores the radiation limits of these materials and provides a description of the degradation pathways on the nanoscale. Addressing high-angle grain boundaries will be critical for the further improvement of halide polycrystalline film stability, especially for applications vulnerable to high-energy radiation such as space photovoltaics.

Diamond Keywords: Photovoltaics; Semiconductors

Subject Areas: Materials, Energy

Diamond Offline Facilities: Electron Physical Sciences Imaging Centre (ePSIC)
Instruments: E02-JEM ARM 300CF , I14-Hard X-ray Nanoprobe

Added On: 15/03/2022 09:57

Discipline Tags:

Earth Sciences & Environment Sustainable Energy Systems Energy Climate Change Energy Materials Materials Science Perovskites Metallurgy

Technical Tags:

Diffraction Microscopy Electron Microscopy (EM) Scanning Transmission Electron Microscopy (STEM)