Search Results

You searched for all publications:

with publication states 'Published (Approved)'

Search Again...

These results only include publications that have been reviewed and processed by Diamond Light Source. To also view papers that have not yet been processed click here.

You can use the folder icon under Actions to collate papers as required. You can then click on View Folder in the left-hand navigation to review and/or download your folder.

Exact matches
Related results

2 items found (0 items not approved), displaying all items.1

Instruments / Technical Area	Publication Details	Published	Actions
E02-JEM ARM 300CF I14-Hard X-ray Nanoprobe	Exploring the structural and optical response of halide perovskites using high-energy electrons Jordi Ferrer Orri DOI: 10.17863/CAM.101921 Diamond Proposal Number(s): [19793] Show Abstract ▼ Abstract: This thesis aims to investigate the nanoscale morphology, crystallography, composition, and optoelectronic structure of halide perovskites, a promising candidate for next-generation optoelectronic materials, using high-energy electron-beam microscopy techniques. This work addresses the stability challenge of PSCs from a material science perspective by understanding and controlling their complicated nanostructure. The unique macroscopic properties of lead halide perovskites are dictated by their nanostructure, which has direct ramifications on device performance and operational stability. The thesis starts by reviewing hybrid halide perovskites and their heterogeneity at multiple lengthscales, and the different electron microscopy techniques used and developed in this work. It then reports in three experimental chapters the study of degradation mechanisms under an electron and X-ray beam using 4D-scanning transmission microscopy (4D-STEM), the development of cathodoluminescence (CL-SEM) to probe the optical properties of halide perovskites at the nanoscale, and the development of strategies to push the limits of 4D-STEM towards in-situ and operando conditions. The study demonstrates that high-energy electron probes are a powerful tool for studying perovskites at the nanoscale, and each experimental chapter addresses a specific technique development to enable new modalities of electron microscopy on halide perovskites. With these developments, this thesis yields valuable fundamental insights into the phase and operational stability of the beam-sensitive hybrid lead perovskites at the nanoscale.	Apr 2023
E02-JEM ARM 300CF I14-Hard X-ray Nanoprobe	Unveiling the interaction mechanisms of electron and X‐ray radiation with halide perovskite semiconductors using scanning nano‐probe diffraction Jordi Ferrer Orri , Tiarnan A. S. Doherty , Duncan Johnstone , Sean M. Collins , Hugh Simons , Paul A. Midgley , Caterina Ducati , Samuel D. Stranks Advanced Materials DOI: 10.1002/adma.202200383 Diamond Proposal Number(s): [25250, 20420] Open Access Show Abstract ▼ 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.	Mar 2022

Publications Database

Search Results

You searched for all publications:

Search Again...

Subject Areas (check all that apply) select all

Instruments used to collect data (check all that apply) select all

Collaborations involved (check all that apply) select all

Diamond Offline Facilities used

Relevant Technical Areas (check all that apply) select all

Menu for Anonymous User