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
I14-Hard X-ray Nanoprobe	Multimodal microscale imaging of textured perovskite–silicon tandem solar cells Elizabeth M. Tennyson , Kyle Frohna , William K. Drake , Florent Sahli , Terry Chien-Jen Yang , Fan Fu , Jérémie Werner , Cullen Chosy , Alan R. Bowman , Tiarnan A. S. Doherty , Quentin Jeangros , Christophe Ballif , Samuel D. Stranks Acs Energy Letters DOI: 10.1021/acsenergylett.1c00568 Diamond Proposal Number(s): [20420] Open Access Show Abstract ▼ Abstract: Halide perovskite/crystalline silicon (c-Si) tandem solar cells promise power conversion efficiencies beyond the limits of single-junction cells. However, the local light-matter interactions of the perovskite material embedded in this pyramidal multijunction configuration, and the effect on device performance, are not well understood. Here, we characterize the microscale optoelectronic properties of the perovskite semiconductor deposited on different c-Si texturing schemes. We find a strong spatial and spectral dependence of the photoluminescence (PL) on the geometrical surface constructs, which dominates the underlying grain-to-grain PL variation found in halide perovskite films. The PL response is dependent upon the texturing design, with larger pyramids inducing distinct PL spectra for valleys and pyramids, an effect which is mitigated with small pyramids. Further, optimized quasi-Fermi level splittings and PL quantum efficiencies occur when the c-Si large pyramids have had a secondary smoothing etch. Our results suggest that a holistic optimization of the texturing is required to maximize light in- and out-coupling of both absorber layers and there is a fine balance between the optimal geometrical configuration and optoelectronic performance that will guide future device designs.	May 2021
I09-Surface and Interface Structural Analysis	Elucidating and mitigating degradation processes in perovskite light‐emitting diodes Zahra Andaji-Garmaroudi , Mojtaba Abdi-Jalebi , Felix U. Kosasih , Tiarnan Doherty , Stuart Macpherson , Alan R. Bowman , Gabriel J. Man , Ute B. Cappel , Hakan Rensmo , Caterina Ducati , Richard H. Friend , Samuel D. Stranks Advanced Energy Materials 11 DOI: 10.1002/aenm.202002676 Diamond Proposal Number(s): [22668] Show Abstract ▼ Abstract: Halide perovskites have attracted substantial interest for their potential as disruptive display and lighting technologies. However, perovskite light‐emitting diodes (PeLEDs) are still hindered by poor operational stability. A fundamental understanding of the degradation processes is lacking but will be key to mitigating these pathways. Here, a combination of in operando and ex situ measurements to monitor the performance degradation of (Cs0.06FA0.79MA0.15)Pb(I0.85Br0.15)3 PeLEDs over time is used. Through device, nanoscale cross‐sectional chemical mapping, and optical spectroscopy measurements, it is revealed that the degraded performance arises from an irreversible accumulation of bromide content at one interface, which leads to barriers to injection of charge carriers and thus increased nonradiative recombination. This ionic segregation is impeded by passivating the perovskite films with potassium halides, which immobilizes the excess halide species. The passivated PeLEDs show enhanced external quantum efficiency (EQE) from 0.5% to 4.5% and, importantly, show significantly enhanced stability, with minimal performance roll‐off even at high current densities (>200 mA cm−2). The decay half‐life for the devices under continuous operation at peak EQE increases from <1 to ≈15 h through passivation, and ≈200 h under pulsed operation. The results provide generalized insight into degradation pathways in PeLEDs and highlight routes to overcome these challenges.	Nov 2020

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