Nanoscale Chemical Heterogeneity Dominates the Optoelectronic Response over Local Electronic Disorder and Strain in Alloyed Perovskite Solar Cells

Abstract

Halide perovskites perform remarkably in optoelectronic devices including tandem photovoltaics. However, this exceptional performance is striking given that perovskites exhibit deep charge carrier traps and spatial compositional and structural heterogeneity, all of which should be detrimental to performance. Here, we resolve this long-standing paradox by providing a global visualisation of the nanoscale chemical, structural and optoelectronic landscape in halide perovskite devices, made possible through the development of a new suite of correlative, multimodal microscopy measurements combining quantitative optical spectroscopic techniques and synchrotron nanoprobe measurements. We show that compositional disorder dominates the optoelectronic response, while nanoscale strain variations even of large magnitude (~1 %) have only a weak influence. Nanoscale compositional gradients drive carrier funneling onto local regions associated with low electronic disorder, drawing carrier recombination away from trap clusters associated with electronic disorder and leading to high local photoluminescence quantum efficiency. These measurements reveal a global picture of the competitive nanoscale landscape, which endows enhanced defect tolerance in devices through spatial chemical disorder that outcompetes both electronic and structural disorder.

arXiv comment26 pages, 4 figures

References in corpus (8)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Response to comment on "Resolving spatial and energetic distributions of trap states in metal halide perovskite solar cells"
• Intense Internal and External Fluorescence as Solar Cells Approach the Shockley-Queisser Efficiency Limit
• The perovskite/transport layer interfaces dominate non-radiative recombination in efficient perovskite solar cells
• Local Crystal Misorientation Influences Non-Radiative Recombination
• Localization landscape theory of disorder in semiconductors II: Urbach tails of disordered quantum well layers
• Strain-Tuning of the Optical Properties of Semiconductor Nanomaterials by Integration onto Piezoelectric Actuators
• Maximising and Stabilising Luminescence in Metal Halide Perovskite Device Structures

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