Despite the recent astronomical success of organic-inorganic perovskite solar cells (PSCs), the impact of microscale film inhomogeneities on device performance remains poorly understood. In this work, we study CH3NH3PbI3 perovskite films using cathodoluminescence in scanning transmission electron microscopy and show that localized regions with increased cathodoluminescence intensity correspond to iodide-enriched regions. These observations constitute direct evidence that nanoscale stoichiometric variations produce corresponding inhomogeneities in film cathodoluminescence intensity. Moreover, we observe the emergence of high-energy transitions attributed to beam induced iodide segregation, which may mirror the effects of ion migration during PSC operation. Our results demonstrate that such ion segregation can fundamentally change the local optical and microstructural properties of organic-inorganic perovskite films in the course of normal device operation and therefore address the observed complex and unpredictable behavior in PSC devices.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acs.nanolett.5b05181 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Synergistic Improvement of Narrow Bandgap PbS Quantum Dot Solar Cells through Surface Ligand Engineering, Near-Infrared Spectral Matching, and Enhanced Electrode Transparency.
ACS Appl Mater Interfaces
January 2025
CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India.
The tunability of the energy bandgap in the near-infrared (NIR) range uniquely positions colloidal lead sulfide (PbS) quantum dots (QDs) as a versatile material to enhance the performance of existing perovskite and silicon solar cells in tandem architectures. The desired narrow bandgap (NBG) PbS QDs exhibit polar (111) and nonpolar (100) terminal facets, making effective surface passivation through ligand engineering highly challenging. Despite recent breakthroughs in surface ligand engineering, NBG PbS QDs suffer from uncontrolled agglomeration in solid films, leading to increased energy disorder and trap formation.
View Article and Find Full Text PDFObservation of Large Low-Field Magnetoresistance in Layered (NdNiO):NdO Films at High Temperatures.
Adv Mater
January 2025
State Key Laboratory for Manufacturing Systems Engineering, Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, China.
Large low-field magnetoresistance (LFMR, < 1 T), related to the spin-disorder scattering or spin-polarized tunneling at boundaries of polycrystalline manganates, holds considerable promise for the development of low-power and ultrafast magnetic devices. However, achieving significant LFMR typically necessitates extremely low temperatures due to diminishing spin polarization as temperature rises. To address this challenge, one strategy involves incorporating Ruddlesden-Popper structures (ABO):AO, which are layered derivatives of perovskite structure capable of potentially inducing heightened magnetic fluctuations at higher temperatures.
View Article and Find Full Text PDFFrom synthesis to application: a review of BaZrS chalcogenide perovskites.
Nanoscale
January 2025
Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, USA.
Chalcogenide perovskites are gaining prominence as earth-abundant and non-toxic solar absorber materials, crystallizing in a distorted perovskite structure. Among these, BaZrS has attracted the most attention due to its optimal bandgap and its ability to be synthesized at relatively low temperatures. BaZrS exhibits a high light absorption coefficient, excellent stability under exposure to air, moisture, and heat, and is composed of earth-abundant elements.
View Article and Find Full Text PDFLiOH Additive Triggering Beneficial Aging Effect of SnO Nanocrystal Colloids for Efficient Wide-Bandgap Perovskite Solar Cells.
ACS Appl Mater Interfaces
January 2025
State Key Laboratory of Wide-Bandgap Semiconductor Devices and Integrated Technology, Xidian University, Xi'an 710071, PR China.
Commercial SnO nanocrystals used for producing electron transporting layers (ETLs) of perovskite solar cells (PSC) are prone to aggregation at room temperature and contain many structural defects. Herein, we report that the LiOH additive can simultaneously delay the aggregation and donate the beneficial aging effect to SnO nanocrystals. The resulting SnO ETLs show the desired characteristics, including a broadened absorption range, reduced defects, improved transporting properties, and decreased work function.
View Article and Find Full Text PDFStretchable Primary-Blue Color-Conversion Layer: Crystallization of Phase-Engineered Perovskite Nanocrystals in an Organic Matrix.
ACS Nano
January 2025
Division of Materials Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea.
Although the use of ultraviolet (UV) light-emitting diode backlight with red, green, and blue color-conversion layers (CCLs) in displays simplifies the manufacturing process and improves display uniformity, research on blue CCLs remains limited and has been mostly reported in the sky-blue region (> 470 nm), which is insufficient to satisfy the Rec. 2020 color standard. As halide perovskites offer a high extinction coefficient, color purity, and photoluminescence quantum yield (PLQY), they become highly competitive color-converting materials for CCLs.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!