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The presence of excess lead iodide in halide perovskites has been key for surpassing 20% photon-to-power conversion efficiency. To achieve even higher power conversion efficiencies, it is important to understand the role of remnant lead iodide in these perovskites. To that end, we explored the mechanism facilitating this effect by identifying the impact of excess lead iodide within the perovskite film on charge diffusion length, using electron-beam-induced current measurements, and on film formation properties, from grazing-incidence wide-angle X-ray scattering and high-resolution transmission electron microscopy. Based on our results, we propose that excess lead iodide in the perovskite precursors can reduce the halide vacancy concentration and lead to formation of azimuthal angle-oriented cubic α-perovskite crystals in-between 0° and 90°. We further identify a higher perovskite carrier concentration inside the nanostructured titanium dioxide layer than in the capping layer. These effects are consistent with enhanced lead iodide-rich perovskite solar cell performance and illustrate the role of lead iodide.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6098034 | PMC |
http://dx.doi.org/10.1038/s41467-018-05583-w | DOI Listing |
Adv Mater
September 2025
Key Lab of Artificial Micro- and Nano-Structures of Ministry of Education of China, School of Physics and Technology, Wuhan University, Wuhan, 430072, China.
Sequential deposition technique is widely used to fabricate perovskite films with large grain size in perovskite solar cells (PSCs). Residual lead halide (PbI) in the perovskite film tends to be decomposed into metallic lead (Pb) under long-term heating or light soaking. Here, a chiral levetiracetam (LEV) dopant containing α-amide and pyrrolidone groups is introduced into the PbI precursor solution.
View Article and Find Full Text PDFACS Omega
September 2025
Institut de Chimie et Procédés pour l'Energie, l'Environnement et la Santé (ICPEES), UMR-7515 CNRS-Université de Strasbourg, 25 rue Becquerel, 67087 Strasbourg, France.
For photodetection applications using 3D hybrid perovskites (HPs), dense and thick films or compacted powders in wafer form are needed and generally require large amounts of HPs. HPs are also often combined with a graphene/carbon layer to improve their conductivity. Among HP synthesis methods, mechanosynthesis, a green synthesis method, provides a large amount of powders, which are furthermore easily densified in compact wafers due to their mechanical activation.
View Article and Find Full Text PDFAdv Sci (Weinh)
September 2025
Material Science and Engineering Program (MSE), Physical Sciences and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Kingdom of Saudi Arabia.
In conventional semiconductors, electrical and thermal conductivity are typically coupled, posing a challenge in optimizing both simultaneously. Overcoming this inherent trade-off enables strategies for advancing electronic applications. Herein, a strategy is demonstrated to decouple electrical and thermal conductivity trade-off by creating heterostructures of highly conductive single-walled carbon nanotubes (SWCNTs) coated with low conductivity hybrid perovskites.
View Article and Find Full Text PDFAdv Mater
September 2025
School of Electrical Engineering, Korea University, Seoul, 02841, Republic of Korea.
Neuromorphic computing addresses the von Neumann bottleneck by integrating memory and processing to emulate synaptic behavior. Artificial synapses enable this functionality through analog conductance modulation, low-power operation, and nanoscale integration. Halide perovskites with high ionic mobilities and solution processabilities have emerged as promising materials for such devices; however, inherent stochastic ion migration and thermal instability lead to asymmetric and nonlinear characteristics, ultimately impairing their learning and inference capabilities.
View Article and Find Full Text PDFNat Commun
August 2025
School of Physics and Technology, Key Lab of Artificial Micro- and Nano-Structures of Ministry of Education, School of Microelectronics, Wuhan University, Wuhan, China.
All-perovskite tandem solar cells offer great promise for achieving low levelized cost of electricity, but their performance remains limited by insufficient near-infrared photon absorption in narrow bandgap tin-lead (Sn-Pb) subcells. Micron-thick Sn-Pb layers are essential for maximizing absorption, yet high-concentration precursor solutions often cause non-uniform crystallization, stoichiometric imbalance and limited carrier diffusion lengths. Here we identify the root cause of these limitations as the insufficient coordination of tin(II) iodide (SnI) in conventional dimethylformamide (DMF)/dimethyl sulfoxide (DMSO) binary solvent system at high precursor concentrations, resulting in Sn-rich colloids that nucleate detrimental Sn-rich phases in final films.
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