Bismuth Stabilizes the α-Phase of Formamidinium Lead Iodide Perovskite Single Crystals
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
α-FAPbI3 (FA = formamidinium) perovskite offers an optimal bandgap for single-junction solar cells but converts into a more thermodynamically stable photoinactive δ-polymorph at room temperature. FA- or I-site substitutional alloying stabilizes α-FAPbI3; however, it leads to compositional segregation in operational devices. Here, we stabilize α-FAPbI3 single crystals through Pb-site doping with a heterovalent metal–bismuth (Bi). We show that undoped α-FAPbI3 has an α- to δ-phase half-life transition of <0.15 h, while the optimum concentration of Bi extends it by 4 orders of magnitude. Differential scanning calorimetry (DSC) reveals that Bi has effectively decreased the δ- to α-phase onset transition temperature. Density functional theory (DFT) calculations suggest a relatively clean gap, supporting previous findings on the improved photovoltaic performance of Bi-doped α-FAPbI3-based solar cells.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it