Low-dose (S)TEM elemental analysis of water and oxygen uptake in beam sensitive materials
Bibliographic record
Abstract
The performance stability of organic photovoltaics (OPVs) is largely determined by their nanoscale morphology and composition and is highly dependent on the interaction with oxygen and water from air. Low-dose cryo-(S)TEM techniques, in combination with OPV donor-acceptor model systems, can be used to assess oxygen- and water-uptake in the donor, acceptor and their interface. By determining a materials dependent critical electron dose from the decay of the oxygen K-edge intensity in Electron Energy Loss Spectra, we reliably measured oxygen- and water-uptake minimizing and correcting electron beam effects. With measurements below the dose limit the capability of STEM-EDX, EFTEM and STEM-EELS techniques are compared to qualitatively and quantitatively measure oxygen and water uptake in these OPV model systems. Here we demonstrate that oxygen and water is mainly taken up in acceptor-rich regions, and that specific oxygen uptake at the donor-acceptor interphase does not occur. STEM-EELS is shown to be the best suitable technique, enabling quantification of the local oxygen concentration in OPV model systems.
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How this classification was reachedexpand
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) | 0.000 | 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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".