Solid-Solution Phase Transition Induced by Surface Electrochemico–Mechanical Interactions for High-Voltage Sodium-Layered Oxide Cathodes
Bibliographic record
Abstract
The phase transition behaviors of sodium-layered oxide (SLO) cathodes play an important role in their electrochemical performances at high voltages. Specifically, SLOs experience a phase transition from the P to OP intergrowth phase with Na-deficient O layers, leading to sluggish Na extraction/insertion kinetics, severe strain formation, and high reactive activity with electrolytes. In addition to the normally used phase engineering strategies such as bulk doping, we demonstrate here that a Mn-gradient surface layer can significantly tune the bulk phase transition from the OP intergrowth to O3 solid-solution transition, evidenced by in situ XRD and Cryo-STEM analyses. The Mn-rich surface has asynchronous Na extraction properties compared to the bulk at high voltages, suppressing the nucleation and growth of the OP intergrowth phase as the generated stress cannot be well released while facilitating the formation of a stressless O3 solid-solution phase. Benefiting from the O3 solid-solution phase change behaviors, the SLO with the Mn-rich surface shows much improved electrochemical performances at high voltages up to 4.3 V in terms of energy density, rate performance, energy conversion efficiency, and cycling stability.
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.
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".