Variation of the MnO<sub>2</sub> Birnessite Structure upon Charge/Discharge in an Electrochemical Supercapacitor Electrode in Aqueous Na<sub>2</sub>SO<sub>4</sub> Electrolyte
Bibliographic record
Abstract
This paper provides new insight on the charge storage mechanism in crystallized Mg-doped sodium birnessite-type manganese dioxide used as active supercapacitor electrode material that involves the intercalation/deintercalation of cations between the sheets during electrochemical reduction/oxidation, respectively. An increase of the interlayer spacing from 0.710 to 0.720 nm upon electrochemical oxidation in the presence of Na + cations in the electrolyte is associated with the deintercalation of Na + and the intercalation of H 2 O between the layers. A progressive crystallinity loss of the material is also observed upon potential cycling between the oxidized and reduced states. Despite these structural changes, the birnessite electrode exhibits a stable capacitance of 145 F/g over 1100 cycles.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| 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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), 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".