Integrity review of 'Enhancing Oxygen Reduction Kinetics and Proton Transfer of La0.6Sr0.4Co0.2Fe0.8O3-δ Cathode through Pr2Ni0.5Co0.5O4-δ Impregnation for Protonic Ceramic Fuel Cells' (Adv. Energy Mater., 2024)

Verdict

🟠 Highly suspicious. Two confirmed, high-severity issues (physically impossible Ro vs. temperature trend; incorrect stoichiometry in the DFT supercell) are accompanied by clerical errors and visual anomalies that warrant editorial and institutional investigation.

Key findings

• Physically impossible ohmic resistance (Ro) trend in the PNC-LSCF single cell across 700 → 650 → 600 → 550°C: 0.07 → 0.01 → 0.12 → 0.15 Ω cm². The 700 → 650°C drop from 0.07 to 0.01 Ω cm² violates the expected monotonic increase of electrolyte ohmic resistance with decreasing temperature (Arrhenius-type behavior).
• Incorrect chemical formula in the DFT model: Pr4Ni2CoO12 is built to represent PrNi0.5Co0.5O3-δ (PNC). A 4× supercell of PrNi0.5Co0.5O3 should be Pr4Ni2Co2O12; the missing Co atom changes the stoichiometry to PrNi0.5Co0.25O3, so the computed oxygen-vacancy formation energies and proton-transfer barriers do not correspond to the claimed material.
• Suspiciously smooth 200-hour stability curve (Figure 1h) and an unusually perfect linear Arrhenius fit of surface exchange coefficients k (Figure 2f), with no visible scatter or error bars; flagged as visual anomaly only, since raw data files were not available.
• Possible channel duplication/similarity between Pr and O EDX maps in Figure 3d (TEM-EDS mapping of PNC-LSCF); flagged as visual anomaly only, without pixel-level evidence.
• Multiple clerical and unit errors in the main text: the 200-h stability test is described as performed 'under a constant current of 800 mAh cm⁻² at 700°C' (mAh is a capacity unit, not a current) and the Rp of PNC-LSCF at 550°C is reported as '0.1.35 Ω cm²' (likely intended as 1.35 Ω cm²).

Evidence highlights

• Exact text quoted from the paper: 'The Ro of PNC-LSCF in the single cell is 0.07, 0.01, 0.12, and 0.15 Ω cm² at 700, 650, 600, and 550°C, respectively.'
• Exact text quoted from the paper: 'the orthorhombic structure of Pr4Ni2CoO12 and La2Sr2Co2Fe2O12 are constructed to represent PNC and LSCF'.
• Exact text quoted from the paper: '...under a constant current of 800 mAh cm⁻² at 700°C.'
• Exact text quoted from the paper: '...decrease to 0.06, 0.14, 0.362, and 0.1.35 Ω cm² at 700, 650, 600, and 550°C, respectively.'
• Manuscript metadata: Received July 29, 2024; published online October 21, 2024; DOI 10.1002/aenm.202403335; journal Advanced Energy Materials.

Notes

• Confirmed findings (Ro trend and DFT stoichiometry) are internally verifiable directly from the published text and do not depend on access to raw data.
• Image-based concerns (Figure 1h smoothness, Figure 2f fit, Figure 3d Pr/O map similarity) are visual anomalies only and would require the original raw data, original .tiff micrographs, and higher-resolution figures to confirm; these are marked as 'insufficient evidence' in the source report.
• The clerical errors ('mAh cm⁻²', '0.1.35 Ω cm²') are low-severity on their own but, taken together with the two confirmed issues, suggest a generally careless approach to data handling and reporting.
• Recommended follow-up: request raw EIS/impedance files, the DFT .cif/cif-like structural files, and original TEM .tiff images from the corresponding author; raise concerns via PubPeer and notify the journal editorial office; cross-check related references (e.g., refs. 28, 46, 56) for possible data reuse or duplicate publication.
• This is an AI-assisted assessment for academic discussion only; final determination of misconduct requires an institutional or publisher investigation.