Spectroscopy — Carbon quantum dot-mediated binary metal-organic framework nanosheets for efficient oxygen evolution at ampere-level current densities in proton exchange membrane electrolyzers

3 measurement groups · 11 results

Reported values remain attached to the sample, method, conditions, extraction quality and source location that produced them.

In situ FT-IR spectroscopy

Infrared spectroscopy

NiFe-MOF-CQD on glassy carbon electrode · Electrode

In situ infrared in 1.0 M KOH at 1.50 V vs RHE; H-type divided cell with Nafion 117; Ag/AgCl reference and graphite counter; spectra captured every 30 s for 30 min.

Geometry: catalyst on gas diffusion layer/carbon paper circle, 0.6 cm diameter, on ATR silicon prism
Context: target composite compared with pristine NiFe-MOF under OER conditions
Measurement source: S3 · The measurement of In-situ infrared spectroscopy · Figure 4g,h

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
*NiFe-MOF-CQD in situ FTIR OOH/O2- band**	1224 cm-1	—	—	Text Exact Reported	31258 · Results and discussion · Figure 4h
*NiFe-MOF in situ FTIR OOH band**	1220 cm-1	—	—	Text Exact Reported	31258 · Results and discussion · Figure 4g
Weakly adsorbed molecular oxygen O-O band	around 1406 cm-1	—	—	Text Approximate	31258 · Results and discussion · Figure 4h

In situ Raman spectroscopy

Raman spectroscopy

NiFe-MOF-CQD on glassy carbon electrode · Electrode

In situ Raman in flow cell with 1.0 M KOH; GDL working electrode, Ag/AgCl reference, Pt wire counter; 532 nm laser, 50x objective; measured at 1.5 V vs RHE.

Geometry: GDL electrode in flow cell
Context: target composite under OER conditions
Measurement source: S4 · The measurement of In-situ Raman spectroscopy · Figure 4f

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
In situ Raman OER-induced peaks	near 496 and 588 cm-1 at 1.5 V vs RHE	—	—	Text Approximate	31258 · Results and discussion · Figure 4f

Raman, FT-IR and XPS spectroscopy

Infrared spectroscopy Raman spectroscopy X-ray photoelectron spectroscopy

NiFe-MOF-CQD · Nanosheet

Spectroscopic confirmation of NiFe-MOF-CQD composition, bonding and electronic-state shifts.

Context: target composite compared with pristine NiFe-MOF and CQD
Measurement source: S1-S2 · Materials Characterization · Figures 3, S4, S6, S7

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
CQD FT-IR C-F/C-F2 peaks	1124 and 824 cm-1	—	—	Text Exact Reported	31256 · Results and discussion · Figure S4c
NiFe-MOF/NiFe-MOF-CQD FT-IR coordination bands	1620, 1396, 740 and 594 cm-1	—	—	Text Exact Reported	31256 · Results and discussion · Figure 3c
NiFe-MOF/NiFe-MOF-CQD Raman bands	1092, 1386 and 1612 cm-1	—	—	Text Rounded Reported	31255 · Results and discussion · Figure 3b
C 1s deconvoluted peaks	284.8, 286.1 and 288.4 eV	—	—	Text Exact Reported	31257 · Results and discussion · Figure S7b
Fe 2p peak shifts after CQD coupling	0.66 eV and 0.31 eV toward lower binding energies	—	—	Text Exact Reported	31257 · Results and discussion · Figure 3f
Ni 2p peaks	855.6 and 873.2 eV	—	—	Text Exact Reported	31257 · Results and discussion · Figure 3e
O 1s deconvoluted peaks	532.68, 531.06 and 529.13 eV	—	—	Text Exact Reported	31257 · Results and discussion · Figure 3d