Electrochemistry Application — In situ growth of ultrathin Co-MOF nanosheets on Α-Fe2O3 hematite nanorods for efficient photoelectrochemical water oxidation

17 measurement groups · 55 results

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

Bode phase analysis from EIS

Impedance spectroscopy

Fe2O3@Co-MOF varied Co/MIm ratio series · Electrode

Frequency range 100 kHz to 1 Hz; charge-transfer time factor determined from characteristic frequency.

Geometry: photoanode series
Context: Co-modified and Co-MOF samples versus controls
Measurement source: p003 / SI p3 · Supporting information · Fig. S5

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
bare Fe2O3 charge-transfer time factor tau_n	approximately 1.0 ms from SI Fig. S5b	—	—	Figure Axis Approximate	p003 / SI p3 · Supporting information · Fig. S5b
Bode characteristic frequency shift	Fe2O3@0.1Co and Fe2O3@0.1Co@0.8MIm shift to higher frequency versus bare and MIm-modified hematite	—	—	Qualitative Qualitative	p007 / journal p394 · 3 Results and discussion · Fig. S5
charge-transfer time interpretation	charge transfer characteristic time is shortened in Co-modified samples	—	—	Qualitative Qualitative	p007 / journal p394 · 3 Results and discussion · Fig. S5b
Fe2O3@0.1Co@0.8MIm charge-transfer time factor tau_n	approximately 0.85 ms from SI Fig. S5b	—	—	Figure Axis Approximate	p003 / SI p3 · Supporting information · Fig. S5b

Electrochemical impedance spectroscopy (EIS) Nyquist fit

Impedance spectroscopy

bare Fe2O3 · Electrode

Under light irradiation with 0.05 V bias versus Ag/AgCl in 0.5 M KCl, 0.01 M K3[Fe(CN)6], 0.01 M K4[Fe(CN)6]; equivalent circuit fit.

Geometry: three-electrode photoanode
Context: bare Fe2O3
Measurement source: p007 / journal p394 · 3 Results and discussion · Fig. 6a; Table 1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
bare interfacial resistance interpretation	Rct,ss = 107.2 ohm cm2	—	—	Text Exact Reported	p007 / journal p394 · 3 Results and discussion · Fig. 6a; Table 1
Bare Fe2O3 bulk capacitance Cbulk	54.7	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Bare Fe2O3 surface-state capacitance Css	4.8	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Bare Fe2O3 bulk charge-transfer resistance Rct,bulk	55.03	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Bare Fe2O3 surface-state charge-transfer resistance Rct,ss	107.2	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Bare Fe2O3 series resistance Rs	129.8	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1

Electrochemical impedance spectroscopy (EIS) Nyquist fit

Impedance spectroscopy

Fe2O3@0.1Co · Electrode

Under light irradiation with 0.05 V bias versus Ag/AgCl in 0.5 M KCl, 0.01 M K3[Fe(CN)6], 0.01 M K4[Fe(CN)6]; equivalent circuit fit.

Geometry: three-electrode photoanode
Context: Fe2O3@0.1Co
Measurement source: p007 / journal p394 · 3 Results and discussion · Fig. 6a; Table 1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Fe2O3@0.1Co bulk capacitance Cbulk	116.0	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.1Co surface-state capacitance Css	4.8	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.1Co bulk charge-transfer resistance Rct,bulk	65.8	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.1Co surface-state charge-transfer resistance Rct,ss	125.7	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.1Co series resistance Rs	100.2	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1

Electrochemical impedance spectroscopy (EIS) Nyquist fit

Impedance spectroscopy

Fe2O3@0.1Co@0.8MIm · Electrode

Under light irradiation with 0.05 V bias versus Ag/AgCl in 0.5 M KCl, 0.01 M K3[Fe(CN)6], 0.01 M K4[Fe(CN)6]; equivalent circuit fit.

Geometry: three-electrode photoanode
Context: Fe2O3@0.1Co@0.8MIm
Measurement source: p007 / journal p394 · 3 Results and discussion · Fig. 6a; Table 1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
target interfacial resistance interpretationMarked as a best value within this paper	extremely low surface charge transfer resistance, Rct,ss = 13.5 ohm cm2	—	—	Text Exact Reported	p007 / journal p394 · 3 Results and discussion · Fig. 6a; Table 1
Fe2O3@0.1Co@0.8MIm bulk capacitance Cbulk	101.0	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.1Co@0.8MIm surface-state capacitance CssMarked as a best value within this paper	81.5	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.1Co@0.8MIm bulk charge-transfer resistance Rct,bulk	86.1	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.1Co@0.8MIm surface-state charge-transfer resistance Rct,ssMarked as a best value within this paper	13.5	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.1Co@0.8MIm series resistance Rs	90.3	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1

Electrochemical impedance spectroscopy (EIS) Nyquist fit

Impedance spectroscopy

Fe2O3@0.8MIm · Electrode

Under light irradiation with 0.05 V bias versus Ag/AgCl in 0.5 M KCl, 0.01 M K3[Fe(CN)6], 0.01 M K4[Fe(CN)6]; equivalent circuit fit.

Geometry: three-electrode photoanode
Context: Fe2O3@0.8MIm
Measurement source: p007 / journal p394 · 3 Results and discussion · Fig. 6a; Table 1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Fe2O3@0.8MIm bulk capacitance Cbulk	36.7	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.8MIm surface-state capacitance Css	6.9	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.8MIm bulk charge-transfer resistance Rct,bulk	46.4	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.8MIm surface-state charge-transfer resistance Rct,ss	117.9	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1
Fe2O3@0.8MIm series resistance Rs	106.6	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1

IPCE spectroscopy

Photoresponse and photoelectrochemistry

bare Fe2O3 · Electrode

IPCE measured with xenon light source and monochromator from 369 to 730 nm at 1.23 V_RHE for pristine hematite control.

Geometry: photoanode
Context: bare hematite pristine control
Measurement source: p003 / journal p390 · 2.3 Photoelectrochemical measurements

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
bare hematite IPCE at 400 nm	6.8% at 400 nm and 1.23 V_RHE	—	—	Text Exact Reported	p005 / journal p392 · 3 Results and discussion · Fig. 3b

IPCE spectroscopy

Photoresponse and photoelectrochemistry

Fe2O3@0.1Co@0.8MIm · Electrode

IPCE measured with xenon light source and monochromator from 369 to 730 nm at 1.23 V_RHE.

Geometry: photoanode
Context: target compared with bare hematite
Measurement source: p003 / journal p390 · 2.3 Photoelectrochemical measurements

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
target IPCE at 400 nmMarked as a best value within this paper	13.1% at 400 nm and 1.23 V_RHE	—	—	Text Exact Reported	p005 / journal p392 · 3 Results and discussion · Fig. 3b
long-wavelength IPCE	IPCE decreased sharply to nearly zero above 600 nm	—	—	Text Approximate	p005 / journal p392 · 3 Results and discussion · Fig. 3b

photoelectrochemical J-V / linear sweep

Photoresponse and photoelectrochemistry

bare Fe2O3 · Electrode

Three-electrode PEC in 1.0 M NaOH (pH 13.6), Ag/AgCl reference, Pt counter, 300 W xenon lamp, 100 mW cm^-2; dark and illuminated curves.

Geometry: photoanode working electrode
Context: pristine control
Measurement source: p002 / journal p389 · 2.3 Photoelectrochemical measurements

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
photocurrent onset potential	0.82 V_RHE	—	—	Text Exact Reported	p005 / journal p392 · 3 Results and discussion · Fig. 3a
photocurrent density at 1.23 V_RHE	0.71 mA cm^-2 at +1.23 V_RHE	—	—	Text Exact Reported	p005 / journal p392 · 3 Results and discussion · Fig. 3a

photoelectrochemical J-V / linear sweep

Photoresponse and photoelectrochemistry

Fe2O3@0.1Co · Electrode

Same PEC conditions as bare Fe2O3; Co-only surface modified control.

Geometry: photoanode working electrode
Context: Co-only control
Measurement source: p005 / journal p392 · 3 Results and discussion · Fig. 3

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Co(II) oxidation peak	obvious peak about 1.2 V_RHE, also in dark	—	—	Text Approximate	p005 / journal p392 · 3 Results and discussion · Fig. 3a
Co-only cathodic onset shift	260 mV cathodic shift relative to bare alpha-Fe2O3	—	—	Text Exact Reported	p005 / journal p392 · 3 Results and discussion · Fig. 3a

photoelectrochemical J-V / linear sweep

Photoresponse and photoelectrochemistry

Fe2O3@0.8MIm · Electrode

Same PEC conditions as bare Fe2O3; linker-only control.

Geometry: photoanode working electrode
Context: MIm-only control
Measurement source: p005 / journal p392 · 3 Results and discussion · Fig. 3

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
MIm-only J-V effect	resembled bare hematite photoanodes very closely	—	—	Qualitative Qualitative	p005 / journal p392 · 3 Results and discussion · Fig. 3a

photoelectrochemical J-V / linear sweep

Photoresponse and photoelectrochemistry

Fe2O3@Co-MOF varied Co/MIm ratio series · Electrode

J-V curves for varied Co/MIm ratios in dark and under illumination.

Geometry: photoanode working electrodes
Context: Co-MOF ratio optimisation
Measurement source: p006 / journal p393 · 3 Results and discussion · Fig. 5

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Fe2O3@0.05Co@0.4MIm photocurrent density at 1.23 V_RHE	approximately 1.7 mA cm^-2	—	—	Figure Axis Approximate	p006 / journal p393 · 3 Results and discussion · Fig. 5
Fe2O3@0.05Co@0.8MIm photocurrent density at 1.23 V_RHE	approximately 1.6 mA cm^-2	—	—	Figure Axis Approximate	p006 / journal p393 · 3 Results and discussion · Fig. 5
Fe2O3@0.1Co@0.4MIm photocurrent density at 1.23 V_RHE	approximately 1.4 mA cm^-2	—	—	Figure Axis Approximate	p006 / journal p393 · 3 Results and discussion · Fig. 5
Fe2O3@0.1Co@0.8MIm photocurrent density at 1.23 V_RHEMarked as a best value within this paper	approximately 2.0 mA cm^-2	—	—	Figure Axis Approximate	p006 / journal p393 · 3 Results and discussion · Fig. 5
Fe2O3@0.1Co@1.6MIm photocurrent density at 1.23 V_RHE	approximately 1.9 mA cm^-2	—	—	Figure Axis Approximate	p006 / journal p393 · 3 Results and discussion · Fig. 5
Fe2O3@0.2Co@0.8MIm photocurrent density at 1.23 V_RHE	approximately 1.4 mA cm^-2	—	—	Figure Axis Approximate	p006 / journal p393 · 3 Results and discussion · Fig. 5
Fe2O3@0.2Co@1.6MIm photocurrent density at 1.23 V_RHE	approximately 1.3 mA cm^-2	—	—	Figure Axis Approximate	p006 / journal p393 · 3 Results and discussion · Fig. 5
Fe2O3@0.3Co@2.4MIm photocurrent density at 1.23 V_RHE	approximately 1.1 mA cm^-2	—	—	Figure Axis Approximate	p006 / journal p393 · 3 Results and discussion · Fig. 5
best Co/MIm ratioMarked as a best value within this paper	Fe2O3@0.1Co@0.8MIm exhibited best PEC performance in working voltage range	—	—	Qualitative Qualitative	p006 / journal p393 · 3 Results and discussion · Fig. 5a

photoelectrochemical J-V / linear sweep

Photoresponse and photoelectrochemistry

Fe2O3@0.1Co@0.8MIm · Electrode

Same PEC conditions; optimised Co-MOF nanosheet-modified hematite.

Geometry: photoanode working electrode
Context: target composite versus pristine and precursor controls
Measurement source: p005 / journal p392 · 3 Results and discussion · Fig. 3

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
photocurrent improvement versus bareMarked as a best value within this paper	200% improvement	—	—	Text Exact Reported	p001 / journal p388 · Abstract
photocurrent onset potentialMarked as a best value within this paper	0.64 V_RHE	—	—	Text Exact Reported	p005 / journal p392 · 3 Results and discussion · Fig. 3a
photocurrent density at 1.23 V_RHEMarked as a best value within this paper	2.0 mA cm^-2 at 1.23 V_RHE	—	—	Text Exact Reported	p005 / journal p392 · 3 Results and discussion · Fig. 3a
Co redox peak suppression	Co 2+/3+ oxidation peaks greatly suppressed in dark and illumination	—	—	Qualitative Qualitative	p005 / journal p392 · 3 Results and discussion · Fig. 3a
cathodic onset shift versus bareMarked as a best value within this paper	180 mV	—	—	Text Exact Reported	p001 / journal p388 · Abstract

Mott-Schottky analysis

bare Fe2O3 · Electrode

Mott-Schottky measurements at 1 kHz under dark conditions; carrier density estimated from slopes.

Atmosphere: dark
Geometry: three-electrode photoanode
Context: bare Fe2O3
Measurement source: p007 / journal p394 · 3 Results and discussion · Fig. 6b; Table 1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
bare electron density	Nd = 6.2 * 10^19 cm^-3	—	—	Text Exact Reported	p007 / journal p394 · 3 Results and discussion · Fig. 6b
Bare Fe2O3 donor/electron density Nd	6.2e+19 cm^-3	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1

Mott-Schottky analysis

Fe2O3@0.1Co · Electrode

Mott-Schottky measurements at 1 kHz under dark conditions; carrier density estimated from slopes.

Atmosphere: dark
Geometry: three-electrode photoanode
Context: Fe2O3@0.1Co
Measurement source: p007 / journal p394 · 3 Results and discussion · Fig. 6b; Table 1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Fe2O3@0.1Co donor/electron density Nd	5.9e+19 cm^-3	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1

Mott-Schottky analysis

Fe2O3@0.1Co@0.8MIm · Electrode

Mott-Schottky measurements at 1 kHz under dark conditions; carrier density estimated from slopes.

Atmosphere: dark
Geometry: three-electrode photoanode
Context: Fe2O3@0.1Co@0.8MIm
Measurement source: p007 / journal p394 · 3 Results and discussion · Fig. 6b; Table 1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
target electron densityMarked as a best value within this paper	Nd = 1 * 10^20 cm^-3	—	—	Text Exact Reported	p007 / journal p394 · 3 Results and discussion · Fig. 6b
Fe2O3@0.1Co@0.8MIm donor/electron density NdMarked as a best value within this paper	1.0e+20 cm^-3	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1

Mott-Schottky analysis

Fe2O3@0.8MIm · Electrode

Mott-Schottky measurements at 1 kHz under dark conditions; carrier density estimated from slopes.

Atmosphere: dark
Geometry: three-electrode photoanode
Context: Fe2O3@0.8MIm
Measurement source: p007 / journal p394 · 3 Results and discussion · Fig. 6b; Table 1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Fe2O3@0.8MIm donor/electron density Nd	6.9e+19 cm^-3	—	—	Table Exact Reported	p007 / journal p394 · 3 Results and discussion · Table 1

Mott-Schottky analysis

Fe2O3@Co-MOF varied Co/MIm ratio series · Electrode

Supplemental Mott-Schottky plots of bare alpha-Fe2O3 and surface-modified alpha-Fe2O3 films with varied Co/MIm ratios.

Atmosphere: dark
Geometry: three-electrode photoanode
Context: surface-modified alpha-Fe2O3 ratio series
Measurement source: p004 / SI p4 · Supporting information · Fig. S6

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
supplemental Mott-Schottky ratio-series trend	surface-modified Fe2O3 films show ratio-dependent Mott-Schottky curves with slope changes near high potential	—	—	Visual Estimate Qualitative	p004 / SI p4 · Supporting information · Fig. S6