Electrochemistry Application — Nanocubic bimetallic organic framework self-templated from Ni precursor as efficient electrocatalysts for oxygen evolution reaction

9 measurement groups · 27 results

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

Cyclic voltammetry double-layer capacitance / ECSA proxy

Voltammetry

Ni NCs@MIL-53(NiFe), optimised Ni NCs:FeCl2 mass ratio 3 · Powder

CV curves in non-redox potential range; Delta j versus scan rate at 1.07 V vs RHE; slope 2Cdl used to represent ECSA.

Temperature: room temperature
Geometry: RDE catalyst films
Context: target sample with control values in comparison group
Measurement source: 11713 · Electrochemical property and characterization · Fig. 5a-c, Fig. S8

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
ECSA proxy 2Cdl	0.114 (figure label; unit follows Fig. 5 caption/text ambiguity)	—	—	Figure Axis Rounded Reported	11713 · Electrochemical property and characterization · Fig. 5c
ECSA proxy 2Cdl	0.130 (figure label; unit follows Fig. 5 caption/text ambiguity)	—	—	Figure Axis Rounded Reported	11713 · Electrochemical property and characterization · Fig. 5c
ECSA proxy 2CdlMarked as a best value within this paper	0.174 F cm^-2	—	—	Text Exact Reported	11713 · Electrochemical property and characterization · Fig. 5b,c

Electrochemical impedance spectroscopy (Nyquist plot)

Impedance spectroscopy

Ni NCs@MIL-53(NiFe), optimised Ni NCs:FeCl2 mass ratio 3 · Powder

Three-electrode EIS in 1 M KOH; frequency range 100 kHz to 100 mHz, 5 mV modulation at 1.55 V vs RHE without iR drops.

Temperature: room temperature
Geometry: RDE catalyst films
Context: target sample with control values in comparison group
Measurement source: 11707 · Electrochemical characterizations · Fig. 5d

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Charge-transfer resistance comparisonMarked as a best value within this paper	Ni NCs@MIL-53(NiFe) semicircle radius much lower than Ni NCs and MIL-53(Fe)	—	—	Qualitative Qualitative	11713 · Electrochemical property and characterization · Fig. 5d

Linear sweep voltammetry (OER polarisation)

Voltammetry

MIL-53(Fe) · Powder

Same RDE OER conditions as target: 1 M KOH, 1600 rpm, 5 mV s^-1, iR-corrected, catalyst loading 0.2 mg cm^-2.

Temperature: room temperature
Geometry: 4 mm glassy-carbon rotating disk electrode; 0.1256 cm2
Context: pristine MOF control
Measurement source: 11711 · Electrochemical property and characterization · Fig. 4a,c,d

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Current density at eta = 388 mV	1.18 mA cm^-2	—	—	Text Exact Reported	11711 · Electrochemical property and characterization · Fig. 4d
Overpotential at 20 mA cm^-2	579 mV	—	—	Text Exact Reported	11711 · Electrochemical property and characterization · Fig. 4c

Linear sweep voltammetry (OER polarisation)

Voltammetry

Ni NCs · Powder

Same RDE OER conditions as target: 1 M KOH, 1600 rpm, 5 mV s^-1, iR-corrected, catalyst loading 0.2 mg cm^-2.

Temperature: room temperature
Geometry: 4 mm glassy-carbon rotating disk electrode; 0.1256 cm2
Context: Ni NC precursor/control
Measurement source: 11711 · Electrochemical property and characterization · Fig. 4a,c,d

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Current density at eta = 388 mV	18 mA cm^-2	—	—	Text Exact Reported	11711 · Electrochemical property and characterization · Fig. 4d
Overpotential at 20 mA cm^-2	456 mV	—	—	Text Exact Reported	11711 · Electrochemical property and characterization · Fig. 4c
Ni2+/Ni3+ oxidation peak potential	about 1.5 V vs RHE	—	—	Text Approximate	11711 · Electrochemical property and characterization · Fig. 4a

Linear sweep voltammetry (OER polarisation)

Voltammetry

Ni NCs@MIL-53(NiFe), optimised Ni NCs:FeCl2 mass ratio 3 · Powder

Three-electrode RDE in 1 M KOH; glassy-carbon RDE working electrode, Pt wire auxiliary, Ag/AgCl reference; 1600 rpm, 5 mV s^-1, iR-corrected, catalyst loading 0.2 mg cm^-2.

Temperature: room temperature
Geometry: 4 mm glassy-carbon rotating disk electrode; 0.1256 cm2
Context: target mixed-metal/composite MOF
Measurement source: 11707 · Electrochemical characterizations · Fig. 4a,c,d

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Current density at eta = 388 mVMarked as a best value within this paper	100 mA cm^-2	—	—	Text Exact Reported	11711 · Electrochemical property and characterization · Fig. 4d
Overpotential at 100 mA cm^-2Marked as a best value within this paper	388 mV	—	—	Text Exact Reported	11711 · Electrochemical property and characterization · Fig. 4d
Overpotential at 20 mA cm^-2Marked as a best value within this paper	271 mV	—	—	Text Exact Reported	11711 · Electrochemical property and characterization · Fig. 4c
Overpotential at 20 mA cm^-2 reported in SI Table S1Marked as a best value within this paper	271@20 mA cm^-2	—	—	SI Table Exact Reported	7/8 · Supporting Information · Table S1
Ni2+/Ni3+ oxidation peak potential	around 1.45 V vs RHE	—	—	Text Approximate	11711 · Electrochemical property and characterization · Fig. 4a

Mass activity and turnover frequency calculations

Ni NCs@MIL-53(NiFe), optimised Ni NCs:FeCl2 mass ratio 3 · Powder

Calculated at eta = 0.388 V from current density and catalyst loading m = 0.2 mg cm^-2; TOF assumes all metal atoms involved.

Temperature: room temperature
Geometry: RDE catalyst films
Context: target sample with control values in comparison group
Measurement source: 11707 · Calculation · Eq. 2, Eq. 3, Fig. 4e,f

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Mass activity at eta = 388 mV	5.93 A g^-1	—	—	Text Exact Reported	11712 · Electrochemical property and characterization · Fig. 4e
Mass activity at eta = 388 mV	89.9 A g^-1	—	—	Text Exact Reported	11712 · Electrochemical property and characterization · Fig. 4e
Mass activity at eta = 388 mVMarked as a best value within this paper	502.5 A g^-1	—	—	Text Exact Reported	11712 · Electrochemical property and characterization · Fig. 4e
Turnover frequency at eta = 388 mV	0.0012 s^-1	—	—	Text Exact Reported	11712 · Electrochemical property and characterization · Fig. 4f
Turnover frequency at eta = 388 mV	0.038 s^-1	—	—	Text Exact Reported	11712 · Electrochemical property and characterization · Fig. 4f
Turnover frequency at eta = 388 mVMarked as a best value within this paper	0.269 s^-1	—	—	Text Exact Reported	11712 · Electrochemical property and characterization · Fig. 4f

Tafel analysis from LSV curves

Voltammetry Tafel and polarisation analysis

Ni NCs@MIL-53(NiFe), optimised Ni NCs:FeCl2 mass ratio 3 · Powder

Tafel plots based on eta = b log j + a, extracted from LSV curves for target and controls.

Temperature: room temperature
Geometry: RDE catalyst films
Context: target sample with control values in comparison group
Measurement source: 11711 · Electrochemical property and characterization · Fig. 4b

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Tafel slope	0.819 V dec^-1	819 mV dec^-1	—	Text Exact Reported	11711 · Electrochemical property and characterization · Fig. 4b
Tafel slope	0.768 V dec^-1	768 mV dec^-1	—	Text Exact Reported	11711 · Electrochemical property and characterization · Fig. 4b
Tafel slopeMarked as a best value within this paper	0.226 V dec^-1	226 mV dec^-1	—	Text Exact Reported	11711 · Electrochemical property and characterization · Fig. 4b
Tafel slope reported in SI Table S1Marked as a best value within this paper	144 mV dec^-1	144 mV dec^-1	—	SI Table Exact Reported	7/8 · Supporting Information · Table S1

OER polarisation comparison across Ni NCs:FeCl2 mass ratios

Ni NCs@MIL-53(NiFe) mass-ratio optimisation series · Powder

Polarisation curves and SEM morphology for mass ratios 0.5, 1, 2, 3 and 4.

Geometry: RDE catalyst films for electrochemistry
Context: target optimisation series
Measurement source: 3/8 · Supporting Information · Fig. S2, Fig. S3

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Optimal Ni NCs:FeCl2 mass ratioMarked as a best value within this paper	3	—	—	Text Exact Reported	11707-11708 · Morphology and structure characterization · Fig. S2, Fig. S3

OER durability by CV cycling and chronoamperometry

Voltammetry Chronoamperometry

Ni NCs@MIL-53(NiFe), optimised Ni NCs:FeCl2 mass ratio 3 · Powder

LSV before/after 1000 CV cycles in 1 M KOH; chronoamperometry at ascending current densities 5, 10 and 20 mA cm^-2.

Temperature: room temperature
Geometry: RDE catalyst film
Context: target mixed-metal/composite MOF
Measurement source: 11707 and 11714 · Electrochemical characterizations; Electrochemical property and characterization · Fig. 5e,f

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Chronoamperometry stability	maintained current density for 12000 s with negligible decay at 5, 10, and 20 mA cm^-2	—	—	Text Qualitative	11714 · Electrochemical property and characterization · Fig. 5f
LSV after CV cycling	almost no change after 1000 CV cycles	—	—	Text Qualitative	11714 · Electrochemical property and characterization · Fig. 5e