Electrochemistry Application — Split-cell symmetric supercapacitor performance of bimetallic MOFs yolk-shell hierarchical microstructure

7 measurement groups · 35 results

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

Cyclic voltammetry (CV), scan-rate series

Voltammetry

Ni-Zn MOF//Ni-Zn MOF split-cell symmetric device (SC-SD) · Electrode

SC-SD CV profiles at a stated 1.6 V figure-caption potential window across scan rates; SI gives 10-400 mV s-1, while Fig. 3b legend also includes 500 mV s-1.

Geometry: Split-cell symmetric device, Ni-Zn MOF//Ni-Zn MOF
Context: device using composite electrodes
Measurement source: 4 · Results and discussion · Fig. 3b

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Maximum CV scan rate visible in legend	500 mV s-1	—	—	Figure Axis Exact Reported	4 · Figure legend · Fig. 3b
Maximum CV scan rate discussed in text	400 mV s-1	—	—	Text Exact Reported	4 · Results and discussion · Fig. 3b
Minimum CV scan rate	10 mV s-1	—	—	Text Exact Reported	4 · Results and discussion · Fig. 3b
CV shape retention with scan rate	Shape of the CV profile was maintained with increasing scan rate, indicating high rate capacity	—	—	Text Qualitative	4 · Results and discussion · Fig. 3b

Cyclic voltammetry (CV), potential-window evaluation

Voltammetry

Ni-Zn MOF//Ni-Zn MOF split-cell symmetric device (SC-SD) · Electrode

CV profiles at different potential windows; Fig. 3a scan rate 50 mV s-1; SI says CV tests at 10-400 mV s-1 and 0-2 V on a Biologic SP-200.

Geometry: Split-cell symmetric device, Ni-Zn MOF//Ni-Zn MOF
Context: device using composite electrodes
Measurement source: 1.3 Electrochemical measurements · Fig. 3a

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Maximum CV potential-window upper limit tested	2.0 V	—	—	Text Exact Reported	4 · Results and discussion · Fig. 3a
Minimum CV potential-window upper limit tested	0.4 V	—	—	Figure Axis Exact Reported	4 · Results and discussion · Fig. 3a

Cycling stability test

Ni-Zn MOF//Ni-Zn MOF split-cell symmetric device (SC-SD) · Electrode

SC-SD cycling over 2000 cycles at 8 A g-1

Geometry: Split-cell symmetric device, Ni-Zn MOF//Ni-Zn MOF
Context: device using composite electrodes
Measurement source: 5 · Results and discussion; Conclusion · Fig. 4b

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Capacity retention after cyclingMarked as a best value within this paper	90.05%	—	—	Text Exact Reported	5 · Conclusion · Fig. 4b
Coulombic efficiency during cycling	approximately 100%	—	—	Figure Axis Approximate	5 · Figure axis · Fig. 4b
Cycling-test current density	8 A g-1	—	—	Text Exact Reported	5 · Results and discussion · Fig. 4b
Cycling-test duration	2000 cycles	—	—	Text Exact Reported	5 · Results and discussion · Fig. 4b

Electrochemical impedance spectroscopy (EIS)

Impedance spectroscopy

Ni-Zn MOF//Ni-Zn MOF split-cell symmetric device (SC-SD) · Electrode

Nyquist plot with equivalent circuit for SC-SD; SI states EIS was used to assess electrochemical activity on a Biologic SP-200.

Geometry: Split-cell symmetric device, Ni-Zn MOF//Ni-Zn MOF
Context: device using composite electrodes
Measurement source: 4-5 · Results and discussion · Fig. 4a

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Device electrical-conductivity assessment	Appropriate electrical conductivity inferred from low diffusion impedance	—	—	Text Qualitative	5 · Results and discussion · Fig. 4a
Charge-transfer resistanceMarked as a best value within this paper	2.5 ohm	—	—	Text Exact Reported	4-5 · Results and discussion · Fig. 4a

Electrochemical workstation and device-test protocol

Ni-Zn MOF//Ni-Zn MOF split-cell symmetric device (SC-SD) · Electrode

All electrochemical measurements performed on Biologic SP-200; standard split-cell symmetric device with two 12 mm Ni-Zn MOF electrodes, filter-paper separator and PVA/KOH gel electrolyte.

Geometry: Split-cell symmetric device, Ni-Zn MOF//Ni-Zn MOF
Context: device using composite carbon-fabric electrodes
Measurement source: 1.3 Electrochemical measurements

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Active material mass per electrode slurry	2.5 mg	—	—	Text Exact Reported	1.3 Electrochemical measurements
Carbon-fabric electrode diameter	12 mm	—	—	Text Exact Reported	1.3 Electrochemical measurements
Carbon-fabric electrode thickness	0.3 mm	—	—	Text Exact Reported	1.3 Electrochemical measurements
KOH mass for gel electrolyte	3 g KOH	—	—	Text Exact Reported	1.4 Preparation of PVA/KOH gel electrolyte
PVA mass for gel electrolyte	3 g PVA	—	—	Text Exact Reported	1.4 Preparation of PVA/KOH gel electrolyte

Galvanostatic charge-discharge (GCD) and specific capacitance calculation

Galvanostatic cycling

Ni-Zn MOF//Ni-Zn MOF split-cell symmetric device (SC-SD) · Electrode

GCD profiles and specific capacitance versus current density for SC-SD; SI reports 6.0 M PVA/KOH electrolyte and 0-1.5 V GCD range on a Biologic SP-200.

Geometry: Split-cell symmetric device, Ni-Zn MOF//Ni-Zn MOF
Context: device using composite electrodes
Measurement source: 1.3 Electrochemical measurements · Fig. 3c-d

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Specific capacitance at 1.1 A g-1Marked as a best value within this paper	88.66 F g-1	—	—	Text Exact Reported	4 · Results and discussion · Fig. 3d
Specific capacitance at 2.2 A g-1	approximately 71 F g-1	—	—	Figure Axis Approximate	4 · Figure axis · Fig. 3d
Specific capacitance at 3.3 A g-1	approximately 62 F g-1	—	—	Figure Axis Approximate	4 · Figure axis · Fig. 3d
Specific capacitance at 4.4 A g-1	approximately 52 F g-1	—	—	Figure Axis Approximate	4 · Figure axis · Fig. 3d
Specific capacitance at 6.6 A g-1	approximately 22 F g-1	—	—	Figure Axis Approximate	4 · Figure axis · Fig. 3d
Maximum GCD current density	6.6 A g-1	—	—	Figure Axis Exact Reported	4 · Figure legend · Fig. 3c-d
Minimum GCD current density	1.1 A g-1	—	—	Text Exact Reported	4 · Results and discussion · Fig. 3c-d
GCD electrolyte concentration	6.0 M PVA/KOH electrolyte	—	—	Text Exact Reported	1.3 Electrochemical measurements
GCD reversibility/shape	Symmetrical non-triangular shape with no distortion; indicates good reversibility and small equivalent series resistance	—	—	Text Qualitative	4 · Results and discussion · Fig. 3c
GCD voltage window	0-1.5 V	—	—	Text Exact Reported	1.3 Electrochemical measurements

Ragone energy-power analysis

Ni-Zn MOF//Ni-Zn MOF split-cell symmetric device (SC-SD) · Electrode

Energy density and power density of the Ni-Zn MOF//Ni-Zn MOF SC-SD at 1.5 V, estimated from total active-material mass according to SI equations.

Geometry: Split-cell symmetric device, Ni-Zn MOF//Ni-Zn MOF
Context: device using composite electrodes
Measurement source: 5 · Results and discussion · Fig. 4c-d

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Cell voltage for Ragone performance	1.5 V	—	—	Text Exact Reported	5 · Results and discussion · Fig. 4c-d
Discharge time calculated from best energy and powerMarked as a best value within this paper	approximately 133 s calculated as 3600 * 33.25 Wh kg-1 / 900 W kg-1	—	—	Calculated From Reported Approximate	5 · Results and discussion · Fig. 4c-d
Discharge time calculated from high-power point	approximately 5.5 s calculated as 3600 * 7.56 Wh kg-1 / 4950 W kg-1	—	—	Calculated From Reported Approximate	5 · Results and discussion · Fig. 4c-d
Gel electrolyte concentration from abstract	6 M gel electrolyte	—	—	Text Exact Reported	1 · Abstract
Best energy densityMarked as a best value within this paper	33.25 Wh kg-1 at 900 W kg-1	—	—	Text Exact Reported	1, 5 · Abstract; Results and discussion · Fig. 4c-d
Energy density retained at high power	7.56 Wh kg-1 at 4950 W kg-1	—	—	Text Exact Reported	5 · Results and discussion · Fig. 4d
Power density at best energy density	900 W kg-1	—	—	Text Exact Reported	1, 5 · Abstract; Results and discussion · Fig. 4c-d
High power-density pointMarked as a best value within this paper	4950 W kg-1	—	—	Text Exact Reported	5 · Results and discussion · Fig. 4d