Electrochemistry Application — Construction of sulfur vacancies enriched hollow zinc cobalt bimetallic sulfides for high-performance supercapacitors

10 measurement groups · 38 results

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

CV and GCD of activated carbon negative electrode

Voltammetry Galvanostatic cycling

activated carbon negative electrode · Electrode

AC tested as negative electrode for HSC; CV rectangular and GCD linear; 3 M KOH.

Geometry: activated carbon negative electrode
Context: Device negative electrode component
Measurement source: p006 · 3.2. Electrochemical measurements · Fig. S12

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
activated carbon specific capacity at 1 A g-1	179.2 C g-1 at 1 A g-1	—	—	Text Exact Reported	p006 · 3.2. Electrochemical measurements · Fig. S12

GCD cycling stability

Galvanostatic cycling

Zn0.3Co2.7S4 working electrode on nickel foam · Electrode

1000 cycles at 10 A g-1; Zn0.3Co2.7S4 compared with Co3S4.

Geometry: active material/acetylene black/PTFE on nickel foam
Context: Target and Zn-free control electrodes
Measurement source: p006 · 3.2. Electrochemical measurements · Fig. 3i

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Co3S4 electrode capacity retention after 1000 cycles	63.4% after 1000 cycles at 10 A g-1	—	—	Text Exact Reported	p006 · 3.2. Electrochemical measurements · Fig. 3i
Zn0.3Co2.7S4 electrode capacity retention after 1000 cyclesMarked as a best value within this paper	84.7% after 1000 cycles at 10 A g-1	—	—	Text Exact Reported	p006 · 3.2. Electrochemical measurements · Fig. 3i

Electrochemical impedance spectroscopy

Impedance spectroscopy

Zn0.3Co2.7S4 working electrode on nickel foam · Electrode

Frequency range 10 mHz to 100 kHz in 3 M KOH; fitted equivalent circuit for Rs and Rct.

Geometry: active material/acetylene black/PTFE on nickel foam
Context: Target and control sulphide electrodes
Measurement source: p002 · 2.4. Electrochemical measurements

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Co3S4 EIS fitted low-frequency slope	1.31	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1
Zn0.15Co2.85S4 EIS fitted low-frequency slope	1.95	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1
Zn0.3Co2.7S4 EIS fitted low-frequency slopeMarked as a best value within this paper	2.58	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1
Zn0.45Co2.55S4 EIS fitted low-frequency slope	1.42	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1
Co3S4 charge-transfer resistance Rct	0.18 ohm	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1
Zn0.15Co2.85S4 charge-transfer resistance Rct	0.13 ohm	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1
Zn0.3Co2.7S4 charge-transfer resistance RctMarked as a best value within this paper	0.11 ohm	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1
Zn0.45Co2.55S4 charge-transfer resistance Rct	0.21 ohm	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1
Co3S4 equivalent series resistance Rs	0.74 ohm	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1
Zn0.15Co2.85S4 equivalent series resistance Rs	0.68 ohm	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1
Zn0.3Co2.7S4 equivalent series resistance RsMarked as a best value within this paper	0.69 ohm	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1
Zn0.45Co2.55S4 equivalent series resistance Rs	0.77 ohm	—	—	SI Table Exact Reported	p008 · Table S1 · Table S1

Galvanostatic charge-discharge comparison in a three-electrode cell

Galvanostatic cycling

Co3S4 working electrode on nickel foam · Electrode

Specific capacities compared for Co3S4, Zn0.15Co2.85S4, Zn0.3Co2.7S4 and Zn0.45Co2.55S4 at 1 A g-1; 3 M KOH.

Geometry: active material/acetylene black/PTFE on nickel foam
Context: Control comparison against target Zn0.3Co2.7S4 electrode
Measurement source: p005 · 3.2. Electrochemical measurements · Fig. 3d,e

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Co3S4 specific capacity at 1 A g-1	287.1 C g-1 at 1 A g-1	—	—	Text Exact Reported	p005 · 3.2. Electrochemical measurements · Fig. 3d,e
Zn0.15Co2.85S4 specific capacity at 1 A g-1	351.8 C g-1 at 1 A g-1	—	—	Text Exact Reported	p005 · 3.2. Electrochemical measurements · Fig. 3d,e
Zn0.45Co2.55S4 specific capacity at 1 A g-1	266.9 C g-1 at 1 A g-1	—	—	Text Exact Reported	p005 · 3.2. Electrochemical measurements · Fig. 3d,e

Galvanostatic charge-discharge in a three-electrode cell

Galvanostatic cycling

Zn0.3Co2.7S4 working electrode on nickel foam · Electrode

0-0.45 V potential window; current densities 1, 2, 4, 6, 8 and 10 A g-1 in 3 M KOH.

Geometry: active material/acetylene black/PTFE on nickel foam
Context: Electrode composite using best-performing derived sulphide active material
Measurement source: p002 · 2.4. Electrochemical measurements

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Zn0.3Co2.7S4 specific capacity at 10 A g-1	262.0 C g-1 at 10 A g-1	—	—	Text Exact Reported	p005 · 3.2. Electrochemical measurements · Fig. 3c,e
Zn0.3Co2.7S4 specific capacity at 1 A g-1Marked as a best value within this paper	545.9 C g-1 at 1 A g-1	—	—	Text Exact Reported	p005 · 3.2. Electrochemical measurements · Fig. 3c,e
Zn0.3Co2.7S4 specific capacity at 2 A g-1	473.2 C g-1 at 2 A g-1	—	—	Text Exact Reported	p005 · 3.2. Electrochemical measurements · Fig. 3c,e
Zn0.3Co2.7S4 specific capacity at 4 A g-1	394.8 C g-1 at 4 A g-1	—	—	Text Exact Reported	p005 · 3.2. Electrochemical measurements · Fig. 3c,e
Zn0.3Co2.7S4 specific capacity at 6 A g-1	340.5 C g-1 at 6 A g-1	—	—	Text Exact Reported	p005 · 3.2. Electrochemical measurements · Fig. 3c,e
Zn0.3Co2.7S4 specific capacity at 8 A g-1	295.8 C g-1 at 8 A g-1	—	—	Text Exact Reported	p005 · 3.2. Electrochemical measurements · Fig. 3c,e

Hybrid supercapacitor CV and GCD

Voltammetry Galvanostatic cycling

Zn0.3Co2.7S4//AC aqueous hybrid supercapacitor · Electrode

Zn0.3Co2.7S4//AC device in 3 M KOH; operating voltage window selected as 0-1.6 V; CV at different windows and scan rates, GCD at 1-10 A g-1.

Geometry: asymmetric aqueous HSC device
Context: Composite device using derived sulphide positive electrode and AC negative electrode
Measurement source: p006 · 3.2. Electrochemical measurements · Fig. 4c-e

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
HSC specific capacitance at 1 A g-1Marked as a best value within this paper	70.1 C g-1 at 1 A g-1	—	—	Text Exact Reported	p007 · 3.2. Electrochemical measurements · Fig. 4f
HSC selected operating voltage window	0-1.6 V	—	—	Text Exact Reported	p007 · 3.2. Electrochemical measurements · Fig. 4c

Hybrid supercapacitor cycling stability and coulombic efficiency

Zn0.3Co2.7S4//AC aqueous hybrid supercapacitor · Electrode

Cycling at 4 A g-1 for 5000 cycles; coulombic efficiency monitored; two devices in series powered a blue LED.

Geometry: asymmetric aqueous HSC device
Context: Composite device
Measurement source: p006 · Fig. 4 caption · Fig. 4h

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
HSC coulombic efficiency during cycling	approximately 100% over 5000 cycles	—	visual estimate from Fig. 4h blue curve	Visual Estimate Approximate	p006 · Fig. 4 caption · Fig. 4h
HSC capacity retention after 5000 cycles	~ 71.2% at 4 A g-1 after 5000 cycles	—	—	Text Approximate	p007 · 3.2. Electrochemical measurements · Fig. 4h

Ragone energy and power density calculation

Zn0.3Co2.7S4//AC aqueous hybrid supercapacitor · Electrode

Energy density and power density calculated from HSC GCD curves using E = Cs x delta V / 7.2 and P = 3600E / delta t.

Geometry: asymmetric aqueous HSC device
Context: Composite device
Measurement source: p002 · 2.4. Electrochemical measurements

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
maximum HSC energy densityMarked as a best value within this paper	15.58 W h kg-1 at 800.11 W kg-1	—	—	Text Exact Reported	p007 · 3.2. Electrochemical measurements · Fig. 4g
HSC power density at maximum energy density	800.11 W kg-1	—	—	Text Exact Reported	p007 · 3.2. Electrochemical measurements · Fig. 4g

CV kinetic analysis using power-law ip = a v^b and capacitive/diffusion contribution separation

Voltammetry

Zn0.3Co2.7S4 working electrode on nickel foam · Electrode

Peak current density versus scan rate; surface capacitive contribution evaluated at 5-40 mV s-1.

Geometry: active material/acetylene black/PTFE on nickel foam
Context: Target Zn0.3Co2.7S4 electrode
Measurement source: p006 · 3.2. Electrochemical measurements · Fig. 3g,h

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
anodic b-value	0.53	—	—	Text Exact Reported	p006 · 3.2. Electrochemical measurements · Fig. 3g
cathodic b-value	0.49	—	—	Text Exact Reported	p006 · 3.2. Electrochemical measurements · Fig. 3g
surface-controlled contribution at 10 mV s-1	32.27%	—	—	Figure Axis Rounded Reported	p005 · Fig. 3 caption · Fig. 3h
surface-controlled contribution at 20 mV s-1	45.13%	—	—	Figure Axis Rounded Reported	p005 · Fig. 3 caption · Fig. 3h
surface-controlled contribution at 30 mV s-1	57.74%	—	—	Figure Axis Rounded Reported	p005 · Fig. 3 caption · Fig. 3h
surface-controlled contribution at 40 mV s-1Marked as a best value within this paper	70.09%	—	—	Text Exact Reported	p006 · 3.2. Electrochemical measurements · Fig. 3h
surface-controlled contribution at 5 mV s-1	23.47%	—	—	Figure Axis Rounded Reported	p005 · Fig. 3 caption · Fig. 3h

Cyclic voltammetry in a three-electrode cell

Voltammetry

Zn0.3Co2.7S4 working electrode on nickel foam · Electrode

CHI 760E workstation; platinum foil counter, SCE reference, 3 M KOH electrolyte; -0.1 to 0.6 V; scan rates 3-50 mV s-1; key figures use 5-40 mV s-1 and 10 mV s-1 comparisons.

Geometry: active material/acetylene black/PTFE on nickel foam
Context: Electrode composite using derived sulphide active material
Measurement source: p002 · 2.4. Electrochemical measurements

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
CV redox behaviour	distinct separated redox peak corresponding to M-S/M-S-OH reaction	—	—	Text Qualitative	p004 · 3.2. Electrochemical measurements · Fig. 3a