Electrochemistry Application — Overscreening-Driven Modulation of Ion Adsorption and Desorption in Conductive MOF Electrodes by Charging Rates

3 measurement groups · 20 results

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

Cyclic voltammetry with electrochemical quartz crystal microbalance (EQCM)

Voltammetry

Ni3(HITP)2 c-MOF film working electrode on Au-coated quartz · Electrode

CV across 10, 100 and 1000 mV s^-1 over -0.25 to 0.25 V versus PZC while quartz frequency was tracked; [EMIM][BF4] electrolyte at 60 deg C.

Temperature: 333
Geometry: c-MOF working electrode on Au-coated quartz, Pt counter electrode, Ag pseudoreference electrode
Context: pristine Ni3(HITP)2 film in [EMIM][BF4]
Measurement source: 2582 · Results and Discussion · Figure 1c,d

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Experimental CV potential window upper limit versus PZC	0.25 V	—	—	Caption Exact Reported	2582 · Figure 1 caption · Figure 1c
Experimental CV potential window lower limit versus PZC	-0.25 V	—	—	Caption Exact Reported	2582 · Figure 1 caption · Figure 1c
CV curve shape and reaction contribution	nearly rectangular CV curves; electrochemical reactions negligible	—	—	Qualitative Qualitative	2583 · Results and Discussion · Figure 1c
Maximum experimental CV scan rate	1000 mV s^-1	1 V s^-1	—	Text Exact Reported	2582 · Results and Discussion · Figure 1c,d
Minimum experimental CV scan rate	10 mV s^-1	0.01 V s^-1	—	Text Exact Reported	2582 · Results and Discussion · Figure 1c,d
c-MOF electrode mass loadingMarked as a best value within this paper	approximately 10 ug cm^-2	—	—	Text Approximate	2587 · Methods - EQCM Measurements
EQCM film rigidity	small dissipation changes; film remains rigid throughout testing	—	—	Caption Qualitative	S3 · Supplementary Figure 2 caption · Figure S2d
EQCM cell temperature	60 deg C	333.15 K	—	Text Exact Reported	2587 · Methods - EQCM Measurements

EQCM mass-charge deconvolution into [EMIM]+ and [BF4]- mole quantities, ionic currents and capacitance contributions

Ni3(HITP)2 c-MOF film working electrode on Au-coated quartz · Electrode

Measured mass and charge changes were decomposed using conservation of mass and charge with EMIM+ = 111 g mol^-1, BF4- = 87 g mol^-1, valences +1 and -1, and Faraday constant 96485 C mol^-1.

Temperature: 333
Geometry: same EQCM three-electrode setup as CV
Context: pristine Ni3(HITP)2 film in [EMIM][BF4]
Measurement source: 2587 · Methods - EQCM Data Processing · Figures 2a-c, 2h-i and S6

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Anion capacitance contribution at 10 mV s^-1	83%	0.83 fraction	—	Figure Axis Rounded Reported	2583 · Results and Discussion · Figure 2i
Anion capacitance contribution at 100 mV s^-1	72%	0.72 fraction	—	Figure Axis Rounded Reported	2583 · Results and Discussion · Figure 2i
Anion capacitance contribution at 1000 mV s^-1	57%	0.57 fraction	—	Figure Axis Rounded Reported	2584 · Results and Discussion · Figure 2i
Cation capacitance contribution at 10 mV s^-1	17%	0.17 fraction	—	Figure Axis Rounded Reported	2583 · Results and Discussion · Figure 2i
Cation capacitance contribution at 100 mV s^-1	28%	0.28 fraction	—	Figure Axis Rounded Reported	2583 · Results and Discussion · Figure 2i
Cation capacitance contribution at 1000 mV s^-1	43%	0.43 fraction	—	Figure Axis Rounded Reported	2583 · Results and Discussion · Figure 2i
Charging mechanism at high charging rate	ion exchange generally dominates at 1000 mV s^-1 / 10 ns simulation	—	—	Text Qualitative	2584 · Results and Discussion · Figure 2g
Charging mechanism at low charging rate	anion adsorption/desorption dominates at 10 mV s^-1 / quasi-static simulation	—	—	Text Qualitative	2583 · Results and Discussion · Figure 2a,d,g
High-rate mass hysteresis	hysteresis almost disappears at 1000 mV s^-1	—	—	Text Qualitative	2583 · Results and Discussion · Figure 1d
Low-rate EQCM mass-potential trend	mass monotonously increases with potential at 10 mV s^-1	—	—	Text Qualitative	2583 · Results and Discussion · Figure 1d,e
Intermediate-rate mass hysteresis	significant hysteresis at 100 mV s^-1	—	—	Text Qualitative	2583 · Results and Discussion · Figure 1d

Electrochemical impedance/Nyquist and specific capacitance versus potential for PZC

Impedance spectroscopy

Ni3(HITP)2 c-MOF film working electrode on Au-coated quartz · Electrode

Nyquist curves collected from 100 kHz to 10 MHz; specific capacitance observed at 10 mHz under different potentials.

Geometry: c-MOF film on Au-coated quartz, Ag pseudoreference
Context: pristine Ni3(HITP)2 film
Measurement source: S2 · Supplementary Figure 1 · Figure S1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Potential of zero chargeMarked as a best value within this paper	0.15 V vs Ag	—	—	Caption Exact Reported	S2 · Supplementary Figure 1 caption · Figure S1