Cobalt (Co) Foil for Quartz Crystal Microbalance Electrochemical Applications
| Brand | Hefei Kejing |
|---|---|
| Origin | Anhui, China |
| Manufacturer Type | Authorized Distributor |
| Origin Classification | Domestic (PRC) |
| Model | Co Foil |
| Price Range | USD 0.15–1,500.00 (per piece, volume-dependent) |
| Thickness | 0.01–1.0 mm |
| Packaging | Vacuum-sealed in Class 100 cleanroom bags, stored and shipped under Class 1000 cleanroom conditions |
Overview
Cobalt (Co) foil is a high-purity, mechanically stable metallic substrate engineered for integration into electrochemical quartz crystal microbalance (EQCM) systems. As a working electrode material, cobalt foil enables real-time, in situ mass monitoring during redox-driven interfacial processes—such as metal deposition/dissolution, polymer film growth, ion insertion, and catalytic surface reactions—by coupling electrochemical control with nanogram-level mass sensitivity (<0.1 ng resolution typical for 5 MHz AT-cut crystals). Its face-centered cubic (FCC) lattice structure, moderate standard reduction potential (E°Co²⁺/Co = −0.28 V vs. SHE), and well-defined surface oxide passivation behavior make it particularly suitable for fundamental studies of battery electrode kinetics, corrosion science, and electrocatalysis in aqueous and non-aqueous electrolytes.
Key Features
- High-purity cobalt (≥99.95% Co, trace metals quantified by ICP-MS; Fe, Ni, Cu < 5 ppm each)
- Controlled thickness tolerance: ±5% across 0.01–1.0 mm range, with surface roughness (Ra) < 0.2 µm as-measured by contact profilometry
- Electropolished finish available upon request to minimize nucleation heterogeneity during electrodeposition
- Thermally stable up to 400 °C in inert atmosphere—enabling post-deposition annealing without substrate degradation
- Compatible with standard EQCM sensor holders (e.g., CH Instruments, Gamry, Ivium) via conductive epoxy or spring-loaded clamping
- Pre-characterized electrochemical response: cyclic voltammetry in 0.1 M KCl + 1 mM CoSO₄ shows reversible Co²⁺/Co⁰ redox peaks with ΔEp < 65 mV and peak current ratio (ipa/ipc) within 0.95–1.05
Sample Compatibility & Compliance
Cobalt foil is supplied in accordance with ISO 14644-1 Class 5 (ISO Class 5 equivalent to Federal Standard 209E Class 100) cleanroom handling protocols. Each lot undergoes certificate-of-analysis (CoA) verification including residual solvent testing (GC-MS), particulate count per ASTM F329 (≤5 particles ≥0.5 µm per cm²), and oxygen content (≤50 ppm by LECO combustion analysis). The material meets ASTM B775-22 specifications for unalloyed cobalt sheet and foil, and complies with RoHS Directive 2011/65/EU Annex II substance restrictions. For regulated laboratories operating under GLP or GMP frameworks, full traceability—including heat number, rolling batch ID, and QC test reports—is provided with every shipment.
Software & Data Management
While the Co foil itself is a passive consumable, its use is fully supported within industry-standard EQCM data acquisition environments. It integrates seamlessly with QCM software platforms such as QCM-IQ (SensQ), NOVA (Metrohm Autolab), and EC-Lab (BioLogic), enabling synchronized acquisition of frequency shift (Δf), dissipation (ΔD), current (I), and potential (E) time-series. All raw data formats (e.g., .txt, .csv, .mpt) are compatible with MATLAB-based custom analysis toolboxes for Sauerbrey mass conversion, Voigt-model viscoelastic fitting, and charge-mass correlation mapping. Audit trails, user access logs, and electronic signatures align with FDA 21 CFR Part 11 requirements when deployed on validated instrument workstations.
Applications
- In situ monitoring of lithium-ion cathode material synthesis (e.g., LiCoO₂ nucleation on Co foil substrates)
- Quantitative study of hydrogen evolution reaction (HER) intermediates on cobalt-based electrocatalysts
- Real-time tracking of polymeric film formation during electropolymerization of aniline or pyrrole
- Corrosion inhibition evaluation via adsorption isotherm modeling of inhibitor molecules on Co surfaces
- Model system for studying solid-electrolyte interphase (SEI) formation kinetics in carbonate-based electrolytes
- Calibration reference for EQCM sensitivity factor (Cf) determination using Faradaic mass deposition (e.g., Ag⁺/Ag plating)
FAQ
Is this cobalt foil pre-annealed to relieve cold-work stress?
Yes—standard stock undergoes vacuum annealing at 600 °C for 2 hours prior to packaging to ensure crystalline homogeneity and reproducible electrochemical response.
Can I order custom-cut geometries (e.g., 8-mm-diameter discs) with edge beveling?
Yes. Custom die-cutting, laser ablation, and precision wire EDM services are available with lead times of 5–7 business days.
What cleaning protocol do you recommend before EQCM mounting?
We recommend sequential ultrasonication in acetone (5 min), ethanol (5 min), and Milli-Q water (5 min), followed by N₂ blow-drying and UV-ozone treatment (15 min) to remove organic contaminants and native oxides.
Does the foil exhibit magnetic interference in high-sensitivity QCM-D measurements?
No—bulk cobalt’s ferromagnetic Curie temperature (1121 °C) far exceeds operational ranges; no measurable magnetic coupling is observed in QCM-D setups operating below 100 °C.
Are certificates of conformance available for export to EU or US regulatory jurisdictions?
Yes—each order includes an ISO/IEC 17025-accredited CoC, RoHS declaration, and REACH SVHC statement, all digitally signed and timestamped.
