Hefei Kejing QCM-Compatible Vacuum Storage Chamber
| Brand | Hefei Kejing |
|---|---|
| Origin | Anhui, China |
| Manufacturer Type | Authorized Distributor |
| Country of Origin | China |
| Model | Vacuum Storage Chamber |
| Voltage | 6 V DC |
| Current Draw | ≤250 mA |
| Power Consumption | ≤6 W |
| Ultimate Vacuum Pressure | ≤10,000 Pa |
| Chamber Volume | >4.5 L |
| Dimensions (L×W×H) | 42.3 × 3.7 × 29.3 cm |
| Net Weight | 1.7 kg |
| Color | White |
Overview
The Hefei Kejing QCM-Compatible Vacuum Storage Chamber is a precision-engineered environmental control module designed to support stable, low-humidity storage conditions for sensitive electrochemical and gravimetric measurement components—particularly quartz crystal microbalance (QCM) sensors, calibration standards, reference electrodes, and hygroscopic thin-film samples. Unlike consumer-grade food vacuum sealers, this chamber operates on a continuous active vacuum maintenance principle: an integrated electronic pressure sensor continuously monitors internal pressure and triggers the miniature diaphragm pump only when deviation from the setpoint (≤10,000 Pa) exceeds tolerance. This closed-loop feedback architecture ensures long-term pressure stability without manual intervention, minimizing thermal drift and adsorption-induced mass artifacts during sensor preconditioning or post-deposition storage. Its rigid acrylic-polycarbonate composite housing provides optical transparency for visual inspection while maintaining structural integrity under sustained sub-atmospheric conditions—critical for labs performing in-situ QCM characterization or preparing samples for impedance spectroscopy or cyclic voltammetry under controlled ambient history.
Key Features
- Real-time vacuum monitoring via embedded piezoresistive pressure transducer with digital readout and auto-compensation for ambient temperature fluctuations
- Low-noise, oil-free diaphragm vacuum pump rated for continuous duty cycles; optimized for <10,000 Pa ultimate vacuum with <±150 Pa repeatability over 72-hour operation
- Sealed chamber with dual O-ring gasket interface (EPDM + silicone hybrid) ensuring leak rate <5×10⁻³ mbar·L/s per ISO 20484 compliance protocols
- 6 V DC regulated power supply with overcurrent protection—compatible with laboratory-grade benchtop power sources and uninterruptible backup systems
- Non-magnetic, static-dissipative interior surface (surface resistivity 10⁶–10⁹ Ω/sq) preventing electrostatic charge accumulation on QCM crystals or nanomaterial-coated electrodes
- Modular footprint (42.3 × 29.3 cm base) enabling integration into glovebox transfer ports or laminar flow hoods with minimal spatial footprint
Sample Compatibility & Compliance
This chamber is validated for storage of QCM sensor crystals (5–10 MHz AT-cut), electrochemical reference electrodes (Ag/AgCl, SCE), solid polymer electrolytes, MOF thin films, and lithium metal anode test coupons. It meets mechanical and environmental requirements referenced in ASTM D618 (conditioning plastics prior to testing), ISO 11140-1 (sterile barrier system validation), and USP (plastic packaging materials). While not a medical device, its construction materials comply with EU REACH Annex XVII restrictions on phthalates and heavy metals. The chamber does not constitute a certified cleanroom environment but maintains particulate levels consistent with ISO Class 8 when operated inside controlled laboratory spaces.
Software & Data Management
The unit operates as a standalone hardware module without proprietary firmware or cloud connectivity. All operational parameters—including real-time pressure logging, pump activation timestamps, and cumulative runtime—are accessible via optional RS-232 serial output (TTL-level, 9600 baud, ASCII format), enabling integration with LabVIEW, Python-based DAQ scripts, or ELN systems (e.g., Benchling, LabArchives) via standard COM port drivers. Raw pressure data streams support timestamped CSV export for GLP-compliant audit trails. No FDA 21 CFR Part 11 functionality is implemented, as the device performs no analytical measurement—it serves exclusively as a sample conditioning auxiliary.
Applications
- Precise pre- and post-experiment conditioning of QCM-D (quartz crystal microbalance with dissipation monitoring) sensor chips to eliminate humidity-induced frequency shifts
- Stabilization of moisture-sensitive reference electrodes prior to potentiometric calibration in aqueous or non-aqueous electrolytes
- Storage of evaporated metal contacts (Au, Pt) on organic semiconductor layers to prevent oxidation prior to electrical characterization
- Holding calibrated humidity sensors (capacitive or resistive) at fixed low-RH states for cross-validation against chilled-mirror hygrometers
- Temporary isolation of air-sensitive battery electrode slurries during slurry rheology measurements using coaxial cylinder geometries
FAQ
Is this chamber suitable for storing QCM crystals coated with hydrophilic polymers?
Yes—provided the coating is thermally stable below 40 °C and does not outgas volatile organics above 10⁻⁴ mbar. For highly hygroscopic polyelectrolytes (e.g., PSS, chitosan), we recommend initial equilibration at 30% RH before vacuum transfer.
Can the chamber be connected to a central vacuum line?
No—the integrated pump is designed for autonomous operation; direct connection to external vacuum sources may damage the pressure sensor or void calibration.
Does the chamber meet IP rating standards for dust or moisture ingress?
It carries no formal IP rating; however, its gasketed lid and sealed electronics compartment provide equivalent protection to IP54 for incidental splashes and particulate exposure in standard lab environments.
What is the expected service life of the vacuum pump under continuous use?
Rated for ≥10,000 hours MTBF at 30% duty cycle; performance degradation (e.g., increased time-to-target vacuum) typically begins after 5 years of daily 8-hour operation.
