The modular design of the electrochemical in-situ XAFS reaction cell focuses on improving experimental flexibility, data reliability, and operational convenience. It achieves multi scenario adaptation and performance optimization through standardized functional units, and its design principles are mainly reflected in the following aspects:
1. Function module splitting and standardized interface design
The reaction tank is divided into optical module, electrochemical module, fluid control module, and environmental control module, and each module is quickly assembled and replaced through standardized interfaces (such as threads and buckles). For example:
Optical module: using detachable Kapton film or quartz window, supporting transmission/fluorescence dual-mode switching, window thickness and material customized according to X-ray energy range (such as 2.5-20keV), reducing signal attenuation.
Electrochemical module: Integrated three electrode system (working electrode, reference electrode, counter electrode), electrode interface adopts standardized plug-in design, compatible with different materials (such as carbon paper, platinum sheet) and sizes (such as 1.5 × 3cm ²), supports wide range regulation of potential range ± 5V and current density 0.1-100mA/cm ².
2. Multi environment compatibility design
Modular design supports stable operation of the reaction tank under gas phase, liquid phase, high temperature and high pressure conditions
Gas phase environment: By sealing the chamber and gas inlet and outlet modules, precise introduction of reaction gases such as CO ₂ and O ₂ can be achieved (flow rate 0.1-10mL/min), and coupled with gas chromatography interface, real-time monitoring of reaction products can be achieved.
High temperature and high pressure environment: PEEK or titanium alloy materials are used to construct pressure resistant chambers (such as 30MPa), integrated with liquid nitrogen cooling or electric heating modules (temperature range 4.2-973K), and thermal radiation interference to the detector is reduced through insulation layers (such as 5mm quartz lining).
3. Dynamic signal optimization design
In response to the issue of signal susceptibility to interference in in-situ XAFS experiments, modular design improves signal-to-noise ratio through the following strategies:
Liquid film thickness regulation: The liquid film thickness between the working electrode and the light window can be adjusted (0.1-5mm) to balance the reaction resistance and X-ray absorption intensity, avoiding the masking of low content element (such as Fe) signals by solvents (such as water).
Stray light suppression: The optical window and X-ray incidence angle are designed to be 45 ° to reduce secondary fluorescence interference caused by stainless steel cavity excitation; Using high-purity quartz or Be windows (transmittance>90%) to reduce background noise.
4. Rapid maintenance and scalability design
The modular structure supports single person disassembly and assembly within 10 minutes, and each component (such as electrodes and sealing rings) can be independently replaced to reduce maintenance costs. At the same time, standardized interfaces (such as M6 threaded holes and SMA fiber optic interfaces) are reserved to support the integration with technologies such as Raman spectroscopy and electrochemical impedance spectroscopy (EIS), expanding experimental capabilities. For example, by integrating multi wavelength LED light modules, synergistic research between photocatalysis and electrocatalysis can be achieved.