Features:
Self-designed stainless steel in-situ/operando cell with minimum γ-ray working distance, 5mm. Aluminum oxide coated high-purity beryllium windows with high transmittance and good pressure resistance. High efficiency four-head heating rods. Dual gases supply system can be switched at will. Ultra-low vibration, linewidth of standard α-Fe is only 0.28mm/s. The radioactive source, sample cell and detector are assembled vertically, and can be flexibly disassembled. 50mCi 57Co(Rh) single-line radiation source and krypton filling LND proportional counter is used.
Applications:
This instrument can continuously measure in-situ/operando Mössbauer transmission spectrum (MTS) at any point between RT and 650K, ATM and 1MPa, under any oxidation/reduction atmosphere. It can also be used to measure air sensitive samples that require vacuum or atmosphere protection. The in-situ/operando system can be flexibly installed and disassembled, to perform ex-situ and in-situ characterization. The vertical assembly of instrument is conducive to the solid powder samples to keep evenly dispersed.
The Mössbauer spectroscopy is a technology that studies the behavior of resonant absorption of γ-rays by a specific atomic nuclei. Energy resolution is extremely high. Hyperfine interaction, phase information, valence state, coordination structure and magnetism property of Mössbauer nuclei can be obtained. The Mössbauer spectroscopy uses keV-level γ-rays with low attenuation (does not require a vacuum environment). It can be observed under high temperature, high pressure, various gas atmosphere, as well as induced by external magnetic field, microwave, ultrasound and light, etc., to observe the electronic, structural, and magnetic evolution information in real working conditions.
This in-situ device is an ideal choice for studying the structure-activity relationship and catalytic mechanism of heterogeneous Fe-containing thermal reaction catalyst, such as carbon monoxide oxidation and selective oxidation, water-gas shift reaction/reverse water-gas conversion reaction, Fischer-Tropsch synthesis Fe-based catalysis, and carbon dioxide hydrogenation, synthesis and decomposition of ammonia and solid-phase hydrogen storage materials,etc.
The in-situ/operando cell has a diameter of 15mm and a thickness up to 3mm. Enriched isotope 57Fe is recommended to be used for in-situ experiment sample preparation. For conventional measurement, the recommended value of the best absorption thickness of Fe in the sample is 10mg/cm2.
The MTS and Conversion Electron Mössbauer Spectroscopy (CEMS) modules can be switched. The MTS mainly obtains the bulk information of sample, while the CEMS mainly obtains the surface information. The unique depth selection characterization can be performed by selecting electrons of different energies for detection. It is an essential and powerful tool for surface chemistry.
