TY - JOUR

T1 - A MOF-Based Paramagnetic Oxygen Gas Sensor

AU - Efremov, Aleksandr A.

AU - Zhitkeyev, Ramis

AU - Livanovich, Kanstantsin S.

AU - Poryvaev, Artem S.

AU - Fedin, Matvey V.

N1 - The funding sources were the Russian Science Foundation (No. 24-43-10002) and Belarusian Republican Foundation for Fundamental Research (BRFFR, No. X23RNFM-048).

PY - 2025/12

Y1 - 2025/12

N2 - Precise and rapid oxygen sensing is crucial in a wide range of applications, from industrial process control to environmental monitoring and medical devices. In this proof-of-concept study, we present a new type of gas-phase oxygen sensing system that combines electron paramagnetic resonance (EPR) detection with a custom-designed sensing material: a metal–organic framework ZIF-8 composite with an embedded nitroxide spin probe. To enhance the sensing performance, we adapted the continuous wave EPR experiment protocol and optimized both the material structure and the gas delivery system. Static and flow experiments with dynamic exchange of the analyzed gas mixture were carried out. The sensing system significantly outperforms commercially available industrial models. It demonstrated reliable detection over a broad oxygen concentration range (0.02 to 95%) and response times from 550 ms to 2 s without sacrificing the accuracy. Due to detection simplicity, the sensor module can be further optimized by embedding it into an EPR-on-a-chip device, reducing the price and the module size. The integration of spin probes into a porous engineered framework offers a powerful approach for developing accurate and tunable oxygen sensors, which can meet the demands of both industry and research.

AB - Precise and rapid oxygen sensing is crucial in a wide range of applications, from industrial process control to environmental monitoring and medical devices. In this proof-of-concept study, we present a new type of gas-phase oxygen sensing system that combines electron paramagnetic resonance (EPR) detection with a custom-designed sensing material: a metal–organic framework ZIF-8 composite with an embedded nitroxide spin probe. To enhance the sensing performance, we adapted the continuous wave EPR experiment protocol and optimized both the material structure and the gas delivery system. Static and flow experiments with dynamic exchange of the analyzed gas mixture were carried out. The sensing system significantly outperforms commercially available industrial models. It demonstrated reliable detection over a broad oxygen concentration range (0.02 to 95%) and response times from 550 ms to 2 s without sacrificing the accuracy. Due to detection simplicity, the sensor module can be further optimized by embedding it into an EPR-on-a-chip device, reducing the price and the module size. The integration of spin probes into a porous engineered framework offers a powerful approach for developing accurate and tunable oxygen sensors, which can meet the demands of both industry and research.

UR - https://www.scopus.com/pages/publications/105024870679

UR - https://www.mendeley.com/catalogue/b661dd43-c8d2-34d4-a365-747622a953bc/

U2 - 10.1021/acs.analchem.5c05516

DO - 10.1021/acs.analchem.5c05516

M3 - Article

C2 - 41332274

VL - 97

SP - 27375

EP - 27382

JO - Analytical Chemistry

JF - Analytical Chemistry

SN - 0003-2700

IS - 49

ER -