Mining Metal-Biomolecular Framework/PANI Composite CO Sensor: Material Synthesis, Gas Sensing Performance and Mechanism

In addressing the issue of poor gas sensitivity in semiconductor CO sensor materials used in mining, such as pure PANI. This study utilized an ice-water bath in combination with an in-situ polymerization method to synthesize a new composite material consisting of Cu(II)-racemic glutamate nanofibers and PANI. The morphology, structure, and chemical bonds of the composite material were analyzed using scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) and spectral analysis. The material's ability to detect CO (100-500 ppm) at room temperature was investigated, revealing a response value of up to 6.8 % for 400 ppm CO detection when the composite material was deposited on a ceramic interdigital electrode. The material exhibited good selectivity and responsiveness to CO detection at room temperature, attributed to the heterojunction formed between Cu(II)-racemic glutamate nanofibers and PANI, which enhanced carrier migration. Consequently, the Cu(II)-racemic glutamate nanofiber/PANI composite(Cu(II)-RGlu/PANI) material shows promise as a high-performance sensing material for CO detection at room temperature and as a low-power, integrable sensor material for underground coal mines. This research contributes to the development of a theoretical framework for such applications. This paper selectes MBioFs with copper ions as the metal center to design an MBioFs/PANI composite suitable for CO gas sensors. The morphology and nanostructure of the prepared materials were thoroughly analyzed, followed by testing their gas-sensing properties. Subsequently, the gas sensing mechanism of composite materials was proposed and discussed in detail. image