Highly Selective Detection of Hydrogen Sulfide by Simple Cu-CNTs Nanocomposites

The presented work is devoted to the preparation of nanocomposites based on multiwall carbon nanotubes (MWCNTs) and copper (Cu) nanoparticles by a simple chemical method, and to study their sensing properties to hydrogen sulfide (H2S) gas. The Cu decorated multiwall carbon nanotubes (MWCNTs/Cu) were prepared by the deposition of very thin Cu layers on the pristine and functionalized multiwall carbon nanotubes (f-MWCNTs) using both physical (electron beam evaporation (EBE)) and chemical (electrochemical deposition) methods. MWCNTs/Cu prepared in the two above-mentioned ways, their sensing properties were studied, and the results were comparatively analyzed. The effect of the chemical functionalization of MWCNTs by oxygen-containing groups on the sensing properties of these f-MWCNT/Cu nanocomposites has been investigated. All the prepared sensors demonstrated high sensitivity and selectivity to H2S in the air at room temperature. The f-MWCNT/Cu structure obtained by the chemical method demonstrated about 5 times (similar to 400%) higher sensitivity (increment R/R-0) to H2S gas compared to the similar structure obtained by the physical method. The temperature effect on sensory characteristics (response and self-recovery time) of the f-MWCNTs/Cu structure was also studied.

Automated summary

This work focuses on the preparation of nanocomposites based on multiwall carbon nanotubes (MWCNTs) and copper (Cu) nanoparticles using a chemical method, and investigates their sensing properties to hydrogen sulfide (H2S) gas. Different deposition methods were used to fabricate Cu decorated multiwall carbon nanotubes (MWCNTs/Cu), and their sensing properties were studied and compared. The impact of chemical functionalization of MWCNTs on the sensing properties of these nanocomposites was also examined. The obtained sensors demonstrated high sensitivity and selectivity to H2S gas at room temperature, and the chemical method showed higher sensitivity compared to the physical method.