In this work, Sn⁴⁺ doped NiO nanofibers are modified by different contents of Rh₂O₃ through a facile electrospinning method to improve the gas sensing properties, especially the humidity tolerance, response value and detection limit. The morphological characterization indicates that the hollow nanostructures are still maintained after loading Rh₂O₃. Gas sensing investigation demonstrates that 6 at% Sn⁴⁺ doped NiO nanofibers modified with 6 at% Rh₂O₃ exhibit the highest response to triethylamine (28.3-20 ppm) with low detection limit (50 ppb) at a relatively low working temperature (165 degrees C), which are obviously superior to those (16.6-100 ppm, 500 ppb and 180 degrees C) of 6 at% Sn⁴⁺ doped NiO nanofibers without Rh₂O₃ modification. The response value to 20 ppm triethylamine is only changed about 35.7% as the relative humidity increases from 35% to 95%. The humidity tolerance of the optimal sensor is also improved after Rh₂O₃ modification including the baseline resistance and gas response changes. Furthermore, the baseline resistances of the optimal gas sensors don't become higher after Rh₂O₃ modification. These phenomena can be mainly attributed to the improved catalytic effect and increased surface defects caused by Rh₂O₃ modification.

原文链接：https://doi.org/10.1016/j.snb.2023.133481