Electrospun Bi-doped SnO₂ porous nanosheets for highly sensitive nitric oxide detection

The real-time monitoring of NO in the low-concentration range from the ppb- to ppm-level is of great importance in the field of healthcare; however, accomplishing this is still challenging owing to the technical issues regarding highly efficient and selective sensing materials. In this study, we demonstrate the highly sensitive and selective detection of NO by Bi-doped SnO₂ two-dimensional ultrathin nanosheets with porous structures, fabricated using a facile one-step electrospinning method. It was found that the SnO₂ with 0.75 mol% Bi exhibits the highest sensitivity of 217-10 ppm of NO at a relatively low temperature of 75 °C. Further, a low detection limit of 50 ppb; high selectivity; and good stability have also been achieved. Further detailed analysis indicates that the promising sensing properties can be attributed to the ultrathin nanosheet structure, which has a high surface area and abundant pores. These results indicate that 2D metal-oxide ultrathin nanosheets achieve superior gas-sensing performance, and Bi-doped SnO₂ is a potential material for use in the real-time and low-power detection of NO.