A dimethyl disulfide gas sensor based on nanosized Pt-loaded tetrakaidecahedral α -Fe 2 O 3 nanocrystals.

Surface modification by employing precious metals is one of the most effective ways to improve the gas-sensing performance of metal oxide semiconductors. Pure α -Fe 2 O 3 nanoparticles and Pt-modified α -Fe 2 O 3 nanoparticles were prepared sequentially using a rather simple hydrothermal synthesis and impregnation method. Compared with the original α -Fe 2 O 3 nanomaterials, the Pt- α -Fe 2 O 3 nanocomposite sensor shows a higher response value ( R a / R g  = 58.6) and a shorter response/recovery time (1 s/168 s) to 100 ppm dimethyl disulfide (DMDS) gas at 375 °C. In addition, it has better selectivity to DMDS gas with the value of more than 9 times higher than the other target gases at 375 °C. This study indicates that the Pt- α -Fe 2 O 3 nanoparticle sensor has good prospects and can be used as a low-cost and effective DMDS gas sensor.