Hydrogen-Sensing Properties And Reduction-Induced Sensing Mechanism Of Nickel Oxide Nanoplates

In this work, the reduction-induced H2 sensing mechanism of NiO nanoplates has been revealed by in-situ technique for the first time. Based on the in-situ TEM results, the satisfactory H2 sensing response of NiO is attributed to the reduction effect of H2 molecules on NiO, which does not follow the conventional sensing reaction between H2 molecules and oxygen-containing species on the material surface. With the guidance of the sensing mechanism, high-performance H2 sensors have been fabricated with MEMS micro-hotplates. Porous NiO nanoplates have been successfully synthesized and used as the sensing material for H2. The nanoplates have a porous structure and the pore size is about 4.5 nm. The detection limit of the sensor to H2 reaches 1 ppm, and the power consumption is only 17mW at the working temperature of 300 °C.