HYDROGEN SENSOR BASED ON PALLADIUM NANODENDRITE/GRAPHENE NANOCOMPOSITE AND METHOD OF FABRICATING THE SAME

摘要

The present invention relates to a hydrogen sensor based on palladium nanodendrites/graphene nanocomposite and a fabrication method thereof. Palladium (Pd) nanodendrites (porous Pd nanospheres) in the present invention is synthetized by a single simple stage of a chemical route by a fast reaction process of Pd precursor salts. Pd dendrites in a highly uniform colloid type, having a size of 60 to 70 nm is reduced into a graphene flake to form Pd dendrites graphene hybrid by hydrazine (reductant) in a first reaction stage. A resistance type sensor used with the Pd dendrites graphene has a detection range from 1,000 ppm to 1 ppm and good linearity at room temperature. Moreover, hydrogen (H2) sensor shows a distinct reaction at low working temperatures of room temperature equal to or less than 50C even in a low hydrogen concentration range from 1 ppm to 10 ppm. Compared with the previous invention of the inventor, related to H2 detection based on Pd graphene composite/hybrid, a new Pd dendrites graphene hybrid has advantages of a high reaction value, good reproducibility, a fast reaction/restoration time, and a less hysteresis at low temperatures, although there is a weakness of a decrease in reaction at high temperatures (100C). The advantages in a calculation result of hydrogen (H2) sensing come from a high ratio of area to volume and high porosity of the Pd dendrites nanostructure.