Amperometric sensor for the detection of hydrogen stable isotopes based on Pt nanoparticles confined within single-walled carbon nanotubes (SWNTs)

The development of hydrogen-based energy and nuclear energy requires new sensing material and high-performance gas sensor for hydrogen stable isotopes, hydrogen (H2) and deuterium (D2). Amperometric gas sensors based on SWNT-filled Pt composite material (Pt-SWNT-in) to combine the good electronic properties of SWNTs and space-confined effect of Pt catalyst have been investigated for detecting H2 and D2. The Pt-SWNT-in electrode shows an excellent linear response in a wide range of 160–8000 ppm hydrogen in N2 atmosphere with the correlation coefficient of 0.9993, and compared to the electrode with Pt nanoparticles supported outside of SWNTs, its sensitivity per Pt loading is 3 times, moreover, it gives larger response current for detection of H2 in air and D2 in N2 atmosphere. Additionally, the Pt-SWNT-in electrode provides a response current to deuterium 0.9 times that to hydrogen in N2. The results present the Pt-SWNT-in electrode with superior sensitivity, selectivity, stability and a response variation for detection of hydrogen and deuterium, which would take advantage of the space-confined effect of SWNTs on Pt catalysts to enhance the sensor performance for detecting hydrogen stable isotopes, and provide an approach to discriminate between hydrogen and deuterium.