H2 Sensing Response of Flame-Spray-Made Ru/SnO2 Thick Films Fabricated from Spin-Coated Nanoparticles

Sensors

Chaikarn Liewhiran¹  Nittaya Tamaekong³  Anurat Wisitsoraat² 

[1] Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai, 50202, Thailand; E-Mail:;National Electronics and Computer Technology Center, Pathumthani, 12120, Thailand; E-Mail:;Nanoscience Research Laboratory, Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai, 50202, Thailand; E-Mail:

关键词: SnO₂;    ruthenium;    flame spray pyrolysis;    H₂ sensor;   

DOI  :  10.3390/s91108996

来源: mdpi

【 摘 要 】

High specific surface area (SSA_BET: 141.6 m²/g) SnO₂ nanoparticles doped with 0.2–3 wt% Ru were successfully produced in a single step by flame spray pyrolysis (FSP). The phase and crystallite size were analyzed by XRD. The specific surface area (SSA_BET) of the nanoparticles was measured by nitrogen adsorption (BET analysis). As the Ru concentration increased, the SSA_BET was found to linearly decrease, while the average BET-equivalent particle diameter (d_BET) increased. FSP yielded small Ru particles attached to the surface of the supporting SnO₂ nanoparticles, indicating a high SSA_BET. The morphology and accurate size of the primary particles were further investigated by TEM. The crystallite sizes of the spherical, hexagonal, and rectangular SnO₂ particles were in the range of 3–10 nm. SnO₂ nanorods were found to range from 3–5 nm in width and 5–20 nm in length. Sensing films were prepared by the spin coating technique. The gas sensing of H₂ (500–10,000 ppm) was studied at the operating temperatures ranging from 200–350 °C in presence of dry air. After the sensing tests, the morphology and the cross-section of sensing film were analyzed by SEM and EDS analyses. The 0.2%Ru-dispersed on SnO₂ sensing film showed the highest sensitivity and a very fast response time (6 s) compared to a pure SnO₂ sensing film, with a highest H₂ concentration of 1 vol% at 350 °C and a low H₂ detection limit of 500 ppm at 200 °C.

【 授权许可】

CC BY   
© 2009 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.