VLS Growth of Highly Oriented SnO₂Nanorods and ZnO Hybrid Films for Gas Sensing Measurements

Abstract

Tin Oxide (SnO 2 ) nanorods have been successfully grown on a p-type Si substrate by a low-temperature vapor-liquid-solid (VLS) technique. Tin chloride and zinc chloride powders were used as starting materials. Surface morphologies and structural properties of the SnO 2 nanorods were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The SEM images shows distinct hierarchical growth of SnO 2 as well as the mixture with ZnO microstructures. The structural studies demonstrated rutile crystal structure SnO 2 nanorods with square-shaped facets of 40-60 nm in cross section size and 2 μm in length approximately and ZnO microrods of 10 μm diameter and 50 μm length. The fabrication of a gas sensor for acetone and ethanol vapors is also reported and its properties are discussed.

Photochemical Decoration of Metal and Metal-Oxide Nanoparticles on Highly Oriented SnO2Nanorod Films for Improved Hybrid Gas Sensors and Photo-Detectors

“…The substrate was cleaned from the remaining solvent using nitrogen gas, then, the growth of tin oxide nanorods was achieved using the method reported in a previous study. 1 A mixture of zinc dichloride (ZnCl 2 ) powder 99% purity and tin dichloride (SnCl 2 ) anhydrous powder 99.9% purity (4:1 weight ratio respectively) were grounded and placed at the bottom of an alumina ceramic boat and the previously cleaned silicon substrate was placed above the powder mixturestanding on the top of the boat. The previous setup was placed inside a regular muffle furnace in presence of oxygen and the temperature was set to gradually increase at a rate of 10 • C/min.…”

“…The two arms flow configuration was used as described in detail in a previous study. 1 The sensitivity response over time of the hybrid devices was then compared with the response of the reference device. Oxygen gas was introduced afterwards for full recovery of the sensor before the next sensing cycle.…”

“…Tin Oxide (SnO 2 ) nanostructures have been object of extensive studies due to a wide range of properties that makes this material suitable for several applications such as field-effect transistors, 8,11 lithium ion batteries, 3,25 transparent devices 26 gas sensors 1,6,10 and photo-detectors 4,20,26 among others.…”

Multilayered Approach for TiO2 Hollow-Shell-Protected SnO2 Nanorod Arrays for Superior Lithium Storage

“…Semiconductors such as tin dioxide (SnO 2 ) and similar metal oxide materials such as titanium dioxide (TiO 2 ) have gained significant attention for technological innovations because of their lithium storage properties and their nontoxic nonreactive behavior. , SnO 2 is well-known for its potential applications in Li-ion batteries, photodetectors, and gas sensors. − On the other hand, TiO 2 possesses a highly active catalytic surface, which serves as a photocatalyst in solar cells, and it is used in corrosion protection and Li-ion batteries as well. , Other than TiO 2 , nanocarbon materials such as graphene, carbon nanotubes, and graphene oxide have been coupled with SnO 2 as a capacity enhancer for Li-ion storage with promising results but also with a major disadvantage being the high nanocarbon toxicity and safety. − TiO 2 anodes have shown reversible capacity, high power density, and nontoxic behavior, which make this material a very safe candidate for applications in batteries, with the only disadvantage of TiO 2 being its poor energy density. − SnO 2 promotes considerably higher lithium storage capacity than graphite, which makes it a promising material for lithium storage devices; however, recent attempts in developing high-performance SnO 2 -based Li-ion batteries are encountering disadvantages such as poor cycling stability. One of the big challenges for SnO 2 anodes used in batteries is the severe volume expansion and structural pulverization that cause a reduction in the cycling performance in Li-ion batteries. , …”