Porous SnO2 nanospheres as sensitive gas sensors for volatile organic compounds detection

Abstract

Porous SnO(2) nanospheres with high surface areas have been synthesized through a solvothermal method in the absence of any templates. The structure and morphology of the resultant products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and nitrogen adsorption-desorption technique. The as-prepared SnO(2) porous nanospheres with the diameters ranging from 90-150 nm are composed of small nanocrystals with average sizes of less than 10 nm. Results demonstrated that the formation of porous SnO(2) nanospheres is ascribed to etching the center part of the nanospheres. It was found that hydrochloric acid and NaClO played important roles in determining the final morphologies of the porous SnO(2) nanospheres. The gas sensing properties of the as-prepared porous SnO(2) nanospheres were investigated. By the comparative gas sensing tests, the porous SnO(2) nanospheres exhibited a superior gas sensing performance toward ppb level 2-chloroethanol and formaldehyde vapor, implying promising applications in detecting toxic volatile organic compounds (VOCs).

Hierarchically porous indium oxide nanolamellas with ten-parts-per-billion-level formaldehyde-sensing performance

“…SSAs up to 90 m 2 g −1 have been reported for In 2 O 3 nanoparticles and their porous assemblies [11]. Although significant progresses with the lowest HCHO-detection limits down to 500 ppb have been achieved in the literature [13], the limits are still higher than 100 ppb and do not meet the requirement of practical applications. This should be due to that the active sites on the surfaces of the In 2 O 3 nanoparticles were not sufficient, because the SSAs of their assemblies were already very high.…”

Dandelion-like SnO2 microspheres on graphene oxide sheets with excellent photocatalytic properties

“…The SnO 2 nanomaterial used as gas sensors [5], lithium rechargeable batteries [6] and photocatalytic degradation of organic dyes [7], depends strongly on its size and morphology. SnO 2 nanostructures, including nanoparticles [8], nanowires [9], nanobelts [10], nanorods [11], mesoporous and microporous structures [12][13], and hollow nanospheres [14], have been synthesized by a variety of methods such as sol-gel method, chemistry precipitation method and hydrothermal method.…”

General fabrication and enhanced VOC gas-sensing properties of hierarchically porous metal oxides

“…On one hand, the addition of Au nanoparticles can lead to the formation of a rich active center, thus it is benecial for enhancing gas adsorption and increasing the concentration of the reaction. 31 Meanwhile, adding Au nanoparticles can also reduce the reaction activation energy and increase the reaction rate. 32 On the other hand, Au at the surface of the metal will participate in the oxygen adsorption reaction.…”