The synthesis and selective gas sensing characteristics of SnO₂/α-Fe₂O₃hierarchical nanostructures

Abstract

SnO(2)/α-Fe(2)O(3) hierarchical nanostructures, in which the SnO(2) nanorods grow on the side surface of α-Fe(2)O(3) nanorods as multiple rows, were synthesized via a three-step process. The diameters and lengths of the SnO(2) nanorods are 6-15 nm and about 120 nm. The growth direction of SnO(2) nanorods is [001], significantly affected by that of α-Fe(2)O(3) nanorods. The hetero-nanostructures exhibit very good selectivity to ethanol. The sensing characteristics are related to the special heterojunction structures, confirmed by high-resolution transmission electron microscopy observation. Therefore, a heterojunction barrier controlled gas sensing mechanism is realized. Our results demonstrate that the hetero-nanostructures are promising materials for fabricating sensors and other complex devices.

Synthesis and magnetic properties of CdS/α-Fe2O3 hierarchical nanostructures

“…The crystal structures of the samples were determined by X-ray diffraction (XRD, D/max 2550V, Cu Kα radiation). nanorods in this work were obtained by the calcinations of β-FeOOH nanorods at 500℃ for 2.5 h. The morphology and size of β-FeOOH nanorods were depicted in other literature [33] . Curve 1 of Figure 1 shows Figure 2(a) is a typical SEM image of the as-synthesized α-Fe 2 O 3 nanorods.…”

“…It has been reported that EDA could coordinate with Cd ion to form chelating complexes, resulting in the decrease of the Cd ion concentration in the solution. It favors the formation of smaller CdS nanocrystals [33] . At the same time, the Cd chelating complexes are more likely to adsorb on the surface of other materials such as α-Fe 2 O 3 used in this work, thereby allow heterogeneous nucleation and growth to occur by a ligand exchange condensation reaction, with S ion released from thiourea [34] .…”

“…In recent years, great progress has been made in the synthesis of such nanocomposites [28][29][30][31][32][33][34] . Hierarchical ZnO nanostructures were synthesized by a vapor transport and condensation technique.…”

Synthesis of hierarchical SnO2 nanoflowers with enhanced acetic acid gas sensing properties

“…Therefore, the nanoscale assemblies, including nanoparticles [6], nanotubes [7], nanorods [8], nanosheets [9], nanocones [10] and hollow microspheres [11] are widely studied due to their various properties and potential applications [12][13][14][15][16][17][18]. As a multifunctional n-type semiconductor with a wide band gap (Eg = 3.6 eV), tin oxide (SnO 2 ) is regarded as an important functional material and extensively applied in various fields, such as in photocatalyst [19], gas sensors [20] and electrode materials [21].…”

One-pot synthesis of crystalline SnO2 nanoparticles and their low-temperature ethanol sensing characteristics

“…Nowadays, many techniques have been developed to decrease the size of SnO 2 , and improve their sensing performance [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] . Pang et al synthesized SnO 2 nanoparticles (NPs) adsorbed onto the surface of SrCO 3 NPs by a sonochemical method [4] .…”