Rapid thermal annealing effects on tin oxide nanowires prepared by vapor–liquid–solid technique

Abstract

Tin oxide nanowires have been grown on p-type silicon substrates using a gold-catalyst-assisted vapor-liquid-solid growth process. The nanowires were annealed in the presence of oxygen at 700 degrees C for different time intervals. The changes in material properties of the nanowires after annealing were investigated using various characterization techniques. Annealing improves the crystal quality of the nanowires as seen from Raman spectroscopy analysis. Photoluminescence (PL) data indicates a decrease in the oxygen vacancies and defects after annealing, affecting the luminescence from the nanowires. In addition, x-ray photoelectron spectroscopy (XPS) was used to obtain the changes in the tin and oxygen atomic concentrations before and after annealing, from which the stoichiometry was calculated.

Preliminary investigation on the modification of electronic properties in surface passivated SnO2 nanowires with Schottky contacts on being exposed to 137Cs γ-radiation

“…The UV peak is centered at 383 nm and is believed to be due to the V / state since it is assumed to be a very shallow donor. 7,8 However, the broad peak that is centered at 590 nm is due to the V þ 0 oxygen vacancy and indicates that the as grown nanowires lack the exposed bridging oxygen atoms. It can be further seen in Figure 5(a) that, as the radiation exposure duration increases from 3 to 6 min, both the UV and visible luminescence intensity due to the radiative recombination from the traps states increases.…”

“…Tin oxide nanowires were grown using the vaporliquid-solid (VLS) growth technique, 6,22 where the source consisted of stannous tin oxide (SnO) of 99.999% purity mixed with graphite in a weight ratio of 1:1 to carry out a carbothermal reduction process at a temperature of 880 C. 7,8 HR-TEM images of the nanowires were obtained using a JEOL JEM 3010 system, whereas low resolution images of the randomly assembled nanowires were obtained using a variable pressure Hitachi S-3000 N scanning electron microscope (SEM). Figure 1 Figure 1(b) further demonstrates the single crystalline nature of the nanowires.…”

Building one-dimensional oxide nanostructure arrays on conductive metal substrates for lithium-ion battery anodes

“…Various 1D oxide nanostructure array electrodes 3.1 SnO 2 nanorod/wire arrays As an important n-type semiconductor, SnO 2 has been regarded as a potential graphite substitute primarily owing to its high theoretical specific capacity ($781 mAh g À1 ) and safety. [67][68][69][70] More importantly, relatively low average working potential (<1.0 V) renders its superior practical value to other oxide anode materials. Thus, making 1D oriented nanostructure array of SnO 2 on metal substrate over a large area and further applying it as anode of battery are not only significant to fundamental study but also highly desirable for the exploration of novel electrode materials.…”

Defect induced optical bandgap narrowing in undoped SnO2 nanocrystals

“…6,8,14 Recently, we have demonstrated the existence of room temperature ferromagnetism due to high defect density in undoped SnO 2 nanoparticles prepared by solution combustion synthesis, which is a non-equilibrium method. 15 The sudden cooling of the product from high temperatures (>1000…”