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Abstract: Pure ZnO nanoparticle and doped-ZnO nanoparticles with Sb, In, Bi, In–Sb and In–Bi, were prepared by the renovated hybrid induction and laser heating (HILH). The morphological characteristics, phase structure and chemical state of nanoparticles were characterized by TEM, XRD and XPS, respectively. The microstructure, electrical properties and gas-sensing characteristic of the thick film based on nanoparticles were investigated. It was found that the morphology of nanoparticles was influenced by the doping elements Sb, In and Bi. The doping of In, Sb and In–Sb markedly increased the conductivity of ZnO film and its sensitivity to benzene, toluene and xylene. The former was attributed to the substitution of Zn ions by In ions or/and Sb ions, which resulted in generating more free electrons; the latter was closely related to doped samples accommodating a higher density of chemisorbed oxygen. Bi- and In–Bi codoped ZnO films contained Bi2O3 phase, which resulted in their lower conductivities than that of undoped ZnO, but their optimum sensitivity temperature decreased. The response-recovery time of the films to benzene, toluene and xylene was less than 20s, except the films containing Sb displaying a longer recovery time. [Copyright &y& Elsevier]

Undoped and Sb-doped ZnO nanoparticles were successfully synthesized by vapor condensation method from pure Zn and Zn–Sb alloy with different mole ratios (50:1, 15:1 and 6:1) as raw materials in a flowing gas mixture of Ar+O2. The morphological characteristics, phase structure, composition and chemical state of nanoparticles were measured by TEM, HRTEM, XRD, EDX and XPS, respectively. The microstructures of thick films based on nanoparticles were investigated by SEM. The gas sensitivity of thick film based on Sb-doped ZnO nanoparticles to volatile organic compounds (VOCs), benzene, toluene, xylene, acetone and alcohol, as a function of temperature were measured, and compared to undoped ZnO thick film. After doping with Sb, the morphology of ZnO nanoparticles is modified from the needle-shape to the polygon; the gas sensitivity of the thick films is greatly improved, wherein the sensitivity of Sb-doped ZnO nanoparticles produced from alloy with Zn/Sb=15:1 is maximal and response-recovery time is short. The gas sensitivity of the ZnO-based nanoparticles maybe depended on the content and chemical state of Sb in the ZnO lattices. [Copyright &y& Elsevier]

The thick film of Zn–Sb–O was prepared by coating the paste of nanoparticles mixture (Sb2O3:ZnO=1:3) on the alumina substrate, followed by sintering at 500–900 °C for 2 h in air. The electrical resistance and gas-sensing properties to benzene, alcohol and acetone of Zn–Sb–O films were found to be dependent on the change of phase structure caused by sintering temperature. [Copyright &y& Elsevier]

Influence of the oxygen partial pressure (0.5×103 Pa to 4×103 Pa) on synthesis and characteristics of Sb2O3 nanoparticles evaporated from the pure antimony by means of hybrid induction and laser heating (HILH) method in a flowing Ar+O2 atmosphere has been systematically investigated using TEM, XRD, XPS, DSC, TGA, and UV-Vis-NIR spectrometry. The as-synthesized Sb2O3 nanopowder consists of small spherical particles with an average size of approximately 80 nm. As the oxygen partial pressure increases from 0.5×103 Pa to 4×103 Pa, the metallic Sb content in the nanopowder was decreased markedly. Both optical property at visible and all far infrared light scope ranging from 360 to 2500 nm and thermal characteristic of the Sb2O3 nanoparticles are strongly dependent on the oxygen partial pressure. [Copyright &y& Elsevier]

Sb2O3 nanoparticles with an average size of approximately 80 nm were synthesized by vapor condensation method. The characteristics were investigated by means of TEM, XRD, differential thermal analysis (DTA), X-ray photoelectron spectrometer (XPS) and Raman spectroscopy. The exothermic peak temperature for the nanopowder is lower than that of the micropowder, its reactive temperature span is narrower and oxidizing exothermic heat is larger due to the nano-sized effect. XPS analysis shows that a few amount of antimonies are still in metallic states as the interstitial antinomy atoms in the nanoparticles. The interstitial atoms may be mainly responsible for the red shifts (3–6.4 cm−1) of the characteristic peaks in the Raman spectrum. [Copyright &y& Elsevier]

Hexagonal Sb-doped zinc oxide (ZnO) nanoparticles with perfect wurtzite structure were synthesized by vapor condensation method from Zn–Sb alloy as the raw material in a flowing mixture gas atmosphere of Ar+O2. The synthesized powder has an average size of approximate 60 nm in a narrow distribution. X-ray photoelectron spectrometry (XPS) and energy-dispersive X-ray analysis (EDX) results clearly show that Sb element has been doped into the ZnO nanoparticles. The crystal growth of the ZnO nanoparticles could be controlled by the Sb element doped. Compared to the undoped ZnO nanoparticles, its optical reflectivity and electrical resistivity increase considerably. [Copyright &y& Elsevier]

Abstract: Spherical Sb/Sb2O3 composite nanoparticles ∼80nm in diameter were synthesized by innovated hybrid induction and laser heating (HILH). Under the irradiation of 80kV electronic beams for 3min, the aligned nanoparticles were welded into the Y-type nanorods, indicating their instability. Moreover, after annealed at ≥400°C for 1h in air, the Sb/Sb2O3 nanoparticles exhibit thermal instability. Their shape varies from the spherical nanoparticles, through the regular polygon nanoparticles, irregular polygon microparticles into the spear-like microparticles, as the annealing temperature increases from 400 to 600°C. Beyond 500°C, the Sb content inside them completely disappears. The metallic Sb inside the Sb/Sb2O3 nanoparticles is responsible for their instability. [Copyright &y& Elsevier]