Current study reports a rapid one-pot non-hydrolytic condition in the synthesis of Sn O2QDs nanopowder using tin(II) stearate(Sn(St)2) as environmentally-benign organometallic precursor,which is an unprecedentedly emp...Current study reports a rapid one-pot non-hydrolytic condition in the synthesis of Sn O2QDs nanopowder using tin(II) stearate(Sn(St)2) as environmentally-benign organometallic precursor,which is an unprecedentedly employed-compound in preceding Sn O2nanopowder productions.The as-synthesized Sn O2QDs that are hydrophobic can be easily transferred from organic solvent to aqueous solution through a robust ligand exchange method.The stearate-capping ligands on the surface of QDs can be replaced by beta-cyclodextrin(β-CD) and eventually render the QDs highly water soluble,which ultimately make it exhibit bi-functionality for different liquid medium applications.Structural characterizations reveal that the bi-functional QDs are indeed well-matched with the standard rutile Sn O2cassiterite phase without the presence of any impurities.The QDs can be interchangeably used as photocatalyst for both aqueous and non-aqueous phase,where it shows significant enhancement of hydrogen gas production as compared to that of commercial Sn O2nanopowder.展开更多
SnO2 and Sb-doped SnO2 particles were synthesized using the polymeric precursor method with different Sn salt precursors： SnCl2.2H2O, SnCl4.5H20, or Sn citrate. Sb2O3 was used as the precursor of Sb, and the molar ra...SnO2 and Sb-doped SnO2 particles were synthesized using the polymeric precursor method with different Sn salt precursors： SnCl2.2H2O, SnCl4.5H20, or Sn citrate. Sb2O3 was used as the precursor of Sb, and the molar ratio of nsn：nsb was held constant. FTIR and TGA/DTA were used to examine the influence of the Sn precursor on the formation and thermal decomposition of the Sn and Sn-Sb complexes. The calcination products obtained from heating the Sn and Sn-Sb complexes at 500℃ in air were analyzed using XRD and TEM analysis. The results revealed that the SnO2 and Sb-doped SnO2 formation temperatures depended on the nature of the Sn precursor. The calcination products were found to be SnO2 and Sb-doped SnO2 particles, which crystallized in a tetragonal cassiterite structure with a highly preferred （110） planar orientation. The Sn precursor and the presence of Sb in the SnO2 matrix strongly influenced the crystallinity and lattice parameters.展开更多
According to the principle that fiber-like arrangement of reinforcing particles SnO2 paralleling to the direction of current is propitious to the electrical and mechanical performance of the electrical contact materia...According to the principle that fiber-like arrangement of reinforcing particles SnO2 paralleling to the direction of current is propitious to the electrical and mechanical performance of the electrical contact materials, we proposed and reported a novel precursor route used to prepare Ag/SnO2 electrical contact material with fiberlike arrangement of reinforcing nanoparticles. The mechanism for the formation of fiber-like arrangement of reinforcing nanoparticles in Ag/SnO2 electrical contact material was also discussed. The as-prepared samples were characterized by means of scanning electron microscope (SEM),optical microscope (OM),energy-dispersive X-ray spectroscopy (EDX),MHV2000 microhardness test,and double bridge tester. The analysis showed that the as-prepared Ag/SnO2 electrical contact material with fiber-like arrangement of reinforcing nanoparticles exhibits a high elongation of 24 %,a particularly low electrical resistivity of 2.08 μΩ· cm,and low arcing energy,and thus has considerable technical,economical and environmental benefits.展开更多
基金supported by e-Sciencefund(13-02-03-3093)Postgraduate Research Grant(PPP)(PG027-2013B)+4 种基金FRGS(FP038-2014B)MOHE-ERGS(ER002-2013A)funding from UMRG(RP007B-13AFR)High Impact Research Program(UM.C/625/1/HIR/079)HIR-MOHE(UM.C/625/1/HIR/MOHE/SC/06)
文摘Current study reports a rapid one-pot non-hydrolytic condition in the synthesis of Sn O2QDs nanopowder using tin(II) stearate(Sn(St)2) as environmentally-benign organometallic precursor,which is an unprecedentedly employed-compound in preceding Sn O2nanopowder productions.The as-synthesized Sn O2QDs that are hydrophobic can be easily transferred from organic solvent to aqueous solution through a robust ligand exchange method.The stearate-capping ligands on the surface of QDs can be replaced by beta-cyclodextrin(β-CD) and eventually render the QDs highly water soluble,which ultimately make it exhibit bi-functionality for different liquid medium applications.Structural characterizations reveal that the bi-functional QDs are indeed well-matched with the standard rutile Sn O2cassiterite phase without the presence of any impurities.The QDs can be interchangeably used as photocatalyst for both aqueous and non-aqueous phase,where it shows significant enhancement of hydrogen gas production as compared to that of commercial Sn O2nanopowder.
文摘SnO2 and Sb-doped SnO2 particles were synthesized using the polymeric precursor method with different Sn salt precursors： SnCl2.2H2O, SnCl4.5H20, or Sn citrate. Sb2O3 was used as the precursor of Sb, and the molar ratio of nsn：nsb was held constant. FTIR and TGA/DTA were used to examine the influence of the Sn precursor on the formation and thermal decomposition of the Sn and Sn-Sb complexes. The calcination products obtained from heating the Sn and Sn-Sb complexes at 500℃ in air were analyzed using XRD and TEM analysis. The results revealed that the SnO2 and Sb-doped SnO2 formation temperatures depended on the nature of the Sn precursor. The calcination products were found to be SnO2 and Sb-doped SnO2 particles, which crystallized in a tetragonal cassiterite structure with a highly preferred （110） planar orientation. The Sn precursor and the presence of Sb in the SnO2 matrix strongly influenced the crystallinity and lattice parameters.
基金National Major Scientific&Technological Achievement Transformation Project
文摘According to the principle that fiber-like arrangement of reinforcing particles SnO2 paralleling to the direction of current is propitious to the electrical and mechanical performance of the electrical contact materials, we proposed and reported a novel precursor route used to prepare Ag/SnO2 electrical contact material with fiberlike arrangement of reinforcing nanoparticles. The mechanism for the formation of fiber-like arrangement of reinforcing nanoparticles in Ag/SnO2 electrical contact material was also discussed. The as-prepared samples were characterized by means of scanning electron microscope (SEM),optical microscope (OM),energy-dispersive X-ray spectroscopy (EDX),MHV2000 microhardness test,and double bridge tester. The analysis showed that the as-prepared Ag/SnO2 electrical contact material with fiber-like arrangement of reinforcing nanoparticles exhibits a high elongation of 24 %,a particularly low electrical resistivity of 2.08 μΩ· cm,and low arcing energy,and thus has considerable technical,economical and environmental benefits.
