Ammonium metatungstate and cobalt nitrate were mixed at the molecular level in distilled water and then spray-decomposed to CoWO_4/WO_3 nanocomposite powder.The particle morphology,crystalline size,forming course,chem...Ammonium metatungstate and cobalt nitrate were mixed at the molecular level in distilled water and then spray-decomposed to CoWO_4/WO_3 nanocomposite powder.The particle morphology,crystalline size,forming course,chemical composition and phase structure of the powder were studied by SEM,TEM,DTA-TG,IR and XRD,respectively.Results show that the powder is homogeneous,spherical and nano-aggregated.展开更多
The heterostructured NiWO_(4)/WO_(3) nanotubes(Ni/W NTs)were synthesized by using a facile self-assembly method on the sacrificial polystyrene(PS)nanofibers templates.Then,the Pt-decorated NiWO_(4)/WO_(3)(Pt@Ni/W)comp...The heterostructured NiWO_(4)/WO_(3) nanotubes(Ni/W NTs)were synthesized by using a facile self-assembly method on the sacrificial polystyrene(PS)nanofibers templates.Then,the Pt-decorated NiWO_(4)/WO_(3)(Pt@Ni/W)composite NTs were obtained through using an ultrasonic mixing method.The experimental results display that the order of gas-sensing performance is Pt@Ni/W>Ni/W>WO_(3).The 2wt.%Pt@Ni/W-5 NTs indicate the supreme acetone-sensing response(R_(air)/R_(gas)=58.4 at 100×10^(−6))at 375℃,which is 10.6 and 1.53 times that of the WO_(3) and NiWO_(4)/WO_(3) NTs,respectively.Additionally,the 2wt.%Pt@Ni/W-5 NTs also exhibit the dramatically high selectivity toward acetone against ethanol,methanal,methanol,NH_(3) and toluene.The Pt-decorated Ni/W NTs show the excellent responsivity and stability toward acetone,which is ascribed to the construction of heterostructured NiWO_(4)/WO_(3) and the spill-over effect of Pt nanoparticles.展开更多
Gas sensors built with metal oxide semiconductors have attracted tremendous attention due to the growing demand for the detection of inflammable,explosive and toxic gases.Herein,to improve the sensing response,WO_(3) ...Gas sensors built with metal oxide semiconductors have attracted tremendous attention due to the growing demand for the detection of inflammable,explosive and toxic gases.Herein,to improve the sensing response,WO_(3) nanoparticles decorated with Ag and Pt bimetals(Ag and Pt/WO_(3) NPs)have been developed via combined hydrolysis and hydrothermal strategies.Such sensors prototypes show high response to acetone(Ra/Rg=250@100×10^(-6),140℃),which is 6.1 fold as high as that of the pristine WO_(3) NPs(Ra/Rg=41@100×10^(-6),140℃).Moreover,the recovery time of Ag and Pt/WO_(3) NPs was reduced from 138 to 13 s compared with that of the pristine WO_(3) NPs.The improved acetone sensing performance may be attributed to that the chemical and electronic sensitization of Ag and Pt to WO_(3) NPs increases adsorbed oxygen species,speeds up the reaction and thus boosts the sensing response.Our strategy that decoration of dual precious metals onto WO_(3) NPs improves the acetone sensing performance may be applied to the gas sensors of other sensing materials.展开更多
Localized surface plasmon resonance(LSPR)effects of nanoscale plasmonic metals/semiconductor composites have been extensively applied into visible light photocatalysis.However,Pt nanoparticles(NPs)with the visible LSP...Localized surface plasmon resonance(LSPR)effects of nanoscale plasmonic metals/semiconductor composites have been extensively applied into visible light photocatalysis.However,Pt nanoparticles(NPs)with the visible LSPR absorption maxima have rarely been used as a photosensitizer to facilitate photocatalytic reactions,especially the photocatalytic overall water splitting(POWS)reaction,presumably because they feature weak light absorption.Herein,we present that the increased plasmonic absorption and local field enhancement can be achieved in the wide visible range by exploiting the simulated and experimental expressions of Pt nanocuboctahedra and Pt cuboctahedra-WO_(3)nanohybrids(Pt-WO3).First,monodisperse Pt cuboctahedra with different sizes,a hierarchical WO_(3)nanoarchitecture composed of radially patterned WO_(3)nanopillars,and Pt-WO_(3)were systematically synthesized.Subsequently,visible plasmonic Pt-WO_(3)photocatalysts were employed in the POWS tests and exhibited the significant activity enhancement in the visible light region.The apparent quantum efficiency(AQE)of greater than 7%within the range of visible light has been achieved for the optimal Pt-WO3.展开更多
文摘Ammonium metatungstate and cobalt nitrate were mixed at the molecular level in distilled water and then spray-decomposed to CoWO_4/WO_3 nanocomposite powder.The particle morphology,crystalline size,forming course,chemical composition and phase structure of the powder were studied by SEM,TEM,DTA-TG,IR and XRD,respectively.Results show that the powder is homogeneous,spherical and nano-aggregated.
基金supported by the National Natural Science Foundation of China (Nos. 51772130, 51972145)。
文摘The heterostructured NiWO_(4)/WO_(3) nanotubes(Ni/W NTs)were synthesized by using a facile self-assembly method on the sacrificial polystyrene(PS)nanofibers templates.Then,the Pt-decorated NiWO_(4)/WO_(3)(Pt@Ni/W)composite NTs were obtained through using an ultrasonic mixing method.The experimental results display that the order of gas-sensing performance is Pt@Ni/W>Ni/W>WO_(3).The 2wt.%Pt@Ni/W-5 NTs indicate the supreme acetone-sensing response(R_(air)/R_(gas)=58.4 at 100×10^(−6))at 375℃,which is 10.6 and 1.53 times that of the WO_(3) and NiWO_(4)/WO_(3) NTs,respectively.Additionally,the 2wt.%Pt@Ni/W-5 NTs also exhibit the dramatically high selectivity toward acetone against ethanol,methanal,methanol,NH_(3) and toluene.The Pt-decorated Ni/W NTs show the excellent responsivity and stability toward acetone,which is ascribed to the construction of heterostructured NiWO_(4)/WO_(3) and the spill-over effect of Pt nanoparticles.
基金financially supported by the National Natural Science Foundation of China(No.52072184)the Fundamental Research Funds for the Central Universities,Nankai University(No.63201179)。
文摘Gas sensors built with metal oxide semiconductors have attracted tremendous attention due to the growing demand for the detection of inflammable,explosive and toxic gases.Herein,to improve the sensing response,WO_(3) nanoparticles decorated with Ag and Pt bimetals(Ag and Pt/WO_(3) NPs)have been developed via combined hydrolysis and hydrothermal strategies.Such sensors prototypes show high response to acetone(Ra/Rg=250@100×10^(-6),140℃),which is 6.1 fold as high as that of the pristine WO_(3) NPs(Ra/Rg=41@100×10^(-6),140℃).Moreover,the recovery time of Ag and Pt/WO_(3) NPs was reduced from 138 to 13 s compared with that of the pristine WO_(3) NPs.The improved acetone sensing performance may be attributed to that the chemical and electronic sensitization of Ag and Pt to WO_(3) NPs increases adsorbed oxygen species,speeds up the reaction and thus boosts the sensing response.Our strategy that decoration of dual precious metals onto WO_(3) NPs improves the acetone sensing performance may be applied to the gas sensors of other sensing materials.
基金supported by the Six Talent Peaks Project in Jiangsu Province(No.JNHB-043)the Research Fund of State Key Laboratory of Materials-Oriented Chemical Engineering(No.ZK201713).
文摘Localized surface plasmon resonance(LSPR)effects of nanoscale plasmonic metals/semiconductor composites have been extensively applied into visible light photocatalysis.However,Pt nanoparticles(NPs)with the visible LSPR absorption maxima have rarely been used as a photosensitizer to facilitate photocatalytic reactions,especially the photocatalytic overall water splitting(POWS)reaction,presumably because they feature weak light absorption.Herein,we present that the increased plasmonic absorption and local field enhancement can be achieved in the wide visible range by exploiting the simulated and experimental expressions of Pt nanocuboctahedra and Pt cuboctahedra-WO_(3)nanohybrids(Pt-WO3).First,monodisperse Pt cuboctahedra with different sizes,a hierarchical WO_(3)nanoarchitecture composed of radially patterned WO_(3)nanopillars,and Pt-WO_(3)were systematically synthesized.Subsequently,visible plasmonic Pt-WO_(3)photocatalysts were employed in the POWS tests and exhibited the significant activity enhancement in the visible light region.The apparent quantum efficiency(AQE)of greater than 7%within the range of visible light has been achieved for the optimal Pt-WO3.
