Highly porous materials have attracted intensive attention in the past decades due to their unique geometrical configuration, unusual structural features, and outstanding physicochemical properties, but the facile cre...Highly porous materials have attracted intensive attention in the past decades due to their unique geometrical configuration, unusual structural features, and outstanding physicochemical properties, but the facile creation of porous metal nanomaterias remains a formidable challenge. Most reports focused on using hard templates to create porous metal nanomaterials via sacrificing the templates. Herein, we have created a new class of porous PtPb/Pt nanocrystals(NCs)with well-defined morphology, composition and porosity through a facile chemical etching approach. Due to the highly open three-dimensional(3D) structure and alloy effect, the porous PtPb/Pt NCs exhibit enhanced performances towards polyhydric alcohol electrooxidations with the optimized porous Pt3Pb nanoplates exhibiting superior activities of 1.75 mA cm-2 and 1.19 A mgPt-1 for ethylene glycol oxidation reaction(EGOR) and of 1.46 m A cm-2 and 1.00 A mg-1Pt for glycerol oxidation reaction(GOR) that are much higher than the commercial Pt/C(0.34 mA cm-2 and 0.22 A mgPt-1 for EGOR, 0.30 mA cm-2 and 0.20 A mgPt-1for GOR). In addition, the porous Pt3Pb nanoplates can endure the long-term stability in EG and glycerol oxidation reactions with limited activity and structure change after 20,000 and 5,000 cycles,respectively, showing a highly promising class of porous Ptbased electrocatalysts for direct polyhydric alcohol fuel cells and beyond.展开更多
Various supported Pt-Pb bimetallic catalysts were prepared and applied for the catalytic conversion of nitrobenzene to p-aminophenol in the environmentally benign pressurized CO2/H2O system.Among the bimetallic cataly...Various supported Pt-Pb bimetallic catalysts were prepared and applied for the catalytic conversion of nitrobenzene to p-aminophenol in the environmentally benign pressurized CO2/H2O system.Among the bimetallic catalysts prepared,Pt-Pb/SiO2 is the best and nitrobenzene could be converted to paminophenol with a selectivity as high as 82% when the reaction was carried out using this catalyst at110 ℃ under 5 MPa CO2 and 0.2 MPa H2.展开更多
LaNiO3 (LNO) thin films were prepared on Pt(111) / Ti / SiO2 / Si substrate by metal-organic decomposition (MOD) method. Pb(Zr,Ti)O3 ferroelectric thin films and their compositionally graded thin films were prepared o...LaNiO3 (LNO) thin films were prepared on Pt(111) / Ti / SiO2 / Si substrate by metal-organic decomposition (MOD) method. Pb(Zr,Ti)O3 ferroelectric thin films and their compositionally graded thin films were prepared on LNO / Pt / Ti / SiO2 /Si substrates by Sol-gel method. The composition depth profile of a typical up-graded film was determined by using a combination of Auger Electron Spectroscopy (ASE) and Ar Ion Etching. The results confirm that the processing method produces graded composition changes. XRD analysis showed that the graded thin films possessed composite structure of tetragonal and rhombohedral. The dielectric constants of Up-graded and Down-graded thin films were higher than that of each thin film unit. The dielectric constants were 277 and 269 at 10 kHz, respectively. The loss tangents were 0.019 and 0.018 at 10 kHz, respectively. The Hysteresis loops showed that the remanent polarizations of graded thin films were higher than that of each thin film unit, but the coercive fields were smaller. The remanent polarizations of Up-graded and Down-graded thin films were 30.06 and 26.96 μC·cm-2, respectively. The coercive fields were 54.14, 54.23 kV·cm-1, respectively. The pyroelectric coefficients of Up-graded and Down-graded thin films were 4.62, 2.51×10-8 C·cm-2·K-1 at room temperature, respectively. They were higher than that of each thin film unit.展开更多
基金financially supported by the Ministry of Science and Technology (2016YFA0204100,2017YFA0208200)the National Natural Science Foundation of China (21571135)+4 种基金the Young Thousand Talented Programthe Natural Science Foundation of Jiangsu Higher Education Institutions (17KJB150032)the project of scientific and technologic infrastructure of Suzhou (SZS201708)start-up support from Soochow Universitythe Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘Highly porous materials have attracted intensive attention in the past decades due to their unique geometrical configuration, unusual structural features, and outstanding physicochemical properties, but the facile creation of porous metal nanomaterias remains a formidable challenge. Most reports focused on using hard templates to create porous metal nanomaterials via sacrificing the templates. Herein, we have created a new class of porous PtPb/Pt nanocrystals(NCs)with well-defined morphology, composition and porosity through a facile chemical etching approach. Due to the highly open three-dimensional(3D) structure and alloy effect, the porous PtPb/Pt NCs exhibit enhanced performances towards polyhydric alcohol electrooxidations with the optimized porous Pt3Pb nanoplates exhibiting superior activities of 1.75 mA cm-2 and 1.19 A mgPt-1 for ethylene glycol oxidation reaction(EGOR) and of 1.46 m A cm-2 and 1.00 A mg-1Pt for glycerol oxidation reaction(GOR) that are much higher than the commercial Pt/C(0.34 mA cm-2 and 0.22 A mgPt-1 for EGOR, 0.30 mA cm-2 and 0.20 A mgPt-1for GOR). In addition, the porous Pt3Pb nanoplates can endure the long-term stability in EG and glycerol oxidation reactions with limited activity and structure change after 20,000 and 5,000 cycles,respectively, showing a highly promising class of porous Ptbased electrocatalysts for direct polyhydric alcohol fuel cells and beyond.
文摘Various supported Pt-Pb bimetallic catalysts were prepared and applied for the catalytic conversion of nitrobenzene to p-aminophenol in the environmentally benign pressurized CO2/H2O system.Among the bimetallic catalysts prepared,Pt-Pb/SiO2 is the best and nitrobenzene could be converted to paminophenol with a selectivity as high as 82% when the reaction was carried out using this catalyst at110 ℃ under 5 MPa CO2 and 0.2 MPa H2.
文摘LaNiO3 (LNO) thin films were prepared on Pt(111) / Ti / SiO2 / Si substrate by metal-organic decomposition (MOD) method. Pb(Zr,Ti)O3 ferroelectric thin films and their compositionally graded thin films were prepared on LNO / Pt / Ti / SiO2 /Si substrates by Sol-gel method. The composition depth profile of a typical up-graded film was determined by using a combination of Auger Electron Spectroscopy (ASE) and Ar Ion Etching. The results confirm that the processing method produces graded composition changes. XRD analysis showed that the graded thin films possessed composite structure of tetragonal and rhombohedral. The dielectric constants of Up-graded and Down-graded thin films were higher than that of each thin film unit. The dielectric constants were 277 and 269 at 10 kHz, respectively. The loss tangents were 0.019 and 0.018 at 10 kHz, respectively. The Hysteresis loops showed that the remanent polarizations of graded thin films were higher than that of each thin film unit, but the coercive fields were smaller. The remanent polarizations of Up-graded and Down-graded thin films were 30.06 and 26.96 μC·cm-2, respectively. The coercive fields were 54.14, 54.23 kV·cm-1, respectively. The pyroelectric coefficients of Up-graded and Down-graded thin films were 4.62, 2.51×10-8 C·cm-2·K-1 at room temperature, respectively. They were higher than that of each thin film unit.
