The microstructure revolution and mechanical properties of as-extruded and peak-aged Mg−6Zn−1Mn−4Sn−0.5Ca(ZMT614−0.5Ca)alloy were studied by OM,SEM,TEM,hardness testing and tensile testing.The results showed that the ...The microstructure revolution and mechanical properties of as-extruded and peak-aged Mg−6Zn−1Mn−4Sn−0.5Ca(ZMT614−0.5Ca)alloy were studied by OM,SEM,TEM,hardness testing and tensile testing.The results showed that the as-cast ZMT614−0.5Ca alloy mainly consisted of α-Mg,Mg−Zn and CaMgSn phase.The hot extrusion process effectively refined the microstructure and led to a completely dynamic recrystallized microstructure.The average grain size of as-extruded alloy was^4.85μm.After solution treatment,remained CaMgSn with high melting point played a significant role in pinning effect and impeding the migration of grain boundary.After aging treatment,peak-aged ZMT614−0.5Ca alloy exhibited a good combination of strength and ductility,with yield strength,ultimate tensile strength and elongation being 338 MPa,383 MPa and 7.5%,respectively.The yield strength of the alloy increased significantly by around 36%compared with that in as-extruded condition,which should be attributed to the precipitation strengthening of β'phase.展开更多
The Cu2ZnSnS4 thin film was prepared by a facile solution method without vacuum environment and toxic substance. The formation mechanism of the film was studied by transmission electron microscopy (TEM), X-ray diffrac...The Cu2ZnSnS4 thin film was prepared by a facile solution method without vacuum environment and toxic substance. The formation mechanism of the film was studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and Raman scattering measurements. Through cyclic voltammetry and photo-electricity tests, the electrocatalytic activity of the prepared film as the counter electrode of dye-sensitizedsolar cell was also studied. The results show that the mixed precursor solution mainly consists of Cu2SnS3 nanoparticles and Zn ions.After 550 °C annealing process on the precursor film prepared from the mixed solution, Cu2ZnSnS4 thin film is obtained. Besides, itis found that the prepared Cu2ZnSnS4 thin film has the electrocatalytic activity toward the redox reaction of I3?/I? and the dye-sensitized solar cell with the prepared Cu2ZnSnS4 thin film as the counter electrode achieves the efficiency of 1.09%.展开更多
Compound Zn2Sn0.8Ti0.2O4 was synthesized by a hydrothermal method in which SnCl4-5H2O,TiCl4,ZnCl2 and N2H4-H2O were used as reactants.The composite Zn2Sn0.8Ti0.2O4/C was then prepared through a carbothermic reduction ...Compound Zn2Sn0.8Ti0.2O4 was synthesized by a hydrothermal method in which SnCl4-5H2O,TiCl4,ZnCl2 and N2H4-H2O were used as reactants.The composite Zn2Sn0.8Ti0.2O4/C was then prepared through a carbothermic reduction process using the as-prepared Zn2Sn0.8Ti0.2O4 and glucose as reactants.The structure,morphology and electrochemical properties of the as-prepared products were investigated by XRD,XPS,TEM and electrochemical measurements.In addition,electrochemical Li insertion/extraction in composite Zn2Sn0.8Ti0.2O4/C were examined by ex situ XRD and SEM.The first discharge capacity of Zn2SnO4 is about 1670.8 mA-h/g,with a capacity retain of 342.7 mA-h/g in the 40th cycle at a constant current density of 100 mA/g in the voltage range of 0.05-3.0 V.Comparing with the Zn2SnO4,some improved electrochemical properties are obtained for Zn2Sn0.8Ti0.2O4,Zn2SnO4/C and Zn2Sn0.8Ti0.2O4/C.The composite Zn2Sn0.8Ti0.2O4/C shows the best electrochemical properties,and its first discharge capacity is about 1530.0 mA-h/g,with a capacity retain of 479.1 mA-h/g the 100th cycle.展开更多
基金Project(2016YFB0301101)supported by the National Key Research and Development Program of ChinaProjects(51571040,U1764253,51531002)supported by the National Natural Science Foundation of China。
文摘The microstructure revolution and mechanical properties of as-extruded and peak-aged Mg−6Zn−1Mn−4Sn−0.5Ca(ZMT614−0.5Ca)alloy were studied by OM,SEM,TEM,hardness testing and tensile testing.The results showed that the as-cast ZMT614−0.5Ca alloy mainly consisted of α-Mg,Mg−Zn and CaMgSn phase.The hot extrusion process effectively refined the microstructure and led to a completely dynamic recrystallized microstructure.The average grain size of as-extruded alloy was^4.85μm.After solution treatment,remained CaMgSn with high melting point played a significant role in pinning effect and impeding the migration of grain boundary.After aging treatment,peak-aged ZMT614−0.5Ca alloy exhibited a good combination of strength and ductility,with yield strength,ultimate tensile strength and elongation being 338 MPa,383 MPa and 7.5%,respectively.The yield strength of the alloy increased significantly by around 36%compared with that in as-extruded condition,which should be attributed to the precipitation strengthening of β'phase.
基金Projects(51204214,51272292,51222403)supported by the National Natural Science Foundation of China
文摘The Cu2ZnSnS4 thin film was prepared by a facile solution method without vacuum environment and toxic substance. The formation mechanism of the film was studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and Raman scattering measurements. Through cyclic voltammetry and photo-electricity tests, the electrocatalytic activity of the prepared film as the counter electrode of dye-sensitizedsolar cell was also studied. The results show that the mixed precursor solution mainly consists of Cu2SnS3 nanoparticles and Zn ions.After 550 °C annealing process on the precursor film prepared from the mixed solution, Cu2ZnSnS4 thin film is obtained. Besides, itis found that the prepared Cu2ZnSnS4 thin film has the electrocatalytic activity toward the redox reaction of I3?/I? and the dye-sensitized solar cell with the prepared Cu2ZnSnS4 thin film as the counter electrode achieves the efficiency of 1.09%.
基金Project (51004028) supported by the National Natural Science Foundation of China
文摘Compound Zn2Sn0.8Ti0.2O4 was synthesized by a hydrothermal method in which SnCl4-5H2O,TiCl4,ZnCl2 and N2H4-H2O were used as reactants.The composite Zn2Sn0.8Ti0.2O4/C was then prepared through a carbothermic reduction process using the as-prepared Zn2Sn0.8Ti0.2O4 and glucose as reactants.The structure,morphology and electrochemical properties of the as-prepared products were investigated by XRD,XPS,TEM and electrochemical measurements.In addition,electrochemical Li insertion/extraction in composite Zn2Sn0.8Ti0.2O4/C were examined by ex situ XRD and SEM.The first discharge capacity of Zn2SnO4 is about 1670.8 mA-h/g,with a capacity retain of 342.7 mA-h/g in the 40th cycle at a constant current density of 100 mA/g in the voltage range of 0.05-3.0 V.Comparing with the Zn2SnO4,some improved electrochemical properties are obtained for Zn2Sn0.8Ti0.2O4,Zn2SnO4/C and Zn2Sn0.8Ti0.2O4/C.The composite Zn2Sn0.8Ti0.2O4/C shows the best electrochemical properties,and its first discharge capacity is about 1530.0 mA-h/g,with a capacity retain of 479.1 mA-h/g the 100th cycle.
