Nanocomposites composed of SnO2 and CuO were prepared by hydrothermal method. The microstructures of obtained SnO2-CuO powders were characterized by X-ray diffraction, scanning electron microscopy, transmission electr...Nanocomposites composed of SnO2 and CuO were prepared by hydrothermal method. The microstructures of obtained SnO2-CuO powders were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and nitrogen adsorption-desorption test. The results show that the nanocomposites exhibited coral-like nanostructure, and the average crystalline size of SnO2 was 12 nm. The specific surface area of the four samples, SnO2- 0.2CuO, SnO2-0.5CuO, SnO2-1.0CuO and SnO2-2.0CuO are 72.97, 58.77, 49.72 and 54.95 m2/g, respectively. The gas sensing performance of the four samples to ethanol, formaldehyde and H2S was studied. The sensor of SnOa-0.5CuO exhibited high response to hydrogen sulfide （4173 to 10 ppm H2S, where ppm represent 10-6）, and low response to ethanol and formaldehyde. The good selectivity exhibited that the SnO2-0.5CuO nanocomposite can be a promising candidate for highly sensitive and selective gas-sensing material to H2S.展开更多
In this work,via a facile solvothermal route,we synthesized an anode material for lithium ion batteries（LIBs）—SnS2 nanoparticle/graphene（SnS2 NP/GNs） nanocomposite.The nanocomposite consists of SnS2nanoparticles ...In this work,via a facile solvothermal route,we synthesized an anode material for lithium ion batteries（LIBs）—SnS2 nanoparticle/graphene（SnS2 NP/GNs） nanocomposite.The nanocomposite consists of SnS2nanoparticles with an average diameter of 4 nm and graphene nanosheets without restacking.The SnS2 nanoparticles are firmly anchored on the graphene nanosheets.As an anode material for LIBs,the nanocomposite exhibits good Li storage performance especially high rate performance.At the high current rate of 5,10,and 20 A/g,the nanocomposite delivered high capacities of 525,443,and 378 mAh/g,respectively.The good conductivity of the graphene nanosheets and the small particle size of SnS2contribute to the electrochemical performance of SnS2 NP/GNs.展开更多
Europium doped ZnO/SnO2 nanocomposite phosphors were synthesized via room temperature co-precipitation method. In this work structural changes, optical properties and the associated photoluminescence response were inv...Europium doped ZnO/SnO2 nanocomposite phosphors were synthesized via room temperature co-precipitation method. In this work structural changes, optical properties and the associated photoluminescence response were investigated for different compositions of ZnO and SnO2 activated with Eu3＋ ions. The prepared samples were systematically characterized by means of X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR）, field emission scanning electron microscopy for obtaining the structural information about the prepared materials. Diffuse reflectance （DR） UV-Vis spectrometer and photoluminescence （PL） spectroscopy technique were employed for studying the optical properties of prepared materials. XRD results confirmed the presence of both phases, hexagonal ZnO as well as tetragonal SnO2 simultaneously and further using Debye Scherrer＇s and Hall-Williamson relations, crystallite size were estimated and it was found to be in the range of 8-14 nm. The FTIR studies revealed the presence of different stretching and bending modes of Zn-O and Sn-O with an additional stretching and bending vibration of absorbed water （O-H） molecules. FESEM images suggested that the particle size lied in the range of 50 to 70 nm, which were almost spherical in shapes. A long range multi colour emission from blue to red region was observed for the 320 nm excitation wavelength. The observed emission involved sharp emission due to 5D0→7F1 transition that corresponded to the magnetic dipole transition. The study showed that the Eu3＋ doped nanocomposite was more suitable material than singly Eu3＋ doped ZnO and Eu3＋ doped SnO2 with enhanced opto-eleetronic and luminescence properties and potential applications in display devices.展开更多
Heterostructure photocatalysts with a built-in electric field have become one of the most promising strategies to enhance photogenerated electron-hole pair separation. However, close contact between the two active com...Heterostructure photocatalysts with a built-in electric field have become one of the most promising strategies to enhance photogenerated electron-hole pair separation. However, close contact between the two active components of heterogeneous photocatalysts remains a problem. Herein, the in-situ fabrication of an SnO2/SnS2 heterostructure photocatalyst was performed;the structure showed enhanced photocatalytic performance resulting from the tight-contact heterostructures. The results of photoelectrochemical measurements further verified that a tight-contact heterostructure improved the separation of photogenerated electron-hole pairs. The results of EIS Bode plots also demonstrated that such in-situ fabricated SnO2/SnS2 samples exhibited the longest carrier lifetime(41.6 μs) owing to the intimate interface of SnO2/SnS2 heterostructures.展开更多
Increasing attention has been focused on potassium ion batteries(KIBs) as promising energy-sto rage system(ESS) owing to the abundance and low-cost of potassium resources.Here,SnS2/SnO2 hete rostructures were successf...Increasing attention has been focused on potassium ion batteries(KIBs) as promising energy-sto rage system(ESS) owing to the abundance and low-cost of potassium resources.Here,SnS2/SnO2 hete rostructures were successfully fixed onto stainless steel mesh(SnS2/SnO2/SSM) through a facile two-step hydrothermal method and used as anodes for KIBs.Due to the advantages of SnS2/SnO2 heterostructures and good conductivity of SSM substrate,the SnS2/SnO2/SSM anodes display enhanced electrochemical performance.The SnS2/SnO2/SSM anodes deliver specific capacity of 394 mA h g^-1 at 50 mA g^-1 over 100 cycles,better than SnO2/SSM.Even at 500 mA g^-1 after 250 cycles,high capacity of 155 mA h g^-1 can still be obtained.展开更多
Ternary nanocomposites of CuxZnySnzS(x+y+z)are considered as an emerging potential candidate as electrode materials for energy storage devices due to the considerable interlayer spaces and tunnels in its crystal struc...Ternary nanocomposites of CuxZnySnzS(x+y+z)are considered as an emerging potential candidate as electrode materials for energy storage devices due to the considerable interlayer spaces and tunnels in its crystal structures with excellent conducting ability.Recently,this nanocomposite used as anode material for Li-ion battery has been reported,but there is lim让ed research on让s application in supercapacitors which is considered a complementary energy storage device to battery.In this work,flower-like Cu5Sn2S7/ZnS and pristine Cu5Sn2S7 nanocomposite were prepared via a facile hydrothermal method.The electrochemical tests showed that the Cu5Sn2S7/ZnS nanocomposite exhibited better performance than pristine Cu5Zn2S7,suggesting that the existence of ZnS could significantly enhance the electrochemical performance of Cu5Sn2S7,with the good capacitance of 200 F/g at the current density of 1 A/g.Furthermore 170 F/g was obtained at the large current density of 10 A/g.Supercapacitors demonstrated energy density of 11.08 Wh/kg with power density 461 W/kg or 9.67 Wh/kg at power density of 4615 W/kg.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financially supported by the National Natural Science Foundation of China (No. 51072141)the scientific research projects of Education Department of Hubei province (D20141503)the President Foundation of Wuhan Institute of Technology (No. 2014029)
文摘Nanocomposites composed of SnO2 and CuO were prepared by hydrothermal method. The microstructures of obtained SnO2-CuO powders were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and nitrogen adsorption-desorption test. The results show that the nanocomposites exhibited coral-like nanostructure, and the average crystalline size of SnO2 was 12 nm. The specific surface area of the four samples, SnO2- 0.2CuO, SnO2-0.5CuO, SnO2-1.0CuO and SnO2-2.0CuO are 72.97, 58.77, 49.72 and 54.95 m2/g, respectively. The gas sensing performance of the four samples to ethanol, formaldehyde and H2S was studied. The sensor of SnOa-0.5CuO exhibited high response to hydrogen sulfide （4173 to 10 ppm H2S, where ppm represent 10-6）, and low response to ethanol and formaldehyde. The good selectivity exhibited that the SnO2-0.5CuO nanocomposite can be a promising candidate for highly sensitive and selective gas-sensing material to H2S.
基金financially supported by the National Natural Science Foundation of China (No. 21475085)the key scientific research project of high schools in Henan Province (Nos. 16A430025 & 17A480009)
文摘In this work,via a facile solvothermal route,we synthesized an anode material for lithium ion batteries（LIBs）—SnS2 nanoparticle/graphene（SnS2 NP/GNs） nanocomposite.The nanocomposite consists of SnS2nanoparticles with an average diameter of 4 nm and graphene nanosheets without restacking.The SnS2 nanoparticles are firmly anchored on the graphene nanosheets.As an anode material for LIBs,the nanocomposite exhibits good Li storage performance especially high rate performance.At the high current rate of 5,10,and 20 A/g,the nanocomposite delivered high capacities of 525,443,and 378 mAh/g,respectively.The good conductivity of the graphene nanosheets and the small particle size of SnS2contribute to the electrochemical performance of SnS2 NP/GNs.
基金supported by ISM research scholars funding by Government of India
文摘Europium doped ZnO/SnO2 nanocomposite phosphors were synthesized via room temperature co-precipitation method. In this work structural changes, optical properties and the associated photoluminescence response were investigated for different compositions of ZnO and SnO2 activated with Eu3＋ ions. The prepared samples were systematically characterized by means of X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR）, field emission scanning electron microscopy for obtaining the structural information about the prepared materials. Diffuse reflectance （DR） UV-Vis spectrometer and photoluminescence （PL） spectroscopy technique were employed for studying the optical properties of prepared materials. XRD results confirmed the presence of both phases, hexagonal ZnO as well as tetragonal SnO2 simultaneously and further using Debye Scherrer＇s and Hall-Williamson relations, crystallite size were estimated and it was found to be in the range of 8-14 nm. The FTIR studies revealed the presence of different stretching and bending modes of Zn-O and Sn-O with an additional stretching and bending vibration of absorbed water （O-H） molecules. FESEM images suggested that the particle size lied in the range of 50 to 70 nm, which were almost spherical in shapes. A long range multi colour emission from blue to red region was observed for the 320 nm excitation wavelength. The observed emission involved sharp emission due to 5D0→7F1 transition that corresponded to the magnetic dipole transition. The study showed that the Eu3＋ doped nanocomposite was more suitable material than singly Eu3＋ doped ZnO and Eu3＋ doped SnO2 with enhanced opto-eleetronic and luminescence properties and potential applications in display devices.
文摘Heterostructure photocatalysts with a built-in electric field have become one of the most promising strategies to enhance photogenerated electron-hole pair separation. However, close contact between the two active components of heterogeneous photocatalysts remains a problem. Herein, the in-situ fabrication of an SnO2/SnS2 heterostructure photocatalyst was performed;the structure showed enhanced photocatalytic performance resulting from the tight-contact heterostructures. The results of photoelectrochemical measurements further verified that a tight-contact heterostructure improved the separation of photogenerated electron-hole pairs. The results of EIS Bode plots also demonstrated that such in-situ fabricated SnO2/SnS2 samples exhibited the longest carrier lifetime(41.6 μs) owing to the intimate interface of SnO2/SnS2 heterostructures.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51704188,51464020,5170219961705125 and 51802181)the research starting foundation from Shaanxi University of Science and Technology(No.2018GBJ-04)。
文摘Increasing attention has been focused on potassium ion batteries(KIBs) as promising energy-sto rage system(ESS) owing to the abundance and low-cost of potassium resources.Here,SnS2/SnO2 hete rostructures were successfully fixed onto stainless steel mesh(SnS2/SnO2/SSM) through a facile two-step hydrothermal method and used as anodes for KIBs.Due to the advantages of SnS2/SnO2 heterostructures and good conductivity of SSM substrate,the SnS2/SnO2/SSM anodes display enhanced electrochemical performance.The SnS2/SnO2/SSM anodes deliver specific capacity of 394 mA h g^-1 at 50 mA g^-1 over 100 cycles,better than SnO2/SSM.Even at 500 mA g^-1 after 250 cycles,high capacity of 155 mA h g^-1 can still be obtained.
基金the support via Postgraduate Research Award of Queensland University of Technology(QUTPRA)
文摘Ternary nanocomposites of CuxZnySnzS(x+y+z)are considered as an emerging potential candidate as electrode materials for energy storage devices due to the considerable interlayer spaces and tunnels in its crystal structures with excellent conducting ability.Recently,this nanocomposite used as anode material for Li-ion battery has been reported,but there is lim让ed research on让s application in supercapacitors which is considered a complementary energy storage device to battery.In this work,flower-like Cu5Sn2S7/ZnS and pristine Cu5Sn2S7 nanocomposite were prepared via a facile hydrothermal method.The electrochemical tests showed that the Cu5Sn2S7/ZnS nanocomposite exhibited better performance than pristine Cu5Zn2S7,suggesting that the existence of ZnS could significantly enhance the electrochemical performance of Cu5Sn2S7,with the good capacitance of 200 F/g at the current density of 1 A/g.Furthermore 170 F/g was obtained at the large current density of 10 A/g.Supercapacitors demonstrated energy density of 11.08 Wh/kg with power density 461 W/kg or 9.67 Wh/kg at power density of 4615 W/kg.
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.
