Tin dioxide(SnO2) and La-doped(1%,5%,10% in mass ratio) SnO2 samples were prepared via a hydrothermal method. The as-prepared powders were characterized by X-ray diffraction(XRD) and scanning electron microscopy(SEM) ...Tin dioxide(SnO2) and La-doped(1%,5%,10% in mass ratio) SnO2 samples were prepared via a hydrothermal method. The as-prepared powders were characterized by X-ray diffraction(XRD) and scanning electron microscopy(SEM) . Results showed that the particle size of SnO2 decreased gradually with the increase of the doped La element. When used as anode materials of Li ion battery,the La-doped samples exhibited better cycling performance than the pure SnO2,and the cycling performance of the La-doped samples got better and better with the increase of the doped La. The better electrochemical performance of the doped material could be attributed to the doping of La element,which not only enabled SnO2 powders to have a good dispersivity but also reduced their particle size.展开更多
Elemental doping is an effective strategy to enhance photocatalytic activity and extend the light absorption range of single-component photocatalysts.In this work,a series of La-doped CeO2 nanorods(La-CeO2-x) wi...Elemental doping is an effective strategy to enhance photocatalytic activity and extend the light absorption range of single-component photocatalysts.In this work,a series of La-doped CeO2 nanorods(La-CeO2-x) with La content of 1 wt%-15 wt% are synthesized by a simple hydrothermal method and further used as photocatalyst for sulfamerazine(SMR) degradation.The prepared La-CeO2-x nanorods exhibit a great improvement in electron-hole pair migration and visible-light response due to the synergistic effect of abundant oxygen vacancies and heterogeneous elements(La).Consequently,La-CeO2-x exhibited excellent visible-light photocatalytic performances and chemical stability for SMR degradation,the La-CeO2-5 sample achieved the highest SMR degradation rate of 81%,which was 3.4 times higher than that of the original CeO2.Furthermore,three possible degradation pathways of SMR in La-CeO2 photocatalytic reactions were proposed by liquid chromatography-mass spectrometry technique.Finally,density functional theory calculations were carried out to provide an in-depth understanding of the structure-performance relationships.Considering its excellent properties and better photocatalytic performance,this study demonstrates that La doping in CeO2 is an effective way to increase oxygen vacancy and improve the photochemical properties of photocatalysts.展开更多
In this work,La-doped Mg-Ni multiphase alloys were prepared by resistance melting furnace(RMF)and then modified by high-energy ball milling(HEBM).The hydrolysis H2 generation kineticshermodynamics of prepared alloy...In this work,La-doped Mg-Ni multiphase alloys were prepared by resistance melting furnace(RMF)and then modified by high-energy ball milling(HEBM).The hydrolysis H2 generation kineticshermodynamics of prepared alloys in Na Cl solutions have been investigated with the help of nonlinear and linear fitting by Avrami-Erofeev and Arrhenius equations.Combining the microstructure information before and after hydrolysis and thermodynamics fitting results,the hydrolysis H2 generation mechanism based on nucleation&growth has been elaborated.The final H2 generation capacities of 0La,5La,10La and 15 La alloys are 677,653,641 and 770 m L·g-1H2 in 240 min at291 K,respectively.While,the final H2 generation capacities of HEBM 0La,5La,10La and 15 La alloys are 632,824,611 and 653 m L·g-1H2 in 20 min at 291 K,respectively.The as-cast 15La alloy and HEMB 5La alloy present the best H2 production rates and final H2 production capacities,especially the HEBM 5La can rapidly achieve high H2 generation capacity(670 and 824 m L·g-1H2 )at low temperature(291 K)within short time(5 and 20 min).The difference between the H2 generation capacities is mainly originated from the initial nucleation rate of Mg(OH)2 and the subsequent processes affected by the microstructures and phase compositions of the hydrolysis alloys.Relative low initial nucleation rate and fully growth of Mg(OH)2 nucleus are the premise of high H2 generation capacity due to the hydrolysis H2 generation process consisted by the nucleation,growth and contacting of Mg(OH)2 nucleus.To utilization H2 by designing solid state H2 generators using optimized Mg-based alloys is expected to be a feasible H2 generation strategy at the moment.展开更多
It is urgent to solve the problems of the dramatic volume expansion and pulverization of SnO_2 anodes during cycling process in battery systems. To address this issue, we design a hybrid structure of N-doped carbon fi...It is urgent to solve the problems of the dramatic volume expansion and pulverization of SnO_2 anodes during cycling process in battery systems. To address this issue, we design a hybrid structure of N-doped carbon fibers@SnO_2 nanoflowers(NC@SnO_2) to overcome it in this work. The hybrid NC@SnO_2 is synthesized through the hydrothermal growth of SnO_2 nanoflowers on the surface of N-doped carbon fibers obtained by electrospinning. The NC is introduced not only to provide a support framework in guiding the growth of the SnO_2 nanoflowers and prevent the flower-like structures from agglomeration, but also serve as a conductive network to accelerate electronic transmission along one-dimensional structure effectively. When the hybrid NC@SnO_2 was served as anode, it exhibits a high discharge capacity of 750 Ah g-1 at 1 A g-1 after 100 cycles in Li-ion battery and 270 mAh g-1 at 100 mA g-1 for 100 cycles in Na-ion battery, respectively.展开更多
Recent progress in nanoscience and nanotechnology creates new opportunities in the design of novel SnO2 nanomaterials for photocatalysis and photoelectrochemical. Herein, we firstly highlight a facile method to prepar...Recent progress in nanoscience and nanotechnology creates new opportunities in the design of novel SnO2 nanomaterials for photocatalysis and photoelectrochemical. Herein, we firstly highlight a facile method to prepare threedimensional porous networks of ultra-long SnO2 nanotubes through the single capillary electrospinning technique.Compared with the traditional SnO2 nanofibers, the as-obtained three-dimensional porous networks show enhancement of photocurrent and photocatalytic activity, which could be ascribed to its improved light-harvesting efficiency and high separation efficiency of photogenerated electron–hole pairs. Besides, the synthesis route delivered three-dimensional sheets on the basis of interwoven nanofibrous networks, which can be readily recycled for the desirable circular application of a potent photocatalyst system.展开更多
基金Project supported by the National Natural Science Foundation of China (20871107)Henan Outstanding Youth Science Fund (0612002700)the Natural Science Foundation of the Education Department of Henan Province (2009A150031)
摘要Tin dioxide(SnO2) and La-doped(1%,5%,10% in mass ratio) SnO2 samples were prepared via a hydrothermal method. The as-prepared powders were characterized by X-ray diffraction(XRD) and scanning electron microscopy(SEM) . Results showed that the particle size of SnO2 decreased gradually with the increase of the doped La element. When used as anode materials of Li ion battery,the La-doped samples exhibited better cycling performance than the pure SnO2,and the cycling performance of the La-doped samples got better and better with the increase of the doped La. The better electrochemical performance of the doped material could be attributed to the doping of La element,which not only enabled SnO2 powders to have a good dispersivity but also reduced their particle size.
基金financially supported by the National Natural Science Foundation of China (No.52300206)the Natural Science Foundation of Jiangsu Province (No.BK20230705)+3 种基金the Industry-University Research Cooperation Project of Jiangsu Province,China (No.BY20221227)Natural Science Foundation of Jiangsu Higher Education Institutions of China (No.22KJB610014)the Talent-Recruiting Program of Nanjing Institute of Technology (No.YKJ202124)the Open Fund of Advanced Industrial Technology Research Institute,Nanjing Institute of Technology (No. XJY202110)。
摘要Elemental doping is an effective strategy to enhance photocatalytic activity and extend the light absorption range of single-component photocatalysts.In this work,a series of La-doped CeO2 nanorods(La-CeO2-x) with La content of 1 wt%-15 wt% are synthesized by a simple hydrothermal method and further used as photocatalyst for sulfamerazine(SMR) degradation.The prepared La-CeO2-x nanorods exhibit a great improvement in electron-hole pair migration and visible-light response due to the synergistic effect of abundant oxygen vacancies and heterogeneous elements(La).Consequently,La-CeO2-x exhibited excellent visible-light photocatalytic performances and chemical stability for SMR degradation,the La-CeO2-5 sample achieved the highest SMR degradation rate of 81%,which was 3.4 times higher than that of the original CeO2.Furthermore,three possible degradation pathways of SMR in La-CeO2 photocatalytic reactions were proposed by liquid chromatography-mass spectrometry technique.Finally,density functional theory calculations were carried out to provide an in-depth understanding of the structure-performance relationships.Considering its excellent properties and better photocatalytic performance,this study demonstrates that La doping in CeO2 is an effective way to increase oxygen vacancy and improve the photochemical properties of photocatalysts.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.51704188,51702199,61705125,51802181)the State Key Laboratory of Solidification Processing in NWPU(Grant No.SKLSP201809)+2 种基金Natural Science Foundation of Shaanxi Province(Grant No.2019JQ-099)Research Starting Foundation from Shaanxi University of Science and Technology(Grant No.2016GBJ-04)the financial support of China Scholarship Council(Grant No.201808610089)。
摘要In this work,La-doped Mg-Ni multiphase alloys were prepared by resistance melting furnace(RMF)and then modified by high-energy ball milling(HEBM).The hydrolysis H2 generation kineticshermodynamics of prepared alloys in Na Cl solutions have been investigated with the help of nonlinear and linear fitting by Avrami-Erofeev and Arrhenius equations.Combining the microstructure information before and after hydrolysis and thermodynamics fitting results,the hydrolysis H2 generation mechanism based on nucleation&growth has been elaborated.The final H2 generation capacities of 0La,5La,10La and 15 La alloys are 677,653,641 and 770 m L·g-1H2 in 240 min at291 K,respectively.While,the final H2 generation capacities of HEBM 0La,5La,10La and 15 La alloys are 632,824,611 and 653 m L·g-1H2 in 20 min at 291 K,respectively.The as-cast 15La alloy and HEMB 5La alloy present the best H2 production rates and final H2 production capacities,especially the HEBM 5La can rapidly achieve high H2 generation capacity(670 and 824 m L·g-1H2 )at low temperature(291 K)within short time(5 and 20 min).The difference between the H2 generation capacities is mainly originated from the initial nucleation rate of Mg(OH)2 and the subsequent processes affected by the microstructures and phase compositions of the hydrolysis alloys.Relative low initial nucleation rate and fully growth of Mg(OH)2 nucleus are the premise of high H2 generation capacity due to the hydrolysis H2 generation process consisted by the nucleation,growth and contacting of Mg(OH)2 nucleus.To utilization H2 by designing solid state H2 generators using optimized Mg-based alloys is expected to be a feasible H2 generation strategy at the moment.
基金supported by the National Natural Science Foundation of China (Grant No. 51302079)the National Natural Science Foundation of Hunan Province (Grant No. 2017JJ1008)
摘要It is urgent to solve the problems of the dramatic volume expansion and pulverization of SnO_2 anodes during cycling process in battery systems. To address this issue, we design a hybrid structure of N-doped carbon fibers@SnO_2 nanoflowers(NC@SnO_2) to overcome it in this work. The hybrid NC@SnO_2 is synthesized through the hydrothermal growth of SnO_2 nanoflowers on the surface of N-doped carbon fibers obtained by electrospinning. The NC is introduced not only to provide a support framework in guiding the growth of the SnO_2 nanoflowers and prevent the flower-like structures from agglomeration, but also serve as a conductive network to accelerate electronic transmission along one-dimensional structure effectively. When the hybrid NC@SnO_2 was served as anode, it exhibits a high discharge capacity of 750 Ah g-1 at 1 A g-1 after 100 cycles in Li-ion battery and 270 mAh g-1 at 100 mA g-1 for 100 cycles in Na-ion battery, respectively.
基金supported financially by the National Natural Science Foundation of China (Nos. 51001091, 111174256, 91233101)the Fundamental Research Program from the Ministry of Science and Technology of China (No. 2014CB931704)Project funded by China Postdoctoral Science Foundation(No. 2014M560602)
摘要Recent progress in nanoscience and nanotechnology creates new opportunities in the design of novel SnO2 nanomaterials for photocatalysis and photoelectrochemical. Herein, we firstly highlight a facile method to prepare threedimensional porous networks of ultra-long SnO2 nanotubes through the single capillary electrospinning technique.Compared with the traditional SnO2 nanofibers, the as-obtained three-dimensional porous networks show enhancement of photocurrent and photocatalytic activity, which could be ascribed to its improved light-harvesting efficiency and high separation efficiency of photogenerated electron–hole pairs. Besides, the synthesis route delivered three-dimensional sheets on the basis of interwoven nanofibrous networks, which can be readily recycled for the desirable circular application of a potent photocatalyst system.