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Synthesis of SiOC@C ceramic nanospheres with tunable electromagnetic wave absorption performance
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作者 Junjie Qian Dandan Ma +5 位作者 Xiaoling Zhou Huoming Liao Qingliang Shan Shaohua Wang Yongqing Wang Xiaojun Zeng 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2024年第9期1394-1408,共15页
SiOC-based ceramics are considered promising electromagnetic wave-absorbing materials because of their lightweight,high-temperature resistance,and heat insulation properties.Herein,SiOC@C ceramic nanospheres were prep... SiOC-based ceramics are considered promising electromagnetic wave-absorbing materials because of their lightweight,high-temperature resistance,and heat insulation properties.Herein,SiOC@C ceramic nanospheres were prepared using a liquid-phase method combined with a polymer-derived ceramic(PDC)method,followed by heat treatment in N_(2) and Ar atmospheres at different temperatures.The morphology,microstructure,phase composition,and electromagnetic wave absorption performance of the SiOC@C ceramic nanospheres were investigated in detail.The SiOC@C ceramic nanospheres obtained in the Ar atmosphere showed a minimum reflection loss(RL_(min))of−67.03 dB,whereas the SiOC@C ceramic nanospheres obtained in the N_(2) atmosphere exhibited an RLmin value of−63.76 dB.The outstanding electromagnetic wave absorption performance of the SiOC@C ceramic nanospheres was attributed to the synergistic effect between conductive loss,interfacial/defect polarization loss,multiple reflections,and scattering.Therefore,this research provides valuable insights into the design and fabrication of SiOC ceramic-based electromagnetic wave absorbers. 展开更多
关键词 SiOC ceramic nanospheres electromagnetic wave absorption performance polymer-derived ceramics(PDCs) free carbon
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Controllable synthesis of CdS nanospheres photoelectrode for photoelectrochemical water splitting
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作者 Yingpeng Xie Yi Sun +7 位作者 Renzheng Jiang Junhua Chang Yongqiang Yang Lili Zhang Chao Zhen Fei Han Enlei Zhang Guosheng Wang 《Resources Chemicals and Materials》 2024年第1期38-45,共8页
CdS nanospheres were grown on indium tin oxide(ITO)substrate using a hydrothermal method.The crystal structure,morphology and electronic structure of the samples synthesized were characterized in detail.The results co... CdS nanospheres were grown on indium tin oxide(ITO)substrate using a hydrothermal method.The crystal structure,morphology and electronic structure of the samples synthesized were characterized in detail.The results confirm that the crystallinity,size,crystal defects of the CdS nanospheres and the film thickness of CdS photoelectrodes can be tuned by varying the precursor Cd2+concentration.Combined with charge transfer dynamics analysis,it can be found that proper particle size and film thickness,as well as fewer defects,will result in better charge separation efficiency of the prepared CdS/ITO photoelectrodes,thereby exhibiting better photoelectrochemical performance for water splitting.The optimized CdS/ITO photoelectrode synthesized with a Cd2+concentration of 0.14 mol⋅L1 gave a photocurrent density of 5.10 mA⋅cm^(-2)at potential of 1.23 V versus the reversible hydrogen electrode(RHE),under a simulated solar illumination of 100 mW⋅cm^(-2). 展开更多
关键词 CdS nanospheres Crystal defects Film thickness PHOTOELECTRODES Water splitting
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Hollow Gradient-Structured Iron-Anchored Carbon Nanospheres for Enhanced Electromagnetic Wave Absorption 被引量:6
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作者 Cao Wu Jing Wang +14 位作者 Xiaohang Zhang Lixing Kang Xun Cao Yongyi Zhang Yutao Niu Yingying Yu Huili Fu Zongjie Shen Kunjie Wu Zhenzhong Yong Jingyun Zou Bin Wang Zhou Chen Zhengpeng Yang Qingwen Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第1期144-160,共17页
In the present paper,a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance.The inorganic-organic competitive coating strategy was employed,which c... In the present paper,a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance.The inorganic-organic competitive coating strategy was employed,which can effectively adjust the thermodynamic and kinetic reactions of iron ions during the solvothermal process.As a result,Fe nanoparticles can be gradually decreased from the inner side to the surface across the hollow carbon shell.The results reveal that it offers an outstanding reflection loss value in combination with broadband wave absorption and flexible adjustment ability,which is superior to other relative graded distribution structures and satisfied with the requirements of lightweight equipment.In addition,this work elucidates the intrinsic microwave regulation mechanism of the multiscale hybrid electromagnetic wave absorber.The excellent impedance matching and moderate dielectric parameters are exhibited to be the dominative factors for the promotion of microwave absorption performance of the optimized materials.This strategy to prepare gradient-distributed microwave absorbing materials initiates a new way for designing and fabricating wave absorber with excellent impedance matching property in practical applications. 展开更多
关键词 Gradient structures Carbon nanospheres Electromagnetic wave absorption Impedance matching
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Sulfur/nitrogen/oxygen tri-doped carbon nanospheres as an anode for potassium ion storage 被引量:3
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作者 Xiaoyan Chen Wang Zhou +2 位作者 Jilei Liu Yingpeng Wu Zhigang Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期338-347,I0009,共11页
Carbonaceous materials are considered as ideal anode for potassium ion batteries(PIBs)due to their abundant resources and stable physical and chemical properties.However,improvements of reversible capacity and cycle p... Carbonaceous materials are considered as ideal anode for potassium ion batteries(PIBs)due to their abundant resources and stable physical and chemical properties.However,improvements of reversible capacity and cycle performance are still needed,aiming to the practical application.Herein,S/N/O tridoped carbon(SNOC)nanospheres are prepared by in-situ vulcanized polybenzoxazine.The S/N/O tridoped carbon matrix provides abundant active sites for potassium ion adsorption and effectively improves potassium storage capacity.Moreover,the SNOC nanospheres possess large carbon interlayer spacing and high specific surface area,which broaden the diffusion pathway of potassium ions and accelerate the electron transfer speed,resulting in excellent rate performance.As an anode for PIBs,SNOC shows attractive rate performance(438.5 mA h g^(-1) at 50 mA g^(-1) and 174.5 mA h g^(-1) at2000 mA g^(-1)),ultra-high reversible capacity(397.4 mA h g^(-1) at 100 mA g^(-1) after 700 cycles)and ultra-long cycling life(218.9 mA h g^(-1) at 2000 mA g^(-1) after 7300 cycles,123.1 mA h g^(-1) at3000 mA g^(-1) after 16500 cycles and full cell runs for 4000 cycles).Density functional theory calculation confirms that S/N/O tri-doping enhances the adsorption and diffusion of potassium ions,and in-situ Fourier-transform infrared explores explored the potassium storage mechanism of SNOC. 展开更多
关键词 Potassium ion batteries S/N/O tri-doped Carbon nanospheres ANODE
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Rationally designed hollow carbon nanospheres decorated with S,P co-doped NiSe_(2) nanoparticles for high-performance potassium-ion and lithium-ion batteries 被引量:3
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作者 Jiajia Ye Zizhong Chen +4 位作者 Zhiqiang Zheng Zhanghua Fu Guanghao Gong Guang Xia Cheng Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第3期401-411,I0011,共12页
Hollow nanostructures with external shells and inner voids have been proved to greatly shorten the transport distance of ions/electrons and buffer volume change,especially for the large-sized potassium-ions in seconda... Hollow nanostructures with external shells and inner voids have been proved to greatly shorten the transport distance of ions/electrons and buffer volume change,especially for the large-sized potassium-ions in secondary batteries.In this work,hollow carbon(HC) nanospheres embedded with S,P co-doped NiSe_(2)nanoparticles are fabricated by "drop and dry" and "dissolving and precipitation" processes to form Ni(OH)2nanocrystals followed by annealing with S and P dopants to form nanoparticles.The resultant S,P-NiSe_(2)/HC composite exhibits excellent cyclic performance with 131.6 mA h g^(-1)at1000 mA g^(-1)after 3000 cycles for K^(+)storage and a capacity of 417.1 mA h g^(-1)at 1000 mA g^(-1)after1000 cycles for Li^(+)storage.K-ion full cells are assembled and deliver superior cycling stability with a ca pacity of 72.5 mA h g^(-1)at 200 mA g^(-1)after 500 cycles.The hollow carbon shell with excellent electrical conductivity effectively promotes the transporta tion and tolerates large volume variation for both K^(+)and Li^(+).Density functional theory calculations confirm that the S and P co-doping NiSe_(2) enables stronger adsorption of K^(+)ions and higher electrical conductivity that contributes to the improved electrochemical performance. 展开更多
关键词 S P co-doping NiSe_(2)nanoparticles Hollow carbon nanospheres Potassium-ion batteries Lithium-ion batteries
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Construction of phosphorus-doping with spontaneously developed selenium vacancies: Inducing superior ion-diffusion kinetics in hollow Cu_(2)Se@C nanospheres for efficient sodium storage
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作者 Xiaoqing Ma Yadong Li +4 位作者 Xiaojiang Long Hong-chuan Luo Chunping Xu Guangzhao Wang Wenxi Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期227-238,I0007,共13页
Achieving high-efficiency sodium storage in metal selenides is still severely constrained in consideration of their inferior electronic conductivity and inadequate Na^(+)insertion pathways and active sites.Heteroatom ... Achieving high-efficiency sodium storage in metal selenides is still severely constrained in consideration of their inferior electronic conductivity and inadequate Na^(+)insertion pathways and active sites.Heteroatom doping accompanied by spontaneously developed lattice defects can effectively tune electronic structure of metal selenides,which give a strong effect to motivate fast charge transfer and Na^(+)accessibility.Herein,we finely designed and successfully constructed a fascinating phosphorus-doped Cu_(2)Se@C hollow nanosphere with abundant vacancy defects(Cu_(2)P_(x)Se_(1-x)@C)through a combination strategy of selenization of Cu_(2)O nanosphere template,self-polymerization of dopamine,and subsequent phosphorization treatment.Such exquisite composite possesses enriched active sites,superior conductivity,and sufficient Na^(+)insertion channel,which enable much faster Na^(+)diffusion rates and more remarkable pseudocapacitive features,Satisfyingly,the Cu_(2)P_(x)Se_(1-x)@C composites manifest the supernormal sodium-storage capabilities,that is,a reversible capacity of 403.7 mA h g^(-1) at 1.0 A g^(-1) over 100 cycles,and an ultrastable cyclic lifespan over 1000 cycles at 20.0 A g^(-1) with a high capacity-retention of about249.7 mA h g^(-1).The phase transformation of the Cu_(2)P_(x)Se_(1-x)@C involving the intercalation of Na^(+)into Cu_(2)Se and the following conversion of NaCuSe to Cu and Na2Se were further demonstrated through a series of ex-situ characterization methods.DFT results demonstrate that the coexistence of phosphorusdoping and vacancy defects within Cu_(2)Se results in the reduction of Na^(+)adsorption energy from-1.47to-1.56 eV improving the conductivity of Cu_(2)Se to further accelerate fast Na^(+)mobility. 展开更多
关键词 Phosphorus-doping Selenium vacancies Hollow Cu_(2)Se@C nanospheres Anode Sodium storage
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Highly Conductive Proton Selectivity Membrane Enabled by Hollow Carbon Sieving Nanospheres for Energy Storage Devices
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作者 Kang Huang Shuhao Lin +7 位作者 Yu Xia Yongsheng Xia Feiyan Mu Yuqin Lu Hongyan Cao Yixing Wang Weihong Xing Zhi Xu 《Engineering》 SCIE EI CAS CSCD 2023年第9期69-78,共10页
Ion conductive membranes(ICMs)with highly conductive proton selectivity are of significant importance and greatly desired for energy storage devices.However,it is extremely challenging to construct fast proton-selecti... Ion conductive membranes(ICMs)with highly conductive proton selectivity are of significant importance and greatly desired for energy storage devices.However,it is extremely challenging to construct fast proton-selective transport channels in ICMs.Herein,a membrane with highly conductive proton selectivity was fabricated by incorporating porous carbon sieving nanospheres with a hollow structure(HCSNs)in a polymer matrix.Due to the precise ion sieving ability of the microporous carbon shells and the fast proton transport through their accessible internal cavities,this advanced membrane presented a proton conductivity(0.084 S·cm^(-1))superior to those of a commercial Nation 212(N212)membrane(0.033S·cm^(-1))and a pure polymer membrane(0.049 S·cm^(-1)).The corresponding proton selectivity of the membrane(6.68×10^(5) S·min·cm^(-3))was found to be enhanced by about 5.9-fold and 4.3-fold,respectively,compared with those of the N212 membrane(1.13×10^(5) S·min·cm^(-3))and the pure membrane(1.56×10^(5) S·min·cm^(-3)).Low-field nuclear magnetic resonance(LF-NMR)clearly revealed the fast protonselective transport channels enabled by the HCSNs in the polymeric membrane.The proposed membrane exhibited an outstanding energy efficiency(EE)of 84%and long-term stability over 1400 cycles with a0.065%capacity decay per cycle at 120 mA·cm^(-2) in a typical vanadium flow battery(VFB)system. 展开更多
关键词 Ion conductive membrane Hollow carbon sieving nanosphere Proton transport channel Flow battery
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Synthesis of Flower-like NaY(MoO4)2 and Optical Property of NaY(MoO4)2:Eu^3+ 被引量:1
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作者 张悠金 祝玮 +1 位作者 何红梅 郑傲 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第4期451-456,J0002,共7页
Flower-like NaY(MoO4)2 particles were synthesized through a microwave-assisted hydrother- mal process followed by a subsequent calcination process. The products were characterized by X-ray diffraction, X-ray photoel... Flower-like NaY(MoO4)2 particles were synthesized through a microwave-assisted hydrother- mal process followed by a subsequent calcination process. The products were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron mi- croscopy. The possible formation mechanism of the flower-like NaY(MoO4)2 precursor was proposed. The NaY(MoO4)2:Eu3+ phosphors were also prepared and their luminescence properties showed the NaY(MoO4)2:Eu^3+ materials with the emission peak at 612 nm had potential application as a red phosphor for white light-emitting diodes. Furthermore, the microwave-assisted hydrothermal process followed by a subsequent calcination process could be extended to prepare the other lanthanide molybdates with the flower-like morphology. 展开更多
关键词 NaY(MoO4)2 flower-like Hydrothermal method NANOMATERIAL Mechanism PHOTOLUMINESCENCE
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Targeting Effect Study of  ̄(3) H-Mitoxantrone Nanosphereson Hepatocellular Carcinoma(HCC) Model in Nude Mice
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作者 张志荣 廖工铁 侯世祥 《Journal of Chinese Pharmaceutical Sciences》 CAS 1995年第4期181-186,共6页
The distribution of  ̄(3)H-mitoxantrone polybutyl cyanoacrylate nanospheres( ̄(3)H-DHAQ-PBCA-NS)in the viscera,muscle and tumors of human hepatocellular carcinoma (HCC)model in nude mice was studied with liquid scinti... The distribution of  ̄(3)H-mitoxantrone polybutyl cyanoacrylate nanospheres( ̄(3)H-DHAQ-PBCA-NS)in the viscera,muscle and tumors of human hepatocellular carcinoma (HCC)model in nude mice was studied with liquid scintillation counting techniique. The results showed that the  ̄(3)H-DHAQ-PBCA-NS had remarkable liver targeting effect. The content of  ̄(3)H-DHAQ-PBCA-NSin liver and heterotopic liver tumor was found to be 71.31±10. 49% of total amount of drug in animal body. It was also found that the content of  ̄(3)H-DHAQ-PBCA-NS in liver was higher than that in liver tissue, and the content of  ̄(3)H-DHAQ-PBCA-NS in annpit tumor was higher than that in armpit muscle tissue,but had no significant difference;It provides an ideal preparation for the DHAQ admini-stration. 展开更多
关键词 Mitoxantrone nanospheres Liver cancer Human hepatocellular carcinoma model in nude mice Targeted drug delivery system
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SnS_2@C Hollow Nanospheres with Robust Structural Stability as High?Performance Anodes for Sodium Ion Batteries 被引量:9
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作者 Shuaihui Li Zhipeng Zhao +2 位作者 Chuanqi Li Zhongyi Liu Dan Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第1期241-249,共9页
Constructing unique and highly stable structures with plenty of electroactive sites in sodium storage materials is a key factor for achieving improved electrochemical properties through favorable sodium ion di usion k... Constructing unique and highly stable structures with plenty of electroactive sites in sodium storage materials is a key factor for achieving improved electrochemical properties through favorable sodium ion di usion kinetics. An SnS_2@carbon hollow nanospheres(SnS_2@C) has been designed and fabricated via a facile solvothermal route, followed by an annealing treatment. The SnS_2@C hybrid possesses an ideal hollow structure, rich active sites, a large electrode/electrolyte interface, a shortened ion transport pathway, and, importantly, a bu er space for volume change, generated from the repeated insertion/extraction of sodium ions. These merits lead to the significant reinforcement of structural integrity during electrochemical reactions and the improvement in sodium storage properties, with a high specific reversible capacity of 626.8 mAh g^(-1) after 200 cycles at a current density of 0.2 A g^(-1) and superior high-rate performance(304.4 mAh g^(-1) at 5 A g^(-1)). 展开更多
关键词 SnS2@C HOLLOW nanospheres ANODE materials SODIUM ion BATTERIES
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Continued sustained release of VEGF by PLGA nanospheres modified BAMG stent for the anterior urethral reconstruction of rabbit 被引量:7
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作者 Ji-Hong Wang Yue-Min Xu +4 位作者 Qiang Fu Lu-Jie Song Chao Li Qin Zhang Ming-Kai Xie 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第6期481-484,共4页
Objective:To study the biocompatibility and neovascularization of the PLGA nanospheres wrapped with vascular endothelial growth factor(VEGF).which can improve bladder acellular matrix graft(BAMG) with local continuous... Objective:To study the biocompatibility and neovascularization of the PLGA nanospheres wrapped with vascular endothelial growth factor(VEGF).which can improve bladder acellular matrix graft(BAMG) with local continuous release of VEGF.Methods:A total of 18 rabbit model (length of stenosis:3cm) with anterior urethral stricture were used as experimental animals and divided into three groups.Group A as the control group:Simple BAMG scaffold materials for urethral reconstruction.Group B as the blank group:PLGA microspheres modified BAMG for urethral reconstruction.Group C:PLGA conjugated with VEGF and modified BAMG for the urethral reconstruction.All rabbits underwent urethral angiography after 7 days,15 days,1 month and 3 months after the operation,and one rabbit in each group was sacrificed to be prepared for the organization histologic examination,HE staining,masson staining,CD31,34 and a-SAM immunohistochemical detection in the repaired sites.Results:In group A,significant urethral restenosis occurred in two rabbits after 15 days of the operation,HE and masson staining showed a lot of collagen arranged in the repaired sites,and there were a large number of inflammatory cell infiltration,and there were also CD31,34 in the repaired sites.a-SAM microvascular tag count showed a small amount of microvascular;Croup B showed anastomotic restenosis,HE and masoon staining showed inflammatory cell infiltration and collagen deposition;Group C:urethrography showed lumen patency.There were a small amount of inflammatory cell infiltration after 7 and 15 days after the operation,and there were also CD31,34 in the repaired sites.The a-SAM microvascular tag count showed many microvascular.And the difference was significant.Conclusions:Anterior urethral reconstruction with sustained-release of VEGF by PLGA nanospheres modified BAMG stents can reduce postoperative restenosis.It can also reduce collagen deposition and scar formation,promote angiogenesis of the repair tissue;therefore it in valuable in the tissue-engineered urethral reconstruction. 展开更多
关键词 Vascular ENDOTHELIAL growth factor PLGA nanospheres BLADDER ACELLULAR matrix graft
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Facile synthesis of nanoporous CuS nanospheres for high-performance supercapacitor electrodes 被引量:4
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作者 Hamid Heydari Seyyed Ebrahim Moosavifard +1 位作者 Mohammad Shahraki Saeed Elyasi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第4期762-767,共6页
In recent years, development of high-performance supercapacitor electrode materials has stimulated a great deal of scientific research. The electrochemical performance of a supercapacitor strongly depends on its mater... In recent years, development of high-performance supercapacitor electrode materials has stimulated a great deal of scientific research. The electrochemical performance of a supercapacitor strongly depends on its material structures. Herein, we report a simple strategy for high-performance supercapacitors by building pseudocapacitive CuS nanospheres with nanoporous structures, nanosized walls(<10 nm) and relatively large specific surface area of 65 m;/g. This electrode demonstrates excellent electrochemical performance including a maximum specific capacitance of 814 F/g at 1 A/g, significant rate capability of 42% capacitance retention at an ultrafast rate of 50 A/g, and outstanding long-term cycling stability at various current densities. The remarkable electrochemical performance of as-prepared nanoporous CuS nanospheres electrode has been attributed to its unique structures that plays a key role in providing short ion and electron diffusion pathways, facilitated ion transport and more active sites for electrochemical reactions. This work sheds a new light on the metal sulfides design philosophy, and demonstrates that nanoporous CuS nanospheres electrode is a promising candidate for application in high-performance supercapacitors. 展开更多
关键词 SUPERCAPACITOR NANOPOROUS CUS nanospheres
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Structure and Magnetic Properties of Monodisperse Fe^(3+)-doped CeO_2 Nanospheres 被引量:4
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作者 Sumalin Phokha Supree Pinitsoontorn Santi Maensiri 《Nano-Micro Letters》 SCIE EI CAS 2013年第4期223-233,共11页
This work reports the study concerning the structure and magnetic properties of undoped CeO_2 and Fe-doped CeO_2(Ce_(1-x) Fe_xO_2, 0.01 ≤ x ≤ 0.07) nanospheres with diameters of 100~200 nm prepared by hydrothermal m... This work reports the study concerning the structure and magnetic properties of undoped CeO_2 and Fe-doped CeO_2(Ce_(1-x) Fe_xO_2, 0.01 ≤ x ≤ 0.07) nanospheres with diameters of 100~200 nm prepared by hydrothermal method using polyvinylpyrrolidone(PVP) as surfactant. The prepared samples were studied by using X-ray diffraction(XRD), Raman spectroscopy, transmission electron microscopy(TEM), high-resolution transmission electron microscopy(HRTEM), X-ray absorption near-edge structure(XANES), and vibrating sample magnetometry(VSM). The XRD results showed that Fe-doped CeO_2 was single-phased with a cubic structure, and with Fe^(3+)successfully substituting in Ce^(4+) sites. Raman spectra showed a redshift of F_(2g) mode that caused by the Fe doping. The samples of both undoped CeO_2 and Fe-doped CeO_2 exhibited room temperature ferromagnetism, and the saturated magnetization(Ms) increased with increasing Fe content until x = 0.05, and then the samples displayed ferromagnetic loops as well as paramagnetic behavior. The roles of Ce^(3+) and Fe^(3+)spin electrons are discussed for the ferromagnetism in the Fe-doped CeO_2. 展开更多
关键词 Cerium oxide nanospheres Dilute magnetic oxide FERROMAGNETISM Oxygen vacancies XANES
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Highly sensitive room-temperature gas sensors based on hydrothermal synthesis of Cr_2O_3 hollow nanospheres 被引量:3
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作者 李盛 李凤丽 +3 位作者 周少敏 王鹏 程轲 杜祖亮 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第9期3985-3989,共5页
This paper reports that Cr2O3 hollow nanospheres (HNs) were synthesized via a hydrothermal approach and characterized by scanning electron microscopy, x-ray powder diffraction, transmission electron microscopy (TEM... This paper reports that Cr2O3 hollow nanospheres (HNs) were synthesized via a hydrothermal approach and characterized by scanning electron microscopy, x-ray powder diffraction, transmission electron microscopy (TEM), selective area electron diffraction and high resolution TEM, respectively. In addition, the room-temperature (RT) gas sensing properties of Cr2O3 HNs and conventional powders (CPs) were investigated by means of the surface photovoltage technique. The experimental data demonstrate that the RT gas sensor of the as-fabricated HNs reaches below 5 ppm whereas that of the CPs is about 40 ppm, which results from there being much more adsorbed and desorbed oxygen in HNs than in CPs at RT. The as-prepared Cr2O3 HNs could have potential applications as RT nanosensors. 展开更多
关键词 CR2O3 hollow nanospheres gas sensing surface photovoltage
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Atomic Layer Deposition-Assisted Construction of Binder-Free Ni@N-Doped Carbon Nanospheres Films as Advanced Host for Sulfur Cathode 被引量:3
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作者 Jun Liu Aixiang Wei +4 位作者 Guoxiang Pan Qinqin Xiong Fang Chen Shenghui Shen Xinhui Xia 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第4期147-160,共14页
Rational design of hybrid carbon host with high electrical conductivity and strong adsorption toward soluble lithium polysulfides is the main challenge for achieving high-performance lithium-sulfur batteries(LSBs).Her... Rational design of hybrid carbon host with high electrical conductivity and strong adsorption toward soluble lithium polysulfides is the main challenge for achieving high-performance lithium-sulfur batteries(LSBs).Herein,novel binder-free Ni@N-doped carbon nanospheres(N-CNSs)films as sulfur host are firstly synthesized via a facile combined hydrothermal-atomic layer deposition method.The cross-linked multilayer N-CNSs films can effectively enhance the electrical conductivity of electrode and provide physical blocking“dams”toward the soluble long-chain polysulfides.Moreover,the doped N heteroatoms and superficial NiO layer on Ni layer can work synergistically to suppress the shuttle of lithium polysulfides by effective chemical interaction/adsorption.In virtue of the unique composite architecture and reinforced dual physical and chemical adsorption to the soluble polysulfides,the obtained Ni@N-CNSs/S electrode is demonstrated with enhanced rate performance(816 mAh g?1 at 2 C)and excellent long cycling life(87%after 200 cycles at 0.1 C),much better than N-CNSs/S electrode and other carbon/S counterparts.Our proposed design strategy offers a promising prospect for construction of advanced sulfur cathodes for applications in LSBs and other energy storage systems. 展开更多
关键词 Atomic layer deposition Nickel N-DOPED carbon nanospheres SULFUR CATHODE Lithium-sulfur batteries
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Preparation of phosphorus-doped carbon nanospheres and their electrocatalytic performance for O_2 reduction 被引量:4
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作者 Ziwu Liu Feng Peng +3 位作者 Hongjuan Wang Hao Yu Wenxu Zheng Xianyong Wei 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第3期257-264,共8页
Phosphorus-doped carbon nanospheres without any metal residues were synthesized and characterized. The results revealed that the doping phosphorus atoms could significantly improve the electrocatalytic activity of gra... Phosphorus-doped carbon nanospheres without any metal residues were synthesized and characterized. The results revealed that the doping phosphorus atoms could significantly improve the electrocatalytic activity of graphitic carbon for the oxygen-reduction reaction (ORR) both in acidic and alkaline media, and the materials exhibited high electrocatalytic activity, long-term stability, and excellent tolerance to crossover effects especially in alkaline media. Quantum mechanics calculations with the density functional theory demonstrated that the changes in charge density and energetic characteristics of frontier orbitals for the P-doped graphene sheet could facilitate the ORR. 展开更多
关键词 varbon nanosphere oxygen reduction ELECTROCATALYSIS carbon catalysis phosphorus doping
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Effective Organochlorine Pesticides Removal from Aqueous Systems by Magnetic Nanospheres Coated with Polystyrene 被引量:2
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作者 蓝靖 CHENG Yang 赵宗山 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第1期168-173,共6页
In this paper, magnetic nanospheres coated with polystyrene (Fe3O4@PS) were prepared for the removal of organochlorine pesticides from aqueous solutions. The obtained Fe3O4@PS was round shape with diameter of 55... In this paper, magnetic nanospheres coated with polystyrene (Fe3O4@PS) were prepared for the removal of organochlorine pesticides from aqueous solutions. The obtained Fe3O4@PS was round shape with diameter of 55±11 nm. The VSM results illustrated that its higher saturated magnetization was 36.76 emu g^-1 and it could be easily separated from aqueous solutions with a permanent magnet. The adsorption results showed that pesticides could be effectively adsorbed and the adsorption equilibrium time was less than 20 mins. The pseudo-second-order model was suitable to describe the adsorption kinetics. Compared with the Freundlich adsorption model, the adsorption data fitted well with Langmuir model. The effect of salinity and humic acid was also studied and the results illustrated that they could be neglected under optimized conditions. The asobtained sorbent showed a good performance with more than 93.3% pesticides removal in treating actual water samples. 展开更多
关键词 magnetic nanospheres POLYSTYRENE ADSORPTION organochlorine.
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Fabrication of Fluorescent Porphyrin/Polystyrene Composite Nanospheres by Electrospinning 被引量:2
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作者 SONG Yan ZHAN Nai-qian +3 位作者 YU Miao YANG Qing-biao ZHANG Chao-qun LI Yao-xian 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第1期148-151,共4页
Fluorescent polystyrene(PS)/porphyrin(TPPA) composite nanospheres were successfully fabricated by electrospinning. The SEM images clearly show that owing to adding TPPA in PS, the averaged diameter of the composit... Fluorescent polystyrene(PS)/porphyrin(TPPA) composite nanospheres were successfully fabricated by electrospinning. The SEM images clearly show that owing to adding TPPA in PS, the averaged diameter of the composite nanospheres became smaller, from 1500 to 580 nm. Fourier-transform infrared(FTIR) spectra determined the chemical composition of the resulting PS/TPPA composite nanospheres. The photoluminescent(PL) spectral analysis indicates that the peak position of the composite nanospheres in either solid state or water is identical to that of pure TPPA, at about 652 nm, and is still unchangeable when they are left for at least 20 d, indicating the stable photoluminescent property of the fluorescent composite nanospheres. 展开更多
关键词 POLYSTYRENE PORPHYRIN FLUORESCENT Composite nanosphere ELECTROSPINNING
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Photocatalytic Activity of Hierarchical Flower-Like TiO_(2) Superstructures with Dominant {001} Facets 被引量:27
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作者 XIANG Quanjun YU Jiaguo 《催化学报》 SCIE EI CAS CSCD 北大核心 2011年第4期525-531,共7页
The fabrication of well defined hierarchical structures of anatase TiO_(2) with a high percentage of reactive facets is of great importance and challenging.Hierarchically flower-like TiO_(2) superstructures(HFTS)self-... The fabrication of well defined hierarchical structures of anatase TiO_(2) with a high percentage of reactive facets is of great importance and challenging.Hierarchically flower-like TiO_(2) superstructures(HFTS)self-assembled from anatase TiO_(2) nanosheets with exposed{001}facets(up to 87%)were synthesized by a simple alcohothermal strategy in a HF-H_(2)O-C_(2)H_(5)OH mixed solution using titanate nanotubes as precursor.The samples were characterized by X-ray diffraction,scanning electron microscopy,transmission electron microscopy,and N2 adsorption-desorption isotherms.The photocatalytic activity was evaluated by the photocatalytic oxidation decomposition of acetone in air and methyl orange in aqueous solution under UV illumination.The photocatalytic activity of HFTS was much higher than that of commercial Degussa P25 and tabular-shaped anatase TiO_(2) obtained using pure water as the synthesis medium.The enhancement in photocatalytic activity was related to several factors,including the hierarchically porous structure,exposed{001}facets,and increased light harvesting ability.The HFTS was also of interest for use in solar cells,photocatalytic H_(2) production,optoelectronic devices,sensors,and catalysis. 展开更多
关键词 titanium dioxide {001}facet hierarchical flower-like titanium dioxide superstructure photocatalytic activity acetone methyl orange
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Superior de/hydrogenation performances of MgH2 catalyzed by 3D flower-like TiO2@C nanostructures 被引量:9
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作者 Meng Zhang Xuezhang Xiao +3 位作者 Bosang Luo Meijia Liu Man Chen Lixin Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第7期191-198,I0006,共9页
Magnesium hydride has been seen as a potential material for solid state hydrogen storage,but the kinetics and thermodynamics obstacles have hindered its development and application.Three-dimensional flower-like TiO2@C... Magnesium hydride has been seen as a potential material for solid state hydrogen storage,but the kinetics and thermodynamics obstacles have hindered its development and application.Three-dimensional flower-like TiO2@C and TiO2 were synthesized as the catalyst for MgH2 system and great catalytic activities are acquired in the hydrogen sorption properties.Experiments also show that the flower-like TiO2@C is superior to flower-like TiO2 in improving the hydrogen storage properties of MgH2.The hydrogen desorption onset and peak temperatures of flower-like TiO2 doped MgH2 is reduced to 199.2℃and 245.4℃,while the primitive MgH2 starts to release hydrogen at 294.6℃and the rapid dehydrogenation temperature is even as high as 362.6℃.The onset and peak temperatures of flower-like TiO2@C doped MgH2 are further reduced to 180.3℃and 233.0℃.The flower-like TiO2@C doped MgH2 composite can release6.0 wt%hydrogen at 250℃within 7 min,and 4.86 wt%hydrogen at 225℃within 60 min,while flowerlike TiO2 doped MgH2 can release 6.0 wt%hydrogen at 250℃within 8 min,and 3.89 wt%hydrogen at225℃within 60 min.Hydrogen absorption kinetics is also improved dramatically.Moreover,compared with primitive MgH2 and the flower-like TiO2 doped MgH2,the activation energy of flower-like TiO2@C doped MgH2 is significantly decreased to 67.10 kJ/mol.All the improvement of hydrogen sorption properties can be ascribed to the flower-like structure and the two-phase coexistence of TiO2 and amorphous carbon.Such phase composition and unique structure are proved to be the critical factor to improve the hydrogen sorption properties of MgH2,which can be considered as the new prospect for improving the kinetics of light-metal hydrogen storage materials. 展开更多
关键词 Hydrogen storage Magnesium hydride TIO2 flower-like structure Catalytic effects
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