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Synchronous organic-inorganic co-intercalated ammonium vanadate cathode for advanced aqueous zinc-ion batteries
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作者 Wenpei Kang Bingchen Zhang +8 位作者 Zhurui Wang Zhengchunyu Zhang Mang Niu Xuguang An Zhenkai Mou Xiaoyu Fan Xuqiang Hu Baojuan Xi Shenglin Xiong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期608-617,共10页
Vanadium-based cathode materials are attractive for aqueous zinc-ion batteries(AZIBs)owing to the high capacity from their open frameworks and multiple valences.However,the cycle stability and rate capability are stil... Vanadium-based cathode materials are attractive for aqueous zinc-ion batteries(AZIBs)owing to the high capacity from their open frameworks and multiple valences.However,the cycle stability and rate capability are still restricted by the low electrical conductivity and trapped diffusion kinetics.Here,we propose an organic-inorganic co-intercalation strategy to regulate the structure of ammonium vanadate(NH_(4)V_(4)O_(10),NVO).The introduction of Al^(3+)and polyaniline(PANI)induces the optimized layered structure and generation of urchin-like hierarchical construction(AP-NVO),based on heterogeneous nucleation and dissolution-recrystallization growth mechanism.Owing to these favorable features,the AP-NVO electrode delivers a desirable discharge capacity of 386 mA h g^(-1) at 1.0 A g^(-1),high-rate capability of 263 mA h g^(-1 )at 5.0 A g^(-1) and excellent cycling stability with 80.4%capacity retention over 2000 cycles at 5.0 A g^(-1).Such satisfactory electrochemical performance is believed to result from the enhanced reaction kinetics provided by the stable layered structure and a high intercalation pseudo-capacitance reaction.These results could provide enlightening insights into the design of layered vanadium oxide cathodematerials. 展开更多
关键词 Ammonium vanadate bronze Co-pre-intercalation Urchin-like hierarchical structure Aqueous zinc-ion batteries
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Tailoring NH_(4)^(+)storage by regulating oxygen defect in ammonium vanadate
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作者 Yanyan Liu Ziyi Feng +3 位作者 Hanmei Jiang Xueying Dong Changgong Meng Yifu Zhang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第7期1171-1182,共12页
Defect engineering is an effective strategy for modifying the energy storage materials to improve their electrochemical performance.However,the impact of oxygen defect and its content on the electrochemical performanc... Defect engineering is an effective strategy for modifying the energy storage materials to improve their electrochemical performance.However,the impact of oxygen defect and its content on the electrochemical performances in the burgeoning aqueous NH_(4)^(+)storage field remains explored.Therefore,for the first time in this work,an oxygen-defective ammonium vanadate[(NH_(4))_(2)V_(10)O_(25)·8H_(2)O,denoted as Od-NHVO]with a novel 3D porous flower-like architecture was achieved via the reduction of thiourea in a mild reaction condition,which is a facile method that can realize the intention to regulate the oxygen defect content,with the capability of mass-production.The as-prepared Od_M-NHVO with moderate oxygen defect content can deliver a stable specific capacitance output(505 F g^(-1),252 mAh g^(-1)at 0.5 A g^(-1)with~80% capacitance retention after 10,000 cycles),which benefits from extra active sites,unimpeded NH_(4)^(+)-migration path and relatively high structure integrity.In contrast,low oxygen defect content will lead to the torpid electrochemical reaction kinetics while too high content of it will reduce the chargestorage capability and induce structural disintegration.The superior NH_(4)^(+)-storage behavior is achieved with the reversible intercalation/deintercalation process of NH_(4)^(+)accompanied by forming/breaking of hydrogen bond.As expected,the assembled flexible OdM-NHVO//PTCDI quasi-solid-state hybrid supercapacitor(FQSS HSC)also exhibits high areal capacitance,energy density and reliable flexibility.This work provides a new avenue for developing materials with oxygen-deficient structure for application in various aqueous non-metal cation storage systems. 展开更多
关键词 Ammonium vanadate Oxygen defect Ammonium-ion storage Hybrid supercapacitors Electrochemical performance
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980-nm all-fiber mode-locked Yb-doped phosphate fiber oscillator based on semiconductor saturable absorber mirror and its amplifier 被引量:4
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作者 李平雪 姚毅飞 +6 位作者 池俊杰 胡浩伟 张光举 梁博兴 张孟孟 马春媚 苏宁 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第8期185-190,共6页
A 980-nm semiconductor saturable absorber mirror(SESAM) mode-locked Yb-doped phosphate fiber laser is demonstrated by using an all-fiber linear cavity configuration. Two different kinds of cavity lengths are introdu... A 980-nm semiconductor saturable absorber mirror(SESAM) mode-locked Yb-doped phosphate fiber laser is demonstrated by using an all-fiber linear cavity configuration. Two different kinds of cavity lengths are introduced into the oscillator to obtain a robust and stable mode-locked seed source. When the cavity length is chosen to be 6 m, the oscillator generates an average output power of 3.5 m W and a pulse width of 76.27 ps with a repetition rate of 17.08 MHz. As the cavity length is optimized to short, 4.4-m W maximum output power and 61.15-ps pulse width are produced at a repetition rate of 20.96 MHz. The output spectrum is centered at 980 nm with a narrow spectral bandwidth of 0.13 nm. In the experiment, no undesired amplified spontaneous emission(ASE) nor harmful oscillation around 1030 nm is observed. Moreover,through a two-stage all-fiber-integrated amplifier, an output power of 740 m W is generated with a pulse width of 200 ps. 展开更多
关键词 980-nm fiber laser SESAM mode-locking yb-doped phosphate fiber fiber amplifier
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A theoretical and experimental study on all-normal-dispersion Yb-doped mode-locked fiber lasers 被引量:2
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作者 池俊杰 李平雪 +6 位作者 杨春 赵自强 李尧 王雄飞 钟国舜 赵鸿 姜东升 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期268-273,共6页
We report on a theoretical and experimental study of an all-normal-dispersion (ANDi) Yb-doped mode-locked fiber laser, in which nonlinear polarization rotation (NPR) is used to realize mode-locking without any dis... We report on a theoretical and experimental study of an all-normal-dispersion (ANDi) Yb-doped mode-locked fiber laser, in which nonlinear polarization rotation (NPR) is used to realize mode-locking without any dispersion compensation. Based on the coupled nonlinear Schr6dinger (CNLS) equation, a model simulating the mode-locked process of an all-normal-dispersion ring fiber laser is developed, which shows that the achievement of stable mode-locking depends on the alignment of the polarization controller (PC) along the fast-polarization axis of the fiber, the birefringence intensity, and the net cavity dispersion. According to the theoretical analysis, stable mode-locked pulses with pulse duration 300 ps and average output power 33.9 mW at repetition rate 36 MHz are obtained. 展开更多
关键词 all-normal-dispersion nonlinear polarization rotation MODE-LOCKED yb-doped fiber laser
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Stimulated Brillouin Scattering Enhancement Factor Improvement in a 11.6-GHz-Linewidth 1.5-kW Yb-Doped Fiber Amplifier 被引量:2
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作者 刘广柏 杨依枫 +7 位作者 王建华 郑也 陈晓龙 刘恺 赵纯 漆云凤 何兵 周军 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第7期94-97,共4页
The stimulated Brillouin scattering (SBS) threshold enhancement factor in a pure white noise linewidth broad- ening Yb-doped fiber amplifier (YDFA) with a short large mode area fiber is theoretically and experimen... The stimulated Brillouin scattering (SBS) threshold enhancement factor in a pure white noise linewidth broad- ening Yb-doped fiber amplifier (YDFA) with a short large mode area fiber is theoretically and experimentally studied. We demonstrate a 1064.08nm, 11.6 GHz finewidth, 1.5 k W output power YDFA with an SBS threshold enhancement of -57 (26 W SBS threshold with single frequency seed). The output beam is near-diffraction lim- ited with a beam quality factor elM2 = 1.15 and a slope efficiency of up to 87%. No SBS or stimulated Raman scattering effects are observed in the whole power range. Further power sealing is limited by the available pump power in our system. 展开更多
关键词 SBS of Stimulated Brillouin Scattering Enhancement Factor Improvement in a 11.6-GHz-Linewidth 1.5-kW yb-doped Fiber Amplifier Yb is in GHz
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High-energy pulse generation using Yb-doped Q-switched fiber laser based on single-walled carbon nanotubes 被引量:1
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作者 王军利 汪雪玲 +3 位作者 贺博荣 朱江峰 魏志义 王勇刚 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期532-535,共4页
An all-fiber laser using a single-walled carbon nanotube(SWCNT) as the saturable absorber(SA) for Q-switched operation in the 1031 nm region is demonstrated in this work. A lasing threshold as low as 17 mW was rea... An all-fiber laser using a single-walled carbon nanotube(SWCNT) as the saturable absorber(SA) for Q-switched operation in the 1031 nm region is demonstrated in this work. A lasing threshold as low as 17 mW was realized for continuous wave operation. By further increasing the pump power, stable Q-switched pulse trains are obtained when the pump power ranges from 38 mW to 125 mW, corresponding to repetition rate varying from 40.84 kHz to 66.24 kHz, the pulse width from 2.0 μs to 1.0 μs,and the highest single pulse energy of 40.6 nJ respectively. 展开更多
关键词 yb-doped Q-switching all-fiber lasers single-walled carbon nanotubes
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Tunable and Switchable Narrow Bandwidth Semiconductor-Saturable Absorber Mirror Mode-Locked Yb-Doped Fiber Laser Delivering Different Pulse Widths 被引量:1
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作者 王兆坤 邹峰 +2 位作者 王子薇 杜松涛 周军 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第3期36-39,共4页
The wavelength-tunable and switchable narrow bandwidth mode-locking operation is demonstrated in an all fiber laser based on semiconductor-saturable absorber mirror (SESAM). Two narrow-band fiber Bragg gratings cent... The wavelength-tunable and switchable narrow bandwidth mode-locking operation is demonstrated in an all fiber laser based on semiconductor-saturable absorber mirror (SESAM). Two narrow-band fiber Bragg gratings centered at 1029.9nm and 1032nm respectively with a polarization controller inserted between them are used to realize the wavelength switchable between 1029.9nm and 1032nm. The laser delivers different pulse widths of 7.5ps for 1030nm and 20ps for 1032nm. The maximum output power for both could reach -6.5mW at single pulse operation. The output wavelength couM be tuned to about 0.gnm intervals ranging from 1030.2nm to 1031.1 nm and from 1032.15nm to 1033.7nm with the temperature change of the fiber Bragg grating, respectively. 展开更多
关键词 mode in Yb of Tunable and Switchable Narrow Bandwidth Semiconductor-Saturable Absorber Mirror Mode-Locked yb-doped Fiber Laser Delivering Different Pulse Widths nm
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Generation of Broadband Spectrum from a Simple Nonlinear-Polarization-Evolution Mode-Locked Yb-Doped Fiber Oscillator 被引量:1
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作者 谢阳 韩海年 +1 位作者 刘文军 魏志义 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第5期91-93,共3页
We demonstrate a nonlinear polarization evolution mode-locked Yb-doped fiber oscillator with the broadband spectrum output operating in a dispersion-managed regime. Pumped by a 976 nm single-mode laser diode, stable m... We demonstrate a nonlinear polarization evolution mode-locked Yb-doped fiber oscillator with the broadband spectrum output operating in a dispersion-managed regime. Pumped by a 976 nm single-mode laser diode, stable mode-locked ultrashort pulses are emitted with an average power of 198mW at a repetition rate of 124MHz, corresponding to a pulse energy of 1.6nJ. The output spectrum spans from 950nm to ll50nm so that the transform-limited pulse duration is as short as 23 fs. Due to the imperfect dispersion compensation, we compress the pulses to 32 fs in this experiment. 展开更多
关键词 Yb Generation of Broadband Spectrum from a Simple Nonlinear-Polarization-Evolution Mode-Locked yb-doped Fiber Oscillator
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Synthesis and Crystal Structure of Yb-doped S-FAP
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作者 袁欣 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第2期205-208,共4页
To abtain large crystals for improving the physical and optical properties of materials, the crystal of Yb-doped S-FAP was sythesized by the Czochralski method, the growth process was analyzed, and its structure was d... To abtain large crystals for improving the physical and optical properties of materials, the crystal of Yb-doped S-FAP was sythesized by the Czochralski method, the growth process was analyzed, and its structure was determined. This material was confirmed to have a hexagonal structure, unit-cell parameters (a=b-0.9683(4) nm, c=0.7277(4) nm) are slightly different from the crystal parameters of S-FAP reported before. 展开更多
关键词 yb-doped S-FAP crystal structure ABSORPTION
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A 980 nm Yb-doped single-mode fibre laser with 946 nm Nd:YAG laser as pump source
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作者 李平雪 邹淑珍 +1 位作者 张雪霞 李港 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期302-307,共6页
Based on rate equations, this paper gives expressions of the output power, the pump power threshold, the slope efficiency, the fibre optimal length and the laser gain of a quasi-three-level Yb-doped fibre laser. The g... Based on rate equations, this paper gives expressions of the output power, the pump power threshold, the slope efficiency, the fibre optimal length and the laser gain of a quasi-three-level Yb-doped fibre laser. The gain relationship between quasi-three-level system and four-level system is also given, which provides a theoretical basis for suppressing the four-level transmissions. In the experiment, we adopt the backward pumping configuration and use a linear cavity. The Yb-doped fibre laser has an output power of 372 mW of single-mode laser emission at 980 nm with a slope efficiency of 21.2% when the fibre length is 29.5 cm close to an optimal fibre length in theory. The experimental results accord well with the theoretical analyses. 展开更多
关键词 QUASI-THREE-LEVEL yb-doped fibre 980 nm laser
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An Efficient Single-Frequency Yb-Doped All-Fiber MOPA Laser at 1064.3 nm
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作者 康进 陆宝乐 +6 位作者 齐新元 冯晓强 陈浩伟 江曼 王洋 付盼 白晋涛 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第12期54-57,共4页
An efficient narrow=linewidth single-frequency (SF) Yb-doped all-fiber master oscillator power amplifier (MOPA) laser operating at 1064.3 nm is demonstrated experimentally. A ring cavity SF fiber laser is used as ... An efficient narrow=linewidth single-frequency (SF) Yb-doped all-fiber master oscillator power amplifier (MOPA) laser operating at 1064.3 nm is demonstrated experimentally. A ring cavity SF fiber laser is used as the seed source for the MOPA system and the Yb-doped fibers are employed as the gain medium or the saturable absorber. The SF operation is observed to be stable without mode hopping. The highest output power of 266 mW is obtained under the 400row pump power with the corresponding slope efficiency of 66.2-. The Hnewidth of the amplified output laser is approximately I kHz and its optical signal-to-noise ratio is over 45 dB. 展开更多
关键词 MOPA as be SF is Yb An Efficient Single-Frequency yb-doped All-Fiber MOPA Laser at 1064.3 nm
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Wideband All-Polarization-Maintaining Yb-Doped Mode-Locked Fiber Laser Using a Nonlinear Optical Loop Mirror
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作者 林一楠 方文坛 +1 位作者 顾春 许立新 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期43-45,共3页
We report on a wide-band and stable mode-locked all-polarization-maintaining fiber laser configuration using a nonlinear optical loop mirror. The central wavelength of the laser is 1080.14nm and the 3dB bandwidth is 2... We report on a wide-band and stable mode-locked all-polarization-maintaining fiber laser configuration using a nonlinear optical loop mirror. The central wavelength of the laser is 1080.14nm and the 3dB bandwidth is 20.29nm. The repetition rate of the pulse is 3.28 MHz and the pulse width is 848ps. By tuning the pump power, which is centered at 980nrn, from 300mW to 380mW, we obtain a linearly changed output power from 6row to 7.12roW. The all-polarization-mMntaining fiber configuration is fundamental to the stability of the output power. 展开更多
关键词 YB in on mode of Wideband All-Polarization-Maintaining yb-doped Mode-Locked Fiber Laser Using a Nonlinear Optical Loop Mirror
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Experimental Investigation of Wavelength-Tunable All-Normal-Dispersion Yb-Doped Mode-Locked Fiber Lasers:Compression and Amplification
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作者 肖晓晟 华弋 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期63-65,共3页
Wavelength-tunable ultrashort pulse source with high energy is highly desired for a lot of applications. The wavelength-tunable all-normal-dispersion (ANDi) mode-locked fiber laser, which can be compressed easily an... Wavelength-tunable ultrashort pulse source with high energy is highly desired for a lot of applications. The wavelength-tunable all-normal-dispersion (ANDi) mode-locked fiber laser, which can be compressed easily and amplified by an all-fiber structure, is a promising seed of such a source with compact structures. The pulse compression and amplification at different center wavelengths (from 1026 to 1058nm) of the tunable ANDi Yb- doped mode-locked fiber lasers that we previously proposed are experimentally investigated in this work. It is found that, for different wavelengths, the duration and chirp of the direct output pulse from the oscillator vary considerably, however, the duration of compressed pulse fluctuates less. For the amplification process, due to the unf/at gain spectrum of Yb-doped fiber, the gain at a short wavelength is larger than that at a long wavelength. Consequently, the trends of spectrum distortions induced by the amplification process are different for different wavelengths. These results and analyses will be helpful for the design of a high-energy and wavelength-tunable ultrashort pulse source based on an ANDi seed. 展开更多
关键词 LENGTH In Yb Experimental Investigation of Wavelength-Tunable All-Normal-Dispersion yb-doped Mode-Locked Fiber Lasers:Compression and Amplification
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Passively Q-Switched Yb-Doped Fiber Laser Operating at 1.06 μm with Two-Dimensional Silver Nanoplate as Saturable Absorber
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作者 ShengoGui Fu Xue-Ying Ouyang +1 位作者 Jin-Jian Li Xiao-Juan Liu 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第4期46-49,共4页
A two-dimensional silver nanoplate is prepared with the seed-mediated growth method and is used for achieving pulse fiber laser operation. By controlling the dimension parameters of the silver nanoplate, the surface p... A two-dimensional silver nanoplate is prepared with the seed-mediated growth method and is used for achieving pulse fiber laser operation. By controlling the dimension parameters of the silver nanoplate, the surface plasmon resonance absorption peak of the material is successfully adjusted to 1068 nm. Based on the silver nanoplate as a saturable absorber, a passively Q-switched Yb-doped fiber laser operating at 1062 nm is demonstrated. The maximum average output power of 3.49mW is obtained with a minimum pulse width of 1.84#s at a pulse repetition rate of 65.TkHz, and the corresponding pulse energy and peak power are 53.1 nJ and 28.8mW, respectively. 展开更多
关键词 YB m with Two-Dimensional Silver Nanoplate as Saturable Absorber Passively Q-Switched yb-doped Fiber Laser Operating at 1.06
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Fast and Stable Zinc Anode‑Based Electrochromic Displays Enabled by Bimetallically Doped Vanadate and Aqueous Zn^(2+)/Na^(+)Hybrid Electrolytes
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作者 Zhaoyang Song Bin Wang +5 位作者 Wu Zhang Qianqian Zhu Abdulhakem YElezzabi Linhua Liu William WYu Haizeng Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第12期231-241,共11页
Vanadates are a class of the most promising electrochromic materials for displays as their multicolor characteristics.However,the slow switching times and vanadate dissolution issues of recently reported vanadates sig... Vanadates are a class of the most promising electrochromic materials for displays as their multicolor characteristics.However,the slow switching times and vanadate dissolution issues of recently reported vanadates significantly hinder their diverse practical applications.Herein,novel strategies are developed to design electrochemically stable vanadates having rapid switching times.We show that the interlayer spacing is greatly broadened by introducing sodium and lanthanum ions into V_(3)O_(8)interlayers,which facilitates the transportation of cations and enhances the electrochemical kinetics.In addition,a hybrid Zn^(2+)/Na^(+)electrolyte is designed to inhibit vanadate dissolution while significantly accelerating electrochemical kinetics.As a result,our electrochromic displays yield the most rapid switching times in comparison with any reported Zn-vanadate electrochromic displays.It is envisioned that stable vanadate-based electrochromic displays having video speed switching are appearing on the near horizon. 展开更多
关键词 vanadates Hybrid electrolytes DISPLAYS Electrochromic
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离子液体热合成法制备钒酸铁及其电化学性能
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作者 赵鹬 李忠英 +2 位作者 雷福红 张宇婷 李世友 《精细化工》 EI CAS CSCD 北大核心 2024年第6期1354-1361,共8页
以离子液体1-丁基-3-甲基咪唑酸溴盐([Bmim]Br)为反应溶剂,采用离子液体热合成法制备了钒酸铁前驱体,通过煅烧和后处理成功地合成了粒径均一、排布密集的FeVO_(4)纳米颗粒。采用SEM、XRD、XPS、TEM、N_(2)吸附-脱附对材料的结构和形貌... 以离子液体1-丁基-3-甲基咪唑酸溴盐([Bmim]Br)为反应溶剂,采用离子液体热合成法制备了钒酸铁前驱体,通过煅烧和后处理成功地合成了粒径均一、排布密集的FeVO_(4)纳米颗粒。采用SEM、XRD、XPS、TEM、N_(2)吸附-脱附对材料的结构和形貌进行了表征。以FeVO_(4)纳米颗粒为负极材料构建了锂离子电池,采用恒流充电放电测试、循环伏安法(CV)和电化学阻抗对电池进行了电化学性能评价。结果表明,Fe VO_(4)电极作为锂离子电池负极材料在高电流密度下表现出优异的循环性能和电化学性能,其在300 mA/g电流密度下的初始放电比容量为1471.58 mA·h/g,在300 mA/g下循环100次后,仍获得783.00 mA·h/g的高比容量,其优异的电化学性能可能归因于电极材料的纳米级尺寸。 展开更多
关键词 钒酸铁 离子液体热合成法 锂离子电池 负极材料 有机电化学
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钒酸铋基异质结光催化剂研究进展
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作者 肖力光 王一鸣 雷潭 《应用化工》 CAS CSCD 北大核心 2024年第2期408-413,共6页
综述了钒酸铋(BiVO_(4))基异质结光催化材料的研究进展,针对BiVO_(4)基异质结光催化材料带隙较窄、光生载流子复合率较高等缺点,阐述了BiVO_(4)基异质结光催化材料的异质结类型,详细介绍了BiVO_(4)基异质结光催化材料在水分解领域、降... 综述了钒酸铋(BiVO_(4))基异质结光催化材料的研究进展,针对BiVO_(4)基异质结光催化材料带隙较窄、光生载流子复合率较高等缺点,阐述了BiVO_(4)基异质结光催化材料的异质结类型,详细介绍了BiVO_(4)基异质结光催化材料在水分解领域、降解有机污染物、还原CO_(2)和重金属离子领域的研究进展,分析了BiVO_(4)基异质结光催化材料目前存在的问题,对今后的研究重点和方向做出了展望。 展开更多
关键词 光催化 钒酸铋 异质结 研究进展
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高性能YVO_(4)基稀土杂化发光材料的构建及其能量传递机制
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作者 唐鹿 《化工新型材料》 CAS CSCD 北大核心 2024年第5期162-166,共5页
采用溶剂热和离子交换两步实验法,以YVO_(4)为无机基质,2-噻吩甲酰三氟丙酮(TTA)为有机配体,构建了具有核壳结构的YVO_(4)∶Eu^(3+)@YVO_(4)∶Eu^(3+)-TTA稀土杂化发光材料,研究了其高效的发光性能和内部的能量传递机制。结果表明,在62... 采用溶剂热和离子交换两步实验法,以YVO_(4)为无机基质,2-噻吩甲酰三氟丙酮(TTA)为有机配体,构建了具有核壳结构的YVO_(4)∶Eu^(3+)@YVO_(4)∶Eu^(3+)-TTA稀土杂化发光材料,研究了其高效的发光性能和内部的能量传递机制。结果表明,在621nm的监控波长下,YVO_(4)∶Eu^(3+)@YVO_(4)∶Eu^(3+)-TTA稀土杂化发光材料在280~420nm范围内有两个很强的吸收峰(即V-O峰和TTA特征吸收峰)。YVO_(4)基质通过交换作用能量传递,而TTA有机配体通过分子内能量传递,可将吸收的紫外光能量有效地传递给Eu^(3+),从而实现了Eu^(3+)更高效的可见光(红光)发射。 展开更多
关键词 钒酸钇 宽谱激发 稀土杂化发光材料 发光性能 能量传递机制
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AZ31B镁合金钒/硅烷复合转化膜的制备与表征 被引量:2
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作者 董丽惠 王华 李琳 《表面技术》 EI CAS CSCD 北大核心 2024年第4期34-45,共12页
目的改善钒酸盐转化膜表面形貌,提高单一钒酸盐转化膜的耐蚀性能。方法使用偏钒酸盐和硅烷通过两步法在镁合金表面制备钒/硅烷复合转化膜,比较不同硅烷制备的复合膜的耐蚀性能,从而确定使用硅烷的种类,采用扫描电子显微镜(SEM)、X射线能... 目的改善钒酸盐转化膜表面形貌,提高单一钒酸盐转化膜的耐蚀性能。方法使用偏钒酸盐和硅烷通过两步法在镁合金表面制备钒/硅烷复合转化膜,比较不同硅烷制备的复合膜的耐蚀性能,从而确定使用硅烷的种类,采用扫描电子显微镜(SEM)、X射线能谱(EDS)、X射线光电子能谱(XPS)和傅里叶红外光谱(FT-IR)观察转化膜的微观形貌并分析转化膜的组成和结构,通过交流阻抗测试(EIS)、Tafel极化曲线测试和全浸腐蚀实验评价转化膜的耐蚀性能,并采用划格实验和接触角测试评价转化膜的结合力和疏水性。结果确定使用BTEPST(双-[3-(三乙氧基硅)丙基]-四硫化物)作为成膜组分,使用偏钒酸钠和BTESPT在镁合金表面成功制备钒/BTESPT复合膜,复合膜表面均匀平整,致密无裂纹,与基体结合力好,具有疏水性,该复合膜的组成元素为Mg、V、C、O、Si和S,且元素分布较均匀,膜层是包含Si—O—S、Si—O—Mg、Si—O—V等共价键的交联结构。交流阻抗测试结果显示,钒/BTESPT复合转化膜的膜层电阻为1.17×10^(5)Ω·cm^(2),电荷转移电阻为1.076×10^(5)Ω·cm^(2)。极化曲线测试结果表明,复合膜的腐蚀电位为-1.4570V,腐蚀电流密度为1.4980×10^(-7)A·cm^(-2),腐蚀电流密度相较于基体降低约2个数量级,对镁合金的保护效率达到99.6%。复合转化膜在3.5%(质量分数)NaCl溶液中长期浸泡10d未发生明显腐蚀,全浸实验浸泡14d腐蚀速率为0.0580 g/(m^(2)·h),未处理的镁合金腐蚀速率则为0.5186 g/(m^(2)·h)。结论钒/BTESPT复合膜能进一步提高钒酸盐转化膜对AZ31B镁合金的保护性能。 展开更多
关键词 镁合金 表面处理 化学转化膜 钒酸盐 硅烷 耐蚀性
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铁掺杂氮化碳/BiVO_(4)构建Z型光催化全解水 被引量:1
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作者 刘智焬 戚荣杰 +3 位作者 罗皓霖 叶朕 江治 上官文峰 《分子催化(中英文)》 CAS CSCD 北大核心 2024年第2期112-120,I0001,I0002,共11页
采用气相挥发法在聚合物氮化碳(PCN)结构中引入了适量的铁(Fe)掺杂组分,成功制备出具有可调Fe掺杂浓度的PCN半导体光催化剂,其中0.55%(w) Fe掺杂的PCN析氢催化活性(410μmol·h^(-1))为原始PCN的2.6倍并通过XRD、UV-Vis、PL、XPS、... 采用气相挥发法在聚合物氮化碳(PCN)结构中引入了适量的铁(Fe)掺杂组分,成功制备出具有可调Fe掺杂浓度的PCN半导体光催化剂,其中0.55%(w) Fe掺杂的PCN析氢催化活性(410μmol·h^(-1))为原始PCN的2.6倍并通过XRD、UV-Vis、PL、XPS、SEM等表征阐明了Fe掺杂对PCN的影响和作用机理.同时调控钒酸铋的生长环境(配合剂、水热时间、pH)合成了具备不同形貌的钒酸铋(BiVO4),进一步成功合成了暴露{010}和{-121}晶面的十面体BiVO_(4).Z型体系中还原和氧化过程分离,可以在不同催化剂上分别进行氧化还原反应,能够有效抑制逆反应的发生,同时扩宽光催化材料的设计和选择的可能性.以PCN作为产氢端催化剂,十面体BiVO_(4)作为产氧端催化剂,以Fe^(3+)/Fe^(2+)作为离子对构建了Z型体系实现了光催化全解水.其中0.55%Fe掺杂的PCN-Fe/BiVO_(4)表现出了更优异的光催化活性,全解水的产氢性能比未改性的PCN/BiVO_(4)提升近一倍,进一步验证了气相挥发法掺杂Fe改性策略的有效性.这种基于催化剂(氮化碳)性质的掺杂改性方法对于催化剂的优化和设计以及构建Z型光催化全解水体系的探索具备一定的借鉴意义. 展开更多
关键词 氮化碳 铁掺杂 钒酸铋 Z型体系 光催化
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