Lignin is the most abundant and important macromolecule in organic matter and its yield is second only to cellulose. Lignin is abundant in source, low in price, and has a large number of active groups such as methoxy ...Lignin is the most abundant and important macromolecule in organic matter and its yield is second only to cellulose. Lignin is abundant in source, low in price, and has a large number of active groups such as methoxy group and carboxyl group, so it has great utilization value. We used lignin as a carbon source to prepare porous carbon nanosphere(PCN) materials, and in-situ synthesized the MoS_ 2 on its surface. The high specific surface area(462.8 m^2/g), large pore volume and good electron conductivity of the porous carbon scaffold facilitated the reversible electro-chemical reaction of S towards metallic Li, and thus the nano-hybrid showed a high specific energy and excellent cycle stability which still remained 520m Ah/g after 50 cycles.展开更多
The RE-Mg-Ni-Mn-based AB2-type La(1-x)CexMgNi(3.5)Mn(0.5)( x = 0- 0. 4) alloys were prepared by spinning treatment. For obtaining the optimum performance,the effects of Ce content and spinning rate on the hydr...The RE-Mg-Ni-Mn-based AB2-type La(1-x)CexMgNi(3.5)Mn(0.5)( x = 0- 0. 4) alloys were prepared by spinning treatment. For obtaining the optimum performance,the effects of Ce content and spinning rate on the hydrogen storage performance of the alloys were studied systematically. The results show that the variations of the spinning rate and Ce content result in noteworthy changes of the phase content without altering phase composition of the alloys. Specifically,the LaMgNi4 phase increases and LaNi5 phase decreases when increasing the spinning rate and Ce content. Furthermore,the crystalline grains of Cecontaining alloys prepared by spinning treatment are remarkably refined. The alloys own superior electrochemical performance. All alloys reach the optimal discharge capacity at the initial cycle. Increasing Ce content and spinning rate lead the discharge capacity and electrochemical kinetics rise to an optimal value and then start to reduce. Meanwhile,the electrochemical cycle stability is also improved,which is ascribed to the great enhancement of anti-pulverization and anti-corrosion abilities resulting from the spinning treatment and the substitution of Ce for La.展开更多
在这项工作中,我们采用简单的水热方法在泡沫镍基底上生长了钴酸镍纳米片。结果表明,合成的NiCo2O4纳米片直接用作超级电容器电极,呈现出优异的电化学性能。在电流密度为1 m A·cm^-2时,其面积比电容达到1.26 C·cm^-2;经过1000...在这项工作中,我们采用简单的水热方法在泡沫镍基底上生长了钴酸镍纳米片。结果表明,合成的NiCo2O4纳米片直接用作超级电容器电极,呈现出优异的电化学性能。在电流密度为1 m A·cm^-2时,其面积比电容达到1.26 C·cm^-2;经过10000次充放电循环后,其比电容仍能保持初始容量的97.6%。以NiCo2O4纳米片为正极,活性炭为负极组装的超级电容器在功率密度为1.56和4.5 W·cm^-3时,其能量密度分别达到0.14和0.09 Wh·cm^-3。经过10000次循环后,器件仍能保持初始比电容的95%。以上结果证明合成的钴酸镍纳米片电极在未来的储能器件中具有良好的电化学应用前景。展开更多
通过机械球磨制备不同质量比的LCO/NCA混合正极材料,采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)表征其相结构和微观形貌,研究了这种材料的电化学性能。结果表明,两种正极材料球磨混合后其晶体结构均未改变,但是初始的NCA球形二次颗粒...通过机械球磨制备不同质量比的LCO/NCA混合正极材料,采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)表征其相结构和微观形貌,研究了这种材料的电化学性能。结果表明,两种正极材料球磨混合后其晶体结构均未改变,但是初始的NCA球形二次颗粒被打散,形成的纳米粒子弥散填充在LCO微米颗粒的孔隙之间,提高了正极材料的涂膜密度和二者之间的接触紧密性。当LCO:NCA=6:4时混合正极材料具有最佳的颗粒级配效果,其首次充放电效率最高,为92.4%;在10 C (1 C=140 m A·g-1)倍率下的比容量(136 mA·h·g-1)是0.2 C时的78.0%,出现了明显的协同增强效果;在1 C倍率下循环100次其容量保持率为89.8%,表现出优异的电化学性能。展开更多
Aqueous rechargeable zinc-ion batteries(ARZIBs) are expected to replace organic electrolyte batteries owing to its low price,safe and environmentally friendly characteristics.Herein,we fabricated vanadium-based Na1.25...Aqueous rechargeable zinc-ion batteries(ARZIBs) are expected to replace organic electrolyte batteries owing to its low price,safe and environmentally friendly characteristics.Herein,we fabricated vanadium-based Na1.25V3O8 nanosheets as a cathode material for ARZIBs,which present a high performance by electrochemical de-sodium at high voltage to form Na2V6O16 phase in the first cycle:high capacity of 390 mAh/g at 0.1 A/g,high rate perfo rmance(162 mAh/g at 10 A/g) and superior cycle stability(179 mAh/g with a high capacity retention of 88.2% of the maximum capacity after 2000 cycles).In addition,the cell exhibits a high energy density of 416.9 Wh/kg at 143.6 W/kg,suggesting great potential of the as-prepared Na1.25V3O8 nanosheets for ARZIBs.展开更多
A series of layered LiNi0.8?xCo0.1Mn0.1LaxO2(x=0,0.01,0.03)cathode materials were synthesized by combining co-precipitation and high temperature solid state reaction to investigate the effect of La-doping on LiNi0.8Co...A series of layered LiNi0.8?xCo0.1Mn0.1LaxO2(x=0,0.01,0.03)cathode materials were synthesized by combining co-precipitation and high temperature solid state reaction to investigate the effect of La-doping on LiNi0.8Co0.1Mn0.1O2.A new phase La2Li0.5Co0.5O4was observed by XRD,and the content of the new phase could be determined by Retiveld refinement and calculation.The cycle stability of the material is obviously increased from74.3%to95.2%after La-doping,while the initial capacity exhibits a decline trend from202mA·h/g to192mA·h/g.The enhanced cycle stability comes from both of the decrease of impurity and the protection of newly formed La2Li0.5Co0.5O4,which prevents the electrolytic corrosion to the active material.The CV measurement confirms that La-doped material exhibits better reversibility compared with the pristine material.展开更多
对添加不同含量Ti的Mg2Ni-Ti储氢合金进行了电化学腐蚀试验和电化学循环稳定性的测试与分析,结果表明:合金元素Ti的添加,有利于提高Mg2Ni合金的电化学腐蚀性能和电化学循环稳定性。合金中Ti含量以0.8%为宜。与不添加Ti的Mg2Ni储氢合金相...对添加不同含量Ti的Mg2Ni-Ti储氢合金进行了电化学腐蚀试验和电化学循环稳定性的测试与分析,结果表明:合金元素Ti的添加,有利于提高Mg2Ni合金的电化学腐蚀性能和电化学循环稳定性。合金中Ti含量以0.8%为宜。与不添加Ti的Mg2Ni储氢合金相比,添加0.8%Ti时合金的腐蚀电位正移87 m V,放电容量衰减率从86%减小到47%。展开更多
Mg-based hydrogen storage alloys MgNi, Mg0.9Ti0.1Ni, and Mg0.9Ti0.06Zr0.04Ni were successfully prepared by means of mechanical alloying (MA). The structure and the electrochemical characteristics of these Mg-based m...Mg-based hydrogen storage alloys MgNi, Mg0.9Ti0.1Ni, and Mg0.9Ti0.06Zr0.04Ni were successfully prepared by means of mechanical alloying (MA). The structure and the electrochemical characteristics of these Mg-based materials were studied. The X-ray diffraction (XRD) result shows that the main phases of the alloys exhibit amorphous structure. The scanning electron microscopy (SEM) photograph shows that the particle size of Ti and Zr substituted alloys was about 2-4 μm in diameter. The cycle lives of the alloys were prolonged by adding Ti and Zr. After 50 charge-discharge cycles, the discharge capacity of Mg0.9Ti0.06Zr0.04Ni was 91.74% higher than that of MgNi alloy and 37.96% higher than that of Mg0.9Ti0.1Ni alloy. The main reason for the electrode capacity decay is the formation of Mg(OH)2 (product of Mg corrosion) at the surface of alloy. The potentiodynamic polarization result indicates that Ti and Zr doping improves the anticorrosion in an alkaline solution. The electrochemical impedance spectroscopy (EIS) results suggest that proper amount of Ti and Zr doping improves the electrochemical catalytic activity significantly.展开更多
Mg-based hydrogen storage alloys MgNi, Mg0.9Ti0.1Ni and Mg0.9Ti0.1Ni0.9Co0.1 were successfully prepared by means of mechanical alloying (MA). The structure and the electrochemical characteristics of these Mg-based m...Mg-based hydrogen storage alloys MgNi, Mg0.9Ti0.1Ni and Mg0.9Ti0.1Ni0.9Co0.1 were successfully prepared by means of mechanical alloying (MA). The structure and the electrochemical characteristics of these Mg-based materials were also studied. The results of X-ray diffraction (XRD) and scanning electron microscopy (SEM) show that the main phases of the alloys exhibit amorphous structures, and trace of Ni co-exists. The charge-discharge cycle tests indicate these alloys have good electrochemical active characteristics. And the cycle stability of Ti and Co doped alloy was better than that of MgNi alloy. After 50 cycle charge-discharge, the discharge capacity of the Mg0.9Ti0.1Ni0.9Co0.1 alloy was much better than that of MgNi and Mg0.9Ti0.1Ni alloys. The discharge capacity of Mg0.9Ti0.1Ni0.9Co0.1 was 102.8% higher than that of MgNi alloy, and 45.49% higher than that of the Mg0.9Ti0.1Ni alloy. During the process of charge-discharge cycle test, the main reason for the electrode capacity fading is the corrosion of Mg to Mg(OH)2 on the surface of alloys. The Tafel polarization test indicates Ti and Co improve the anticorrosion in an alkaline solution. The EIS results suggest that proper amount of Ti and Co doping improve the electrochemical catalytical activity on the Mg-based alloy surface significantly.展开更多
基金the financial support of National Natural Science Foundation of China (No. 51803062)National Natural Science Foundation of Guangdong Province (No. 2018A030310379)+4 种基金National Postdoctoral Program for Innovation Talents (No. BX201700079)China Postdoctoral Science Foundation Funded Project (No. 2017M620371)and Foundation for Distinguished Young Talents in Higher Education of Guangdong Province (No. 2017KQNCX001)F. Chen thanks the financialsupport of Natural Science Foundation of China (No. 51673175)Natural Science Foundation of Zhejiang Province (Nos. LY16E030012, LY17E030006 and LY18E030009)
文摘Lignin is the most abundant and important macromolecule in organic matter and its yield is second only to cellulose. Lignin is abundant in source, low in price, and has a large number of active groups such as methoxy group and carboxyl group, so it has great utilization value. We used lignin as a carbon source to prepare porous carbon nanosphere(PCN) materials, and in-situ synthesized the MoS_ 2 on its surface. The high specific surface area(462.8 m^2/g), large pore volume and good electron conductivity of the porous carbon scaffold facilitated the reversible electro-chemical reaction of S towards metallic Li, and thus the nano-hybrid showed a high specific energy and excellent cycle stability which still remained 520m Ah/g after 50 cycles.
基金financially sponsored by National Natural Science Foundation of China(51371094 and 51471054)
文摘The RE-Mg-Ni-Mn-based AB2-type La(1-x)CexMgNi(3.5)Mn(0.5)( x = 0- 0. 4) alloys were prepared by spinning treatment. For obtaining the optimum performance,the effects of Ce content and spinning rate on the hydrogen storage performance of the alloys were studied systematically. The results show that the variations of the spinning rate and Ce content result in noteworthy changes of the phase content without altering phase composition of the alloys. Specifically,the LaMgNi4 phase increases and LaNi5 phase decreases when increasing the spinning rate and Ce content. Furthermore,the crystalline grains of Cecontaining alloys prepared by spinning treatment are remarkably refined. The alloys own superior electrochemical performance. All alloys reach the optimal discharge capacity at the initial cycle. Increasing Ce content and spinning rate lead the discharge capacity and electrochemical kinetics rise to an optimal value and then start to reduce. Meanwhile,the electrochemical cycle stability is also improved,which is ascribed to the great enhancement of anti-pulverization and anti-corrosion abilities resulting from the spinning treatment and the substitution of Ce for La.
文摘通过机械球磨制备不同质量比的LCO/NCA混合正极材料,采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)表征其相结构和微观形貌,研究了这种材料的电化学性能。结果表明,两种正极材料球磨混合后其晶体结构均未改变,但是初始的NCA球形二次颗粒被打散,形成的纳米粒子弥散填充在LCO微米颗粒的孔隙之间,提高了正极材料的涂膜密度和二者之间的接触紧密性。当LCO:NCA=6:4时混合正极材料具有最佳的颗粒级配效果,其首次充放电效率最高,为92.4%;在10 C (1 C=140 m A·g-1)倍率下的比容量(136 mA·h·g-1)是0.2 C时的78.0%,出现了明显的协同增强效果;在1 C倍率下循环100次其容量保持率为89.8%,表现出优异的电化学性能。
基金supported by the National Key Research and Development Program of China(No.2017YFB1103000)National Natural Science Foundation of China(Nos.51772193,51702063)+1 种基金Nature Science Fund of Liaoning Province(No.20180550200)the Hong Kong Scholars Programs(No.XJ2019024)。
文摘Aqueous rechargeable zinc-ion batteries(ARZIBs) are expected to replace organic electrolyte batteries owing to its low price,safe and environmentally friendly characteristics.Herein,we fabricated vanadium-based Na1.25V3O8 nanosheets as a cathode material for ARZIBs,which present a high performance by electrochemical de-sodium at high voltage to form Na2V6O16 phase in the first cycle:high capacity of 390 mAh/g at 0.1 A/g,high rate perfo rmance(162 mAh/g at 10 A/g) and superior cycle stability(179 mAh/g with a high capacity retention of 88.2% of the maximum capacity after 2000 cycles).In addition,the cell exhibits a high energy density of 416.9 Wh/kg at 143.6 W/kg,suggesting great potential of the as-prepared Na1.25V3O8 nanosheets for ARZIBs.
基金Project(2014CB643406)supported by the National Basic Research Program of China
文摘A series of layered LiNi0.8?xCo0.1Mn0.1LaxO2(x=0,0.01,0.03)cathode materials were synthesized by combining co-precipitation and high temperature solid state reaction to investigate the effect of La-doping on LiNi0.8Co0.1Mn0.1O2.A new phase La2Li0.5Co0.5O4was observed by XRD,and the content of the new phase could be determined by Retiveld refinement and calculation.The cycle stability of the material is obviously increased from74.3%to95.2%after La-doping,while the initial capacity exhibits a decline trend from202mA·h/g to192mA·h/g.The enhanced cycle stability comes from both of the decrease of impurity and the protection of newly formed La2Li0.5Co0.5O4,which prevents the electrolytic corrosion to the active material.The CV measurement confirms that La-doped material exhibits better reversibility compared with the pristine material.
文摘对添加不同含量Ti的Mg2Ni-Ti储氢合金进行了电化学腐蚀试验和电化学循环稳定性的测试与分析,结果表明:合金元素Ti的添加,有利于提高Mg2Ni合金的电化学腐蚀性能和电化学循环稳定性。合金中Ti含量以0.8%为宜。与不添加Ti的Mg2Ni储氢合金相比,添加0.8%Ti时合金的腐蚀电位正移87 m V,放电容量衰减率从86%减小到47%。
基金Project supported by the National Nature Science Foundation of China (Nos. 50571046, 20573058, 50631020).
文摘Mg-based hydrogen storage alloys MgNi, Mg0.9Ti0.1Ni, and Mg0.9Ti0.06Zr0.04Ni were successfully prepared by means of mechanical alloying (MA). The structure and the electrochemical characteristics of these Mg-based materials were studied. The X-ray diffraction (XRD) result shows that the main phases of the alloys exhibit amorphous structure. The scanning electron microscopy (SEM) photograph shows that the particle size of Ti and Zr substituted alloys was about 2-4 μm in diameter. The cycle lives of the alloys were prolonged by adding Ti and Zr. After 50 charge-discharge cycles, the discharge capacity of Mg0.9Ti0.06Zr0.04Ni was 91.74% higher than that of MgNi alloy and 37.96% higher than that of Mg0.9Ti0.1Ni alloy. The main reason for the electrode capacity decay is the formation of Mg(OH)2 (product of Mg corrosion) at the surface of alloy. The potentiodynamic polarization result indicates that Ti and Zr doping improves the anticorrosion in an alkaline solution. The electrochemical impedance spectroscopy (EIS) results suggest that proper amount of Ti and Zr doping improves the electrochemical catalytic activity significantly.
基金Project supported by the National Natural Science Foundation of China (Nos. 50571046, 50631020 and 20573058) and 863 program (No. 2006AA05Z110).
文摘Mg-based hydrogen storage alloys MgNi, Mg0.9Ti0.1Ni and Mg0.9Ti0.1Ni0.9Co0.1 were successfully prepared by means of mechanical alloying (MA). The structure and the electrochemical characteristics of these Mg-based materials were also studied. The results of X-ray diffraction (XRD) and scanning electron microscopy (SEM) show that the main phases of the alloys exhibit amorphous structures, and trace of Ni co-exists. The charge-discharge cycle tests indicate these alloys have good electrochemical active characteristics. And the cycle stability of Ti and Co doped alloy was better than that of MgNi alloy. After 50 cycle charge-discharge, the discharge capacity of the Mg0.9Ti0.1Ni0.9Co0.1 alloy was much better than that of MgNi and Mg0.9Ti0.1Ni alloys. The discharge capacity of Mg0.9Ti0.1Ni0.9Co0.1 was 102.8% higher than that of MgNi alloy, and 45.49% higher than that of the Mg0.9Ti0.1Ni alloy. During the process of charge-discharge cycle test, the main reason for the electrode capacity fading is the corrosion of Mg to Mg(OH)2 on the surface of alloys. The Tafel polarization test indicates Ti and Co improve the anticorrosion in an alkaline solution. The EIS results suggest that proper amount of Ti and Co doping improve the electrochemical catalytical activity on the Mg-based alloy surface significantly.