Nickel hydroxide was used as the positive electrode material in rechargeable alkaline batteries, which plays a significant role in the field of electric energy storage devices. β-nickel hydroxide（β-Ni（OH）2 ） was...Nickel hydroxide was used as the positive electrode material in rechargeable alkaline batteries, which plays a significant role in the field of electric energy storage devices. β-nickel hydroxide（β-Ni（OH）2 ） was prepared from nickel sulphate solution using potassium hydroxide as a precipitating agent. Pure β-phase of nickel hydroxide was confirmed from XRD and FT-IR studies. The effects of TiO2 additive on the β-Ni（OH）2 electrode performance are examined. The structure and property of the TiO2 added β-Ni（OH）2 were characterized by XRD, TG-DTA and SEM analysis. A pasted–type electrode is prepared using nickel hydroxide powder as the main active material on a nickel sheet as a current collector. Cyclic voltammetry and electrochemical impedance spectroscopy studies were performed to evaluate the electrochemical performance of the β-Ni（OH）2 and TiO2 added β-Ni（OH）2 electrodes in 6 M KOH electrolyte. Anodic（Epa） and cathodic（Epc）peak potentials are found to decrease after the addition of TiO 2 into β-Ni（OH）2 electrode material. Further,addition of TiO2 is found to enhance the reversibility of the electrode reaction and also increase the separation of the oxidation current peak of the active material from the oxygen evolution current. Compared with pure β-Ni（OH）2 lectrode,TiO2 added β-Ni（OH）2 electrode is found to exhibit higher proton diffusion coefficient（D） and lower charge transfer resistance. These findings suggest that the TiO2 added β-Ni（OH）2 electrode possess improved electrochemical properties and thus can be recognized as a promising candidate for the battery electrode applications.展开更多
The electrode materials as the key component of supercapacitors have attracted considerable research interests, especially for nickel/cobalt based materials by virtue of their superior electrochemical performance with...The electrode materials as the key component of supercapacitors have attracted considerable research interests, especially for nickel/cobalt based materials by virtue of their superior electrochemical performance with multiple oxidation states for richer redox reactions, abundant natural resources, lower prices and toxicity. There are many advanced electrodes based on the nickel/cobalt materials exploited for the application of supercapacitors, however, some controversial statements have induced some confusion. Herein, we refine the mechanism of energy storage for the nickel/cobalt based materials for supercapacitors and reclassify them into battery-type materials with the corresponding devices named as hybrid supercapacitors.展开更多
Ultra-high nickel material is considered to be a promising cathode material.However,with the increase of nickel content,the interfacial side reactions between the cathode and electrolyte become increasingly serious.He...Ultra-high nickel material is considered to be a promising cathode material.However,with the increase of nickel content,the interfacial side reactions between the cathode and electrolyte become increasingly serious.Herein,an atomically controllable ionic conductor Li_(3)PO_(4)(LPO)coating is deposited on the LiNi_(0.90)Co_(0.06)Mn_(0.04)O_(2)(NCM9064)based electrode by the atomic layer deposition method.The results shows that the LPO coating is uniformly and densely covered on the surface of secondary particles of NCM9064,helping to prevent the direct contact between the electrolyte and cathode during the chargingdischarging process.In addition,the coating layer is electrochemically stable.As a result,the interfacial side reactions during the long cycle are effectively suppressed,and the solid electrolyte interphase layer at the interface is stabilized.The electrode with 20 layers of LPO deposition(ALD-LPO-20)exhibits an excellent capacity retention of 81%after 200 cycles in 2.8-4.3 V at 25℃,which is 18%higher than the unmodified material(ALD-LPO-0).Besides,the moderate LPO coating improves the rate capability and high temperature cycling performance of NCM9064.This study provides a method for the modification of ultra-high nickel cathode materials and corresponding electrodes.展开更多
Ultra-high nickel layered oxide cathode material with high energy density is the most promising material to improve the electrochemical performance of lithium-ion batteries(LIBs).However,the poor structural stability ...Ultra-high nickel layered oxide cathode material with high energy density is the most promising material to improve the electrochemical performance of lithium-ion batteries(LIBs).However,the poor structural stability and severe surface/interface side reactions of the material lead to poor rate performance and cyclic stability,which limits its application in practice.In this paper,the dual-modification strategy of Co doping and La_(2)O_(3) coating is used to meet the above challenges.Co doping can effectively widen layer spacing and reduce Li^(+)/Ni^(2+) mixing,and La_(2)O_(3) coating can effectively eliminate the residual alkali on the surface of active material,inhibit the thickening of cathode electrolyte interphase(CEI)film and reduce surface/interface side reactions.Therefore,the modified material(NM90-CL)with excellent electrochemical properties is achieved through the synergistic enhancement of Co doping and La_(2)O_(3) coating.Its capacity retention rate can reach 77.9%after 200 cycles at 1.0℃ and 75.7%after 200 cycles at 5.0℃.Its reversible capacity can up to 153.5 mAh·g^(–1) at 10.0℃.This dual-modification strategy will provide theoretical guidance and technical support for the synthesis of other high-performance electrode materials.展开更多
Hierarchical flower-like architectures of[Ni_3（BTC）_2·12H_2O]（BTC^3=benzene-1,3,5-tricarboxylate） were successfully prepared by a simple solution-phase method under mild conditions without any template or sur...Hierarchical flower-like architectures of[Ni_3（BTC）_2·12H_2O]（BTC^3=benzene-1,3,5-tricarboxylate） were successfully prepared by a simple solution-phase method under mild conditions without any template or surfactant.Phase-pure porous NiO nanocrystals were obtained by annealing the Ni-BTC complex without significant alteration in morphology.The product was characterized by X-ray diffraction techniques,field-emission scanning electron microscopy（FESEM）.transmission electron microscopy（TEM） and high-resolution TEM（HRTEM）.The catalytic effect of the NiO product was investigated on the thermal decomposition of ammonium perchlorate（AP） and it was found that the annealed NiO product has higher catalytic activity than the commercial NiO.展开更多
文摘Nickel hydroxide was used as the positive electrode material in rechargeable alkaline batteries, which plays a significant role in the field of electric energy storage devices. β-nickel hydroxide（β-Ni（OH）2 ） was prepared from nickel sulphate solution using potassium hydroxide as a precipitating agent. Pure β-phase of nickel hydroxide was confirmed from XRD and FT-IR studies. The effects of TiO2 additive on the β-Ni（OH）2 electrode performance are examined. The structure and property of the TiO2 added β-Ni（OH）2 were characterized by XRD, TG-DTA and SEM analysis. A pasted–type electrode is prepared using nickel hydroxide powder as the main active material on a nickel sheet as a current collector. Cyclic voltammetry and electrochemical impedance spectroscopy studies were performed to evaluate the electrochemical performance of the β-Ni（OH）2 and TiO2 added β-Ni（OH）2 electrodes in 6 M KOH electrolyte. Anodic（Epa） and cathodic（Epc）peak potentials are found to decrease after the addition of TiO 2 into β-Ni（OH）2 electrode material. Further,addition of TiO2 is found to enhance the reversibility of the electrode reaction and also increase the separation of the oxidation current peak of the active material from the oxygen evolution current. Compared with pure β-Ni（OH）2 lectrode,TiO2 added β-Ni（OH）2 electrode is found to exhibit higher proton diffusion coefficient（D） and lower charge transfer resistance. These findings suggest that the TiO2 added β-Ni（OH）2 electrode possess improved electrochemical properties and thus can be recognized as a promising candidate for the battery electrode applications.
基金supported by the National Natural Science Foundation of China(No.51672109)Natural Science Foundation of Shandong Province for Excellent Young Scholars(No.ZR2016JL015)
文摘The electrode materials as the key component of supercapacitors have attracted considerable research interests, especially for nickel/cobalt based materials by virtue of their superior electrochemical performance with multiple oxidation states for richer redox reactions, abundant natural resources, lower prices and toxicity. There are many advanced electrodes based on the nickel/cobalt materials exploited for the application of supercapacitors, however, some controversial statements have induced some confusion. Herein, we refine the mechanism of energy storage for the nickel/cobalt based materials for supercapacitors and reclassify them into battery-type materials with the corresponding devices named as hybrid supercapacitors.
基金supported by the National Natural Science Foundation of China(No.52174285)the Science and Technology Innovation Program of Hunan Province(No.2022RC3048)+1 种基金the Key Research and Development Program of Yunnan Province(No.202103AA080019)the Research Foundation of Education Bureau of Hunan Province(No.18B477).
文摘Ultra-high nickel material is considered to be a promising cathode material.However,with the increase of nickel content,the interfacial side reactions between the cathode and electrolyte become increasingly serious.Herein,an atomically controllable ionic conductor Li_(3)PO_(4)(LPO)coating is deposited on the LiNi_(0.90)Co_(0.06)Mn_(0.04)O_(2)(NCM9064)based electrode by the atomic layer deposition method.The results shows that the LPO coating is uniformly and densely covered on the surface of secondary particles of NCM9064,helping to prevent the direct contact between the electrolyte and cathode during the chargingdischarging process.In addition,the coating layer is electrochemically stable.As a result,the interfacial side reactions during the long cycle are effectively suppressed,and the solid electrolyte interphase layer at the interface is stabilized.The electrode with 20 layers of LPO deposition(ALD-LPO-20)exhibits an excellent capacity retention of 81%after 200 cycles in 2.8-4.3 V at 25℃,which is 18%higher than the unmodified material(ALD-LPO-0).Besides,the moderate LPO coating improves the rate capability and high temperature cycling performance of NCM9064.This study provides a method for the modification of ultra-high nickel cathode materials and corresponding electrodes.
基金This work was financially supported by the National Science Foundation of China(Nos.22169007 and 22362011)the Science and Technology Major Project of Guangxi(No.AA19046001)+3 种基金the Open Research Fund of Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials(Nos.EMFM20201105 and EMFM20181119)the Characteristic Innovation Projects of Universities in Guangdong Province(No.2022KTSCX324)the Science and Technology Innovation Commission of Shenzhen(No.JCYJ20190808173815205)the University Teachers'Characteristic Innovation Research Project(No.2021XJZZ11).
文摘Ultra-high nickel layered oxide cathode material with high energy density is the most promising material to improve the electrochemical performance of lithium-ion batteries(LIBs).However,the poor structural stability and severe surface/interface side reactions of the material lead to poor rate performance and cyclic stability,which limits its application in practice.In this paper,the dual-modification strategy of Co doping and La_(2)O_(3) coating is used to meet the above challenges.Co doping can effectively widen layer spacing and reduce Li^(+)/Ni^(2+) mixing,and La_(2)O_(3) coating can effectively eliminate the residual alkali on the surface of active material,inhibit the thickening of cathode electrolyte interphase(CEI)film and reduce surface/interface side reactions.Therefore,the modified material(NM90-CL)with excellent electrochemical properties is achieved through the synergistic enhancement of Co doping and La_(2)O_(3) coating.Its capacity retention rate can reach 77.9%after 200 cycles at 1.0℃ and 75.7%after 200 cycles at 5.0℃.Its reversible capacity can up to 153.5 mAh·g^(–1) at 10.0℃.This dual-modification strategy will provide theoretical guidance and technical support for the synthesis of other high-performance electrode materials.
基金financially supported by the National Natural Science Foundation of China(Nos.91122001 and 21021062)the National Basic Research Program of China(No. 2010CB923303)
文摘Hierarchical flower-like architectures of[Ni_3（BTC）_2·12H_2O]（BTC^3=benzene-1,3,5-tricarboxylate） were successfully prepared by a simple solution-phase method under mild conditions without any template or surfactant.Phase-pure porous NiO nanocrystals were obtained by annealing the Ni-BTC complex without significant alteration in morphology.The product was characterized by X-ray diffraction techniques,field-emission scanning electron microscopy（FESEM）.transmission electron microscopy（TEM） and high-resolution TEM（HRTEM）.The catalytic effect of the NiO product was investigated on the thermal decomposition of ammonium perchlorate（AP） and it was found that the annealed NiO product has higher catalytic activity than the commercial NiO.
