通过电化学剥离协同制备了3D Ni(OH)_(2)/石墨烯复合电极薄膜材料,高品质石墨烯均匀地生长在三维Ni(OH)_(2)表面,电化学性能测试表明,在2 m A/cm^(2)电流密度条件下,该电极薄膜具有优异的比电容(266 m F/cm^(2)),经过1万次的连续充放电...通过电化学剥离协同制备了3D Ni(OH)_(2)/石墨烯复合电极薄膜材料,高品质石墨烯均匀地生长在三维Ni(OH)_(2)表面,电化学性能测试表明,在2 m A/cm^(2)电流密度条件下,该电极薄膜具有优异的比电容(266 m F/cm^(2)),经过1万次的连续充放电循环测试仍然保留94.1%的容量性能。该方法为大规模生产新型高性能电极薄膜材料提供了一个简单的制备策略。展开更多
Exploring a novel strategy for large-scale production of battery-type Ni(OH)_(2)-based composites,with excellent capacitive performance,is still greatly challenging.Herein,we developed a facile and cost-effective stra...Exploring a novel strategy for large-scale production of battery-type Ni(OH)_(2)-based composites,with excellent capacitive performance,is still greatly challenging.Herein,we developed a facile and cost-effective strategy to in situ grow a layer of Ni(OH)_(2)/Ti_(3)C_(2)T_(x)composite on the nickel foam(NF)collector,where Ti_(3)C_(2)T_(x)is not only a conductive component,but also a catalyst that accelerates the oxidation of NF to Ni(OH)_(2).Detailed analysis reveals that the crystallinity,morphology,and electronic structure of the integrated electrode can be tuned via the electrochemical activation,which is beneficial for improving electrical conductivity and redox activity.As expected,the integrated electrode shows a specific capacity of 1.09 C cm^(-2)at 1 mA cm^(-2)after three custom activation cycles and maintains 92.4%of the initial capacity after 1500 cycles.Moreover,a hybrid supercapacitor composed of Ni(OH)_(2)/Ti_(3)C_(2)T_(x)/NF cathode and activated carbon anode provides an energy density of 0.1 mWh cm^(-2)at a power density of 0.97 mW cm^(-2),and excellent cycling stability with about 110%capacity retention rate after 5000 cycles.This work would afford an economical and convenient method to steer commercial Ni foam into advanced Ni(OH)_(2)-based composite materials as binder-free electrodes for hybrid supercapacitors.展开更多
Two-dimensional (2D)Ni(OH)_(2) nanosheets can theoretically expose their active sites of 100%.Whereas,their intrinsic easy accumulation and low conductivity lead to weak and unsustainable reaction kinetics.Herein,we p...Two-dimensional (2D)Ni(OH)_(2) nanosheets can theoretically expose their active sites of 100%.Whereas,their intrinsic easy accumulation and low conductivity lead to weak and unsustainable reaction kinetics.Herein,we propose a novel halogen chlorine-triggered electrochemical etching strategy to controllably manage the reaction kinetics of 2D Ni(OH)_(2) nanosheets(EE/Cl-Ni(OH)_(2)).It is found that halogen chlorine doping can adjust the interlamellar spacing flexibly and promote the lattice oxygen activation to achieve controlled construction of superficial oxygen defects at the adjustable voltage.The optimal EE/Cl-Ni(OH)_(2) electrode exhibits a high rate capability and excellent specific capacity of 206.9 mA h g^(-1) at 1 A g^(-1) in a three-electrode system,which is more than twice as high as the pristine Ni(OH)_(2).Furthermore,EE/Cl-Ni(OH)_(2) cathode and FeOOH@rGO anode are employed for developing an aqueous Ni-Fe battery with an excellent energy density of 83 W h kg^(-1),a high power density of 17051 W kg^(-1),and robust durability over 20,000 cycles.This strategy exploits a fresh channel for the ingenious fabrication of highefficiency and stable nickel-based deficiency materials for energy storage.展开更多
The influence of transforming pH values on the electrochemical performance of nano-scale Ni （OH）2 was analyzed. The measurement results of XRD indicate that the nano-scale Ni （OH） 2 prepared at different transform...The influence of transforming pH values on the electrochemical performance of nano-scale Ni （OH）2 was analyzed. The measurement results of XRD indicate that the nano-scale Ni （OH） 2 prepared at different transformations of pH value is β （ Ⅱ ）-phase with different crystal lattice parameters. Cyclic voltammograms （CV） and electrochemical impedance spectroscopy（EIS） measurement results show that transformations of pH value affect the proton diffusion coefficient （D） and charge-transfer resistance （Re,） of the material. The simulation of.cell experiment shows that the sample prepared at a pH of 10. 1 exhibits the maximum specific capacity （327.8 mAh/g） and higher discharge platform, the discharge performance of electrodes depends on both D and Rct, so the kinetics characteristics that electrodes reaction is controlled by both mass-transfer step and charge- transfer step are put forward.展开更多
The influence of transformation pH value on the performance of nano-scale Ni(OH)2 was analyzed. The measurement results of XRD and TEM indicate that the samples are composed of β-Ni(OH)2 with crystal size of 20-50 nm...The influence of transformation pH value on the performance of nano-scale Ni(OH)2 was analyzed. The measurement results of XRD and TEM indicate that the samples are composed of β-Ni(OH)2 with crystal size of 20-50 nm, and the crystal lattice parameters of nano-scale Ni(OH)2 prepared at different transformation pH values are different. With the increase of transformation pH value, the agglomeration of nano-scale Ni(OH)2 becomes obvious. Cyclic voltammograms(CV) and electrochemical impedance spectroscopy(EIS) measurement results show that transformation pH value affects the proton diffusion coefficient(D) and charge-transfer resistance(Rct) of the material. The specific capacity is up to 327.8 mA·h/g, and the discharge performance of electrodes depends on both D and Rct, so the kinetic characteristics that electrodes reaction is controlled by both mass-transfer step and charge-transfer step was put forward.展开更多
文摘通过电化学剥离协同制备了3D Ni(OH)_(2)/石墨烯复合电极薄膜材料,高品质石墨烯均匀地生长在三维Ni(OH)_(2)表面,电化学性能测试表明,在2 m A/cm^(2)电流密度条件下,该电极薄膜具有优异的比电容(266 m F/cm^(2)),经过1万次的连续充放电循环测试仍然保留94.1%的容量性能。该方法为大规模生产新型高性能电极薄膜材料提供了一个简单的制备策略。
基金supported by the NSF of China(Nos.21971143,21805165,22209098)the 111 Project(D20015)+1 种基金the major research and development project of Hubei Three Gorges Laboratory(2022-3)the Natural Science Foundation of Hubei Province(2022CFB326)
文摘Exploring a novel strategy for large-scale production of battery-type Ni(OH)_(2)-based composites,with excellent capacitive performance,is still greatly challenging.Herein,we developed a facile and cost-effective strategy to in situ grow a layer of Ni(OH)_(2)/Ti_(3)C_(2)T_(x)composite on the nickel foam(NF)collector,where Ti_(3)C_(2)T_(x)is not only a conductive component,but also a catalyst that accelerates the oxidation of NF to Ni(OH)_(2).Detailed analysis reveals that the crystallinity,morphology,and electronic structure of the integrated electrode can be tuned via the electrochemical activation,which is beneficial for improving electrical conductivity and redox activity.As expected,the integrated electrode shows a specific capacity of 1.09 C cm^(-2)at 1 mA cm^(-2)after three custom activation cycles and maintains 92.4%of the initial capacity after 1500 cycles.Moreover,a hybrid supercapacitor composed of Ni(OH)_(2)/Ti_(3)C_(2)T_(x)/NF cathode and activated carbon anode provides an energy density of 0.1 mWh cm^(-2)at a power density of 0.97 mW cm^(-2),and excellent cycling stability with about 110%capacity retention rate after 5000 cycles.This work would afford an economical and convenient method to steer commercial Ni foam into advanced Ni(OH)_(2)-based composite materials as binder-free electrodes for hybrid supercapacitors.
基金supported by the Opening Project of State Key Laboratory of Advanced Chemical Power Sourcesthe Guizhou Provincial Science and Technology Projects(QKHJC-ZK[2021]YB057)+1 种基金the Growth Project of Young Scientific and Technological Talents in Colleges and Universities of Guizhou Province(QKHJCKYZ[2021]252)the Reward and Subsidy Fund Project of Guizhou Education University(Z20210108)。
文摘Two-dimensional (2D)Ni(OH)_(2) nanosheets can theoretically expose their active sites of 100%.Whereas,their intrinsic easy accumulation and low conductivity lead to weak and unsustainable reaction kinetics.Herein,we propose a novel halogen chlorine-triggered electrochemical etching strategy to controllably manage the reaction kinetics of 2D Ni(OH)_(2) nanosheets(EE/Cl-Ni(OH)_(2)).It is found that halogen chlorine doping can adjust the interlamellar spacing flexibly and promote the lattice oxygen activation to achieve controlled construction of superficial oxygen defects at the adjustable voltage.The optimal EE/Cl-Ni(OH)_(2) electrode exhibits a high rate capability and excellent specific capacity of 206.9 mA h g^(-1) at 1 A g^(-1) in a three-electrode system,which is more than twice as high as the pristine Ni(OH)_(2).Furthermore,EE/Cl-Ni(OH)_(2) cathode and FeOOH@rGO anode are employed for developing an aqueous Ni-Fe battery with an excellent energy density of 83 W h kg^(-1),a high power density of 17051 W kg^(-1),and robust durability over 20,000 cycles.This strategy exploits a fresh channel for the ingenious fabrication of highefficiency and stable nickel-based deficiency materials for energy storage.
基金the National Natural Science Foundation of China (Grant No.20271015)
文摘The influence of transforming pH values on the electrochemical performance of nano-scale Ni （OH）2 was analyzed. The measurement results of XRD indicate that the nano-scale Ni （OH） 2 prepared at different transformations of pH value is β （ Ⅱ ）-phase with different crystal lattice parameters. Cyclic voltammograms （CV） and electrochemical impedance spectroscopy（EIS） measurement results show that transformations of pH value affect the proton diffusion coefficient （D） and charge-transfer resistance （Re,） of the material. The simulation of.cell experiment shows that the sample prepared at a pH of 10. 1 exhibits the maximum specific capacity （327.8 mAh/g） and higher discharge platform, the discharge performance of electrodes depends on both D and Rct, so the kinetics characteristics that electrodes reaction is controlled by both mass-transfer step and charge- transfer step are put forward.
基金Project(20271015) supported by the National Natural Science Foundation of China
文摘The influence of transformation pH value on the performance of nano-scale Ni(OH)2 was analyzed. The measurement results of XRD and TEM indicate that the samples are composed of β-Ni(OH)2 with crystal size of 20-50 nm, and the crystal lattice parameters of nano-scale Ni(OH)2 prepared at different transformation pH values are different. With the increase of transformation pH value, the agglomeration of nano-scale Ni(OH)2 becomes obvious. Cyclic voltammograms(CV) and electrochemical impedance spectroscopy(EIS) measurement results show that transformation pH value affects the proton diffusion coefficient(D) and charge-transfer resistance(Rct) of the material. The specific capacity is up to 327.8 mA·h/g, and the discharge performance of electrodes depends on both D and Rct, so the kinetic characteristics that electrodes reaction is controlled by both mass-transfer step and charge-transfer step was put forward.
