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 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
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
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.
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.
