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 precursore Zn(en)2S (en=ethylenediamine) were prepared via a solvothermal process from elemental sulfur and zinc using ethylenediamine as a solvent. Detailed characterizations of the infrared (IR) absorption...The precursore Zn(en)2S (en=ethylenediamine) were prepared via a solvothermal process from elemental sulfur and zinc using ethylenediamine as a solvent. Detailed characterizations of the infrared (IR) absorption spectrum, powder X-ray diffraction (XRD) and thermogravimetric analysis (TG) confirmed two en coordinated with Zn2+ to form a complex cation. The morphological property was also characterized by transmission electron microscopy (TEM ) and electron diffraction analysis (ED). Phase-pure hexagonal wurtzite ZnS products were obtained by annealing the precursor in nitrogen stream at about 900 ℃. Zn(en)2S showed a nanosize of about 30 nm, and ZnS of about 60 nm. The fluorescence spectra were also studied. PL results showed that Zn(en)2S excited a fluorescence at 452 nm.展开更多
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.
文摘The precursore Zn(en)2S (en=ethylenediamine) were prepared via a solvothermal process from elemental sulfur and zinc using ethylenediamine as a solvent. Detailed characterizations of the infrared (IR) absorption spectrum, powder X-ray diffraction (XRD) and thermogravimetric analysis (TG) confirmed two en coordinated with Zn2+ to form a complex cation. The morphological property was also characterized by transmission electron microscopy (TEM ) and electron diffraction analysis (ED). Phase-pure hexagonal wurtzite ZnS products were obtained by annealing the precursor in nitrogen stream at about 900 ℃. Zn(en)2S showed a nanosize of about 30 nm, and ZnS of about 60 nm. The fluorescence spectra were also studied. PL results showed that Zn(en)2S excited a fluorescence at 452 nm.