Pneumatochemical Immittance Spectroscopy and Pneumatochemical Intermittent Titration Technique for Hydrogen Storage Kinetics

摘要

the invention chemical diffusion coefficient of hydrogen storage materials (hydrogen storage material) (chemical diffusivity, D) How to obtain the qualitative and quantitative reaction kinetics (kinetics) information of a hydrogen storage material, with It provides a method for analysis. In the invention of the pneumatic chemistry emittance spectroscopy (Pneumatochemical Immitacne Spectroscopy, PnIS) in the analysis and pneumatic chemistry intermittent titration (Pneumatochemical Titration Technique, PnITT) on by a hydrogen storage material for the chemical diffusion coefficient and the kinetic information of each frequency range and It provides a method for analysis in the time domain. That determined the time and the frequency range to be analyzed from the PCI hydrogen pressure decay curve and deriving the information theoretical chemical reaction rate and the diffusion coefficient of each hydrogen storage amount (storage of state, SoS). And PnIS assay provides a method for analysis to convert the information in the time domain the Fourier transform to information in the frequency domain, the hydrogen pressure damping aspect is represented by the inductance effect of the frequency domain appears as already locus of the source (inductive loop) in admittance plane it will fit in the equivalent circuit (equivalent circuit), and easy to obtain visually, or by reading the chemical diffusion coefficient and the kinetic information. PnIS result of analysis is was confirmed that the results of the analysis and chemical diffusion coefficient and the kinetic information of the multiple matching PnITT qualitatively and quantitatively. In the embodiment of the present invention, the hydrogen storage material Mg / MgH _{2 was applied to the analysis and PnIS PnITT in} Sievert at 325 degrees from the measuring device of the type Mg / MgH _{2 containing hydrogen pressure damping (relaxation) of information} pressure-composition-isotherms (Pressure-Composition-Isothermal, PCI) Data were obtained. At each point were obtain the effective volume ratio (effective volume ratio) value of , is the linear regression does not have a negative value in the flat section, and issued a mean. The hydrogen pressure decay curve Fourier-Laplace transform (Fourier-Laplace transformation) by, shown by the already locus of the source (inductive loop) of the admittance plane this equivalent model (equivalent circuit) to read chemical diffusing into fittings or visual factors and Kinetic to obtain the information. Mg as compared to MgH ₂ increase differs from the PCI flat section increased diffusion of chemical resistance and identify aspects of chemical diffusion coefficient becomes smaller, which was confirmed following the shrinking-core model. Save time constant and the decay time by fitting the hydrogen pressure the attenuation curves were obtained therefrom to PnITT the chemical diffusion coefficient and diffusion coefficient self (self-diffusivity). As for the hydrogen storage capacity increases in the flat section gradually decreasing the chemical diffusion coefficient and self-diffusion coefficient which is consistent with the results obtained and the qualitative and quantitative analysis to PnIS. ;