Influences of heat treatment on the structure and electrochemical properties of Mg0.9Ti0.1Ni hydrogen storage alloys

Abstract

Neste trabalho, os efeitos do tratamento térmico nas estruturas e propriedades eletroquímicas de ligas para armazenamento de hidrogênio Mg 0.9 Ti 0.1 Ni foram investigadas em detalhe. As análises por difração de raios-X (XRD) e microscopia eletrônica (SEM) mostraram que as amostras exibiram predominantemente uma estrutura amorfa. Estudos eletroquímicos revelaram que o tratamento térmico pode melhorar a capacidade máxima de descarga e ciclabilidade dos eletrodos desta liga. O valor de C max à liga Mg 0.9 Ti 0.1 Ni preparada por moagem, foi de apenas 229,9 mAh g -1 ; entretanto, o valor atingiu 331,9 mAh g -1 após o tratamento térmico a 873K por 8 h seguido de moagem. A voltametria cíclica, espectroscopia de impedância eletroquímica e polarização potenciodinâmica indicaram que o tratamento térmico não só aumentou a capacidade de descarga, mas também melhorou a cinética de carga/descarga da liga Mg 0.9 Ti 0.1 Ni.In the present study, the effects of heat treatment on the structures and electrochemical properties of Mg 0.9 Ti 0.1 Ni hydrogen storage alloys have been investigated in detail. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses showed that the samples exhibited a predominantly amorphous structure. Electrochemical investigations revealed that heat treatment can improve the maximum discharge capacity and cyclic stability of the alloy electrodes. For Mg 0.9 Ti 0.1 Ni alloy prepare by ball milling, the value of C max was only 229.9 mAh g -1 , however, the value reached 331.9 mAh g -1 after heat treatment at 873K for 8 h and then milling. The cycle voltammetry, electrochemical impedance spectroscopy and potentiodynamic polarization indicated that heat treatment not only increased the discharge capacity but also improved the charge/discharge kinetics of Mg 0.9 Ti 0.1 Ni alloy.

Synthesis of iron sulfide thin films and powders from new xanthate precursors

“…[11][12][13][14] This material has been researched for a range of applications such as commercial lithium ion cells, solar cells and for catalysis. [15][16][17][18] Furthermore, it has also been used in optoelectronic devices, storage devices, energy conversion and biomedical applications. 19,20 Nanostructured pyrite has been produced with control of morphology, phases and size which are strongly influenced by reaction parameters such as precursor type, deposition temperature and synthesis method.…”