Effect on electrical and magnetic behavior of Al-Cu-Fe quasicrystals during surface leaching

In this study, the effect of change in electric and magnetic characteristics of Al-Cu-Fe quasicrystals (QCs), by de-alloying of Al from the surface, was investigated. Dissolution of Al was carried out in NaOH aqueous solution which did not change the icosahedral structure of Al-Cu-Fe; however, it changed the non-magnetic nature of Al-Cu-Fe QCs into the ferromagnetic one. This has never been reported in previous studies on Al-Cu-Fe QCs. The ferromagnetic characteristics of icosahedral Al-Cu-Fe QCs powder (at room temperature and 5 K) were studied in detail using vibrating sample magnetometer (VSM). For the first time, it is reported that the value of susceptibility (chi(m)) of Al-Cu-Fe QCs was in the order of 10(3) which is considerably greater then chi(m) value of diamagnetic and paramagnetic materials. The VSM data indicate that approximately approximate to 1.5% of the total Fe atoms in icosahedral Al-Cu-Fe QC contribute to magnetism and most of which comes from the leached icosahedral surface. Further, Mossbauer spectroscopy (MS) results of Al-Cu-Fe QC powder samples confirm the presence of high spin Fe3+ ionic state. Linear lines of current-voltage (I-V) graph indicate the Ohmic behavior of samples before and after leaching process.

Automated summary

In this study, the change in electric and magnetic characteristics of Al-Cu-Fe quasicrystals by de-alloying of Al from the surface was investigated. The ferromagnetic nature of Al-Cu-Fe QCs was observed after the dissolution of Al in NaOH solution. Mössbauer spectroscopy confirmed the presence of high spin Fe3+ ionic state in the samples.