The TiNiHf alloys are newly developed as high temperature shape memory alloys with the high transformation temperatures and with lower cost in comparison with TiNiX (X 5 Pd, Pt) alloys. Recently a lot of investigations were focused on the TiNiHf alloys, in which Hf contents are ranged from 1% to 30% [1–8]. Zhu et al. [9] proposed that the decrease of the transformation temperatures of the Ti51....

Ambient pressure photoelectron and absorption spectroscopies were applied under 0.2 mbar of O2 and H2 to establish an unequivocal correlation between the surface oxidation state of extended and nanosized PtCo alloys and the gas-phase environment. Fundamental differences in the electronic structure and reactivity of segregated cobalt oxides were associated with surface stabilization of metastabl...

CoPt equiatomic alloy orders according to the tetragonal L1(0) structure which favors strong magnetic anisotropy. Conversely, magnetism can influence the chemical ordering. We present here ab initio calculations of the stability of the L1(0) and L1(2) structures of Co-Pt alloys in their paramagnetic and ferromagnetic states. They show that magnetism strongly reinforces the ordering tendencies i...

Decreasing the cost associated with platinum-based catalysts along with improving their catalytic properties is a major challenge for commercial direct methanol fuel cells. In this work, a simple and facile strategy was developed for the more efficient preparation of multi-walled carbon nanotube (MWCNT) -supported Pt/CoPt composite nanoparticles (NPs) via solution plasma sputtering with subsequ...

In the past, the modeling of catalytic processes was limited by the size and complexity of the systems involved. However, the enormous progress in both computer power and theoretical methods has made computational modeling a valuable tool in increasing our knowledge of catalytic reactions on the atomic scale. While complex reactions can be studied by dividing the overall reaction into a series ...

In situ x-ray absorption spectroscopy (XAS) in 1 M HC1O4 was used to examine the electronic and structural effects of hydrogen adsorption on carbon supported Pt (Pt/C) and Pt alloyed with first row transition metals (Cr, Mn, Fe, Co, and Ni). In the case of Pt/C, potential excursions from the double layer region (0.54 V vs. RHE) to 0.0 V caused significant changes in the XAS spectra whereas none...

Alloys are beneficial in numerous applications since they combine the desirable properties of different metals. In this regard, Pt/Pd alloys have been investigated as a replacement for Pt, which is standard catalyst used various catalytic processes. However, there still gaps our understanding structural, mechanical, and thermodynamic alloys. This study was conducted using density functional the...

Alloys of platinum and rhodium are extensively used in thermocouples for high-temperature measurement and as clean and inert heating elements in experimental high-temperature furnaces. The phase diagram for the Pt-Rh system is inadequately characterized.[1] The liquidus has been measured by Müller[2] and Acken.[3] The results have been normalized using more recent values for the melting points ...