No abstract

Concentrated solid solution alloys (CSAs) -including high entropy alloys (HEAs)are known for their remarkable mechanical and corrosion resistances with superior tolerance against the deleterious effect of irradiation exposure when compared with pure metals and dilute alloys. To date, however, the mechanisms responsible for such improvements are still unclear and remain a subject of investigation. The present work reports in situ Transmission Electron Microscopy (TEM) study under simultaneous ion irradiation of the face-centred cubic (FCC) FeCrMnNi quaternary HEA, comparing with a non-equiatomic Fe-based alloy, the AISI-348 austenitic stainless steel that has Cr, Ni and Mn as alloying elements. The alloys were irradiated under the same conditions, with 6 keV He + and 134 keV Xe + ions at 298 K up to 1.7×10 17 ions•cm −2 (4 displacements per atom, dpa) and 2.7×10 15 ions•cm −2 (4 dpa), respectively. The nucleation of inert gas bubbles was tracked upon post-irradiation extended annealing up to 673 K. He and Xe bubbles were observed to grow at a rate slightly slower in the equiatomic alloy. Trends from the bubble size analyses show that the nucleation and growth of inert gas bubbles are suppressed or delayed in some conditions in the nearly equiatomic alloy.

In our work, MoS 2 /graphene/MOF hybrid materials were synthesized via a two-step process consisting of the plasma-assisted electrochemical preparation of MoS 2 /graphene and the wet formation of Cu-based metal-organic framework (MOF). The hybrid materials were characterized with Field Emission Scanning Electron Microscopy, High-Resolution Transmission Electron Microscopy, X-ray Diffraction and Raman Spectroscopy. Furthermore, some initial results on their electrochemical properties for hydrogen evolution and oxygen evolution reactions were also presented, showing the potential to be a bi-functional catalyst.