Abstract

In the Mo–Si binary system, Mo₅Si₃ crystallizes in the W₅Si₃ (T₁ phase) structure type. However, when boron replaces silicon in this compound, a structural transition occurs from the W₅Si₃ prototype structure to the Cr₅B₃ prototype structure (T₂ phase) at the composition Mo₅SiB₂. Mo₅SiB₂ has received much attention in the literature as a candidate for structural application in high-temperature turbines, but its electronic and magnetic behavior has not been explored. In this work, we show that Mo₅SiB₂ is a bulk superconducting material with critical temperature close to 5.8 K. The specific-heat, resistivity and magnetization measurements reveal that this material is a conventional type II BCS superconductor.

Highlights

► In this work, the structural, magnetic, electronic transport and specific-heat properties have been investigated in Mo₅SiB₂. ► The data showed unambiguously that the polycrystalline Mo₅SiB₂ compound is a bulk superconductor at . ► This apparent divergence between DOS at Fermi level and T_c may be related to a possible Van Hove singularity. ► Cr₅B₃ prototype is a promising structure for superconductivity and other compounds with same the prototype should be investigated.