Synthesis and high temperature transport properties of new quaternary layered selenide NaCuMnSe2

• A new quaternary layered selenide NaCuMnSe2 is synthesized.
• All the compositions show semiconducting nature, whereas the Seebeck coefficient increases gradually over the entire measured temperature range.
• Conduction mechanism transforms from thermally activated behavior to 2D variable range hopping with increase in copper concentration.

Synthesis and high temperature transport properties of NaCu1+xMn1−xSe2, (x=0−0.75) a new quaternary layered selenide, are reported. NaCuMnSe2 crystallizes in a trigonal unit cell with space group of P-3m1 (a=4.1276 Å, c=7.1253 Å). The isovalent substitution of Mn2+ by Cu2+ is carried out. All the compositions show semiconducting nature, whereas the Seebeck coefficient increases gradually over the entire measured temperature range. Compositions with x=0 and 0.025 follow thermally activated behavior. With increase in copper concentration the conduction mechanism transforms to 2D variable range hopping (VRH) for x=0.05 and 0.075.

Crystal structure of NaCuMnSe2.Figure optionsDownload as PowerPoint slide