A promising $p$-type transparent conducting material: Layered oxysulfide $\left[{\mathrm{Cu}}_2{\mathrm{S}}_2\right]\left[{\mathrm{Sr}}_3{\mathrm{Sc}}_2{\mathrm{O}}_5\right]$

${\mathrm{Sr}}_3{\mathrm{Cu}}_2{\mathrm{Sc}}_2{\mathrm{O}}_5{\mathrm{S}}_2$, a layered oxysulfide, composed of anti-PbO-like $\left[{\mathrm{Cu}}_2{\mathrm{S}}_2\right]$ slabs alternating with perovskitelike $\left[{\mathrm{Sr}}_3{\mathrm{Sc}}_2{\mathrm{O}}_5\right]$ slabs, was systematically studied as a $p$-type transparent conducting material. The material has a wide energy gap of $3.1\mathrm{eV}$ and a $p$-type electrical conductivity of $2.8\mathrm{S}{\mathrm{cm}}^{-1}$ at room temperature. The hole mobility of $+150{\mathrm{cm}}^2{\mathrm{V}}^{-1}{\mathrm{S}}^{-1}$ at room temperature, which is much higher than the typical value of $\sim {10}^{-1}–10{\mathrm{cm}}^2{\mathrm{V}}^{-1}{\mathrm{S}}^{-1}$ found in other copper compounds. The performances of bulk undoped ${\mathrm{Sr}}_3{\mathrm{Cu}}_2{\mathrm{Sc}}_2{\mathrm{O}}_5{\mathrm{S}}_2$ show the promise of copper oxysulfides as a class of $p$-type transparent conductive materials that is essential for optoelectronic applications.