In situ neutron diffraction study on the deformation behavior of the plastic inorganic semiconductor Ag2S

Bulk Ag2S is a plastic inorganic semiconductor at room temperature. It exhibits a compressive strain greater than 50%, which is highly different from brittle conventional counterparts, such as silicon. Here, we present the experimental investigation of the deformation behavior in a plastic inorganic semiconductor Ag2S using in situ neutron diffraction during compressive deformation at room and elevated temperatures. At room temperature, the lattice strain partitioning among hkl-orientated grain families could be responsible for the significant work-hardening behavior in the bulk Ag2S with a monoclinic structure. The rapid accumulation of lattice defects and remarkable development of the deformation texture suggest that dislocation slip promotes plasticity. At 453 K, a monoclinic phase transforms into a body-centered cubic phase. A stress plateau appears at ∼−4.8 MPa, followed by a rehardening state. The deformation mode of bulk Ag2S at the initial stage is likely attributable to the migration of silver ions, and as strain increases, it is closer to that of room temperature, leading to rehardening.