The discovery of silver chalcogenides ductile semiconductors with high room-temperature plasticity holds significant promise for the development of bendable thermoelectric and electronic devices. However, the atomic-scale origins of their plasticity, ranging from dislocation slip to sublattice amorphization, remain diverse and material-specific. Here, we report a distinct deformation mechanism in Ag2Te through stress-driven and ionic-hop-mediated domain rotation. By in-situ scanning/transmission electron microscopy (S/TEM), we directly observe the hopping of Ag ions to adjacent vacancies stabilizes the deformed Te-sublattice and facilitates a coordinated ~92.2° lattice rotation that accommodates substantial plastic strain. This mechanism, which preserves long-range crystallinity, contrasts with both traditional dislocation-mediated plasticity and stress-induced amorphization pathways. Combined with its excellent thermoelectric performance (ZT value of ~0.67) at room temperature, Ag2Te emerges as a promising flexible electronic material.
Guo et al. (Thu,) studied this question.