Abstract: The structural phase transitions and ferroelectric dynamics of lead-free AgNbO3 have attracted consid-erable attention owing to their potential in energy-storage device applications. Here, we examine the impact of Li+ doping on the phase transitions and polarization behavior of (Ag1-x Lix )NbO3 ( x = 0-7 %) ceramics through comprehensive dielectric and ferroelectric analyses. Rietveld refinement reveals a Li+ -induced phase transition from Pbcm to R 3 c , with x = 5 % and x = 6 % compositions near the morphotropic phase boundary (MPB). Dielectric anomalies identify key characteristic temperatures, supporting the con-struction of a low-field phase diagram. High-field studies uncover a direct relationship between phase structure and polarization behavior, culminating in a high-field phase diagram. Near-MPB compositions exhibit distinct structural states, elucidating the mechanisms of reversible and irreversible phase transi-tions. This work provides a comprehensive explanation of the evolution of hysteresis loop profiles, cap-turing their progression from double hysteresis loops to square loops and their subsequent reversion to double loops under varying electric field and temperature conditions. These temperature-composition ( T -x ) and temperature-electric field ( T -E ) phase diagrams provide a robust framework for understanding phase evolution, offering critical insights into optimizing AgNbO3 -based ceramics for advanced functional applications.

Key words: AgNbO₃, Lead-free, Silver niobate, Antiferroelectric, Phase translation, Ceramics