Electric hysteresis loop solar container efficiency calculation

In this work, the dependency of the polarization (P) - electric field (E) loop area A of lead free ferroelectrics Na0.5Bi0.5TiO3 (NBT), K0.5Bi0.5TiO3 (KBT), and Na0.25K0.25Bi0.5TiO3 (NKBT) on the amplitude (E0). Do crystalline silicon photovoltaic modules have a hysteresis effect in current-voltage measurements?YouTube [pdf]
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