A review on ferroelectric systems for next generation photovoltaic applications

Abstract Ferroelectric (FE) materials, which are non-centrosymmetric crystal systems with switchable polarization characterization, are known to show multifunctional application potential in various fields. Among them, the FE photovoltaic (PV) phenomenon, which has been known for several decades, is finding renewed interest recently due to its anomalous PV characteristics along with the reported efficiency exceeding the Shockley–Queisser limit in the nanoscale region. Importantly, the mechanism involved in the FE–PV effect is particularly different from the conventional PV effect exhibited by the semiconductor p–n junction solar cell. The observed above bandgap photovoltage in the FE system, and the versatility in their tunable physical characteristics makes them as one of the next generation PV materials both in terms of fundamental and technological research. However, the biggest barrier in developing the FE–PV solar cells is their very low photocurrent response, which could be surmounted by bandgap engineering, surface charge manipulation, interface control, electrode effect etc. Interestingly, the PV response coupled with other physical phenomena such as piezoelectric and flexoelectric effect gives additional momentum to the continuing research on FE–PV effect. In this article, the detailed understanding associated with various proposed mechanisms, recent progress on the improvement in FE–PV parameters, PV phenomenon coupling with other fascinating effects exhibited by FE systems are described from the fundamental to application point of view.