카이랄 전이현상을 기반으로 한 신조성 카이랄 페로브스카이트 소재 설계 및 차세대 에너지 변환 소자 응용 동향

Chiral Perovskite Materials Design and Energy Conversion Applications Based on Chirality Transfer Phenomena: A Review

For the last few decades, Hybrid organic-inorganic perovskites (HOIPs) have been extensively studied as a prototypical material for various energy conversion device applications, including photovoltaic solar cells, photodetectors, light emitting diodes. By virtue of their excellent optical and electrical properties, such as high absorption coefficient, exceptionally long carrier lifetime, and high defect tolerance, HOIPs-based energy conversion devices exhibited unprecedented device performance. Since the unique chiroptical properties of HOIPs were first examined in 2017, HOIPs have been rediscovered as a new-type of chiral semiconductor for next-generation (next-G) energy conversion devices. These new-type of perovskite, chiral HOIPs, which consist of two building blocks (i.e., chiral organic molecules and achiral inorganic frameworks), spontaneously adopt multi-quantum well layered structure. Interestingly, owing to the chirality transfer phenomena, the chirality of organic molecules can be effectively imposed on an inorganic framework, resulting in differential optical response to light depending on the polarization state of light, even in the visible light region. Recently, it has been demonstrated that chirality transfer phenomena can also endow chiral HOIPs with spin-filtering behavior, where chiral HOIPs allow only one of the spin states to pass through while blocking the other spin state. This review paper examines the relationship between the degree of chirality transfer and optical/electrical properties based on different chirality transfer mechanisms. Promising strategies to improve the chiroptical and spin-related properties of chiral HOIPs are discussed, including chiral cation substitution and halide anion composition engineering to amplify asymmetric hydrogen interaction and chiral distortion. This paper also covers various energy conversion devices based on chiral HOIPs. Finally, the review highlights the further research direction on next-G energy conversion devices, especially in spin-optoelectronics and spin-dependent energy conversion processes, to fully exploit the potential of chiral HOIPs for efficient and sustainable energy conversion technologies.