From fundamental properties of multidimensional halide perovskites to energy conversion applications

Abstract

Perovskite-based semiconducting systems have been widely discussed as the holy grail of new technologies with outstanding potential for optoelectronic and energy conversion applications. Besides being synthesized through solution-processed method, adjustable band gaps, low exciton binding energy, very large optical absorption coefficients across the visible solar spectrum, long hole-electron diffusion length leading to efficient charge separation/collection, and high defect tolerance are important physical properties observed for these materials. The versatility for photoconversion and emission is intimately related to structural connectivity and dimensionality resulting in improved properties and even new functionalities. From dimensional manipulation, there is a scalable electronic arrangement towards to the balance in between efficiency and stability. The well-established ABX3 3D perovskite faces challenges mostly associated to the interfacial degradation under light and moisture conditions due to the ionic transport. On the other hand, layered perovskites with [MX6]4- octahedra spaced by organic molecule forming 2D Ruddlesden-Popper family have demonstrated peculiar optoelectronic properties with tunable band gap. The quantum well configuration exhibits a hydrophilicity and impairs ionic conductivity preventing degradation differently from its 3D counterpart. Furthermore, the electronic transport anisotropy makes these materials extremely interesting for applications in electronic devices. Another perspective is the electronically arranged 0D perovskites, which has shown high quantum yield, exciton binding energy and stability associated to their no networked octahedra, being classified as excellent candidates for photo-emission/detectors devices. In this context, the scope of this proposal raises on addressing the fundamental halide perovskites properties through dimensionality and electronic defects manipulation providing a single host material working synergistically with complementary properties conferred by quantum confinement. In view of the dimensionality, it is expected to build efficient systems controlling stability and band gap for emitting devices (2D perovskite), high quantum yield (0D structures), improving electronic transport properties in conversion devices (3D-1D structures), which might enable to overcome challenges in the research field. Furthermore, this proposal has a wide collaborations network endorsing the completeness of the proposed study. Finally, it is intended to gather a vast knowledge of these perovskites, as well as acquire prototypes linking theoretical, experimental and applied science efforts in order to outline better employed structure regarding the device efficiency. (AU)