Publication date: 28th August 2024
Lead halide perovskite nanocrystals (LHP NCs) are an emerging class of light-emitting semiconductors owing to their remarkable optoelectronic properties such as their high photoluminescence quantum yield (PLQY), tunable emission across the visible spectrum emission, and facile synthesis, which make them excellent candidates in high-performance devices such as LED lights and photovoltaic devices. One of the most interesting features of halide perovskites in comparison to classical semiconductor materials is their high defect tolerance, I.e., the uncoordinated ions and surface dangling bonds results can only form states within or close to valance or conduction bands. However, chlorine-based perovskites possess low defect tolerance and thus the surface defects result in the formation of deep traps that significantly reduce their photoluminescence quantum yield (PLQY).1 Consequently, the PLQY of as-synthesized Cl-perovskite NCs is much lower (1-5%) than Br or I-perovskite NCs (80-100%).
In this work, I will discuss a comprehensive study of post-synthetic surface passivation of CsPbCl3 NCs with metal halides and molecular ligands to improve the PLQY of NCs. A large variety of ligands with different functional groups such as quaternary amines, sulfonates, and phosphonates were screened to study the enhancement of PLQY according to their binding ability to the NC surface. In addition, different metal halides are screened to fill surface vacancies and thus improve the PLQY. These studies revealed that the chloride vacancies are the main reason for the low PLQY of Cl-perovskite NCs. Furthermore, we demonstrated the direct synthesis of CsPbCl3 NCs with relatively high PLQY using the strongly binding ligands obtained from the screening of post-synthetic ligand passivation. Our results not only provide an in-depth understanding of the type of trap states in CsPbCl3 NCs but also unravel the ligand types for effective passivation of CsPbCl3 NCs, thus offering a new avenue to synthesize high-quality luminescent NCs either by direct synthesis or post-synthetic passivation.
L.P. Acknowledge the support from the Spanish Ministerio de Ciencia e Innovación through Ramón y Cajal grant (RYC2018-026103-I) and the start-up grant from the Xunta de Galicia. R. L.Z. H. acknowledges support from the Royal Academy of Engineering (No.: RF\201718\1701).
nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.
Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.
International Conference on Hybrid and Organic Photovoltaics
International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.
Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics
The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.
The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.