Metal Halide Perovskite Nanocrystals: Synthesis, Post-Synthesis Modifications and Their Optical Properties

TL;DR

This review summarizes recent advances in the colloidal synthesis, post-synthesis modifications, and optical properties of metal halide perovskite nanocrystals, highlighting their potential in optoelectronic applications.

Contribution

It provides an updated survey of synthesis methods, post-synthesis transformations, and optical phenomena of halide perovskite nanocrystals, emphasizing defect-tolerance and quantum effects.

Findings

Control of shape, size, and optical properties via colloidal synthesis

Observation of quantum confinement and exciton binding energies

Emergence of non-linear optical phenomena like multiphoton absorption

Abstract

Metal halide perovskites represent a flourishing area of research, driven by both their potential application in photo-voltaics and optoelectronics, and for the fundamental science underpinning their unique optoelectronic properties. The advent of colloidal methods for the synthesis of halide perovskite nanocrystals has brought to the attention inter-esting aspects of this new type of materials, above all their defect-tolerance. This review aims to provide an updated survey of this fast-moving field, with a main focus on their colloidal synthesis. We examine the chemistry and the ca-pability of different colloidal synthetic routes to control the shape, size and optical properties of the resulting nano-crystals. We also provide an up to date overview of their post-synthesis transformations, and summarize the various so-lution processes aimed at fabricating halide perovskite-based nanocomposites. We then review the fundamental optical properties of halide perovskite nanocrystals, by focusing on their linear optical properties, on the effects of quantum confinement and, then, on the current knowledge of their exciton binding energies. We also discuss the emergence of non-linear phenomena such as multiphoton absorption, biexcitons and carrier multiplication. At last, we provide an outlook in the field, with the most cogent open questions and possible future directions.