Near-Infrared Light Emitting Metal Halides: Materials, Mechanisms, and Applications

TL;DR

This review discusses recent advances in near-infrared light-emitting metal halides, highlighting their materials, mechanisms, and applications, with a focus on improved device efficiency and stability.

Contribution

It provides a comprehensive summary of different types of NIR-emitting metal halides and their recent progress, emphasizing mechanisms and potential applications.

Findings

NIR-emitting perovskite LEDs achieve over 20% EQE.

Device stability exceeds 10,000 hours.

Diverse metal halide materials enable tunable NIR emission.

Abstract

Near-Infrared (NIR) light emitting metal halides are emerging as a new generation of optical materials owing to their appealing features, which include low-cost synthesis, solution processability and adjustable optical properties. NIR emitting perovskite-based light-emitting diodes (LEDs) have reached an external quantum efficiency (EQE) over 20% and a device stability of over 10,000 h. Such results have sparked an interest in exploring new NIR metal halide emitters. In this review, we summarize several different types of NIR-emitting metal halides, including lead/tin bromide/iodide perovskites, lanthanide ions doped/based metal halides, double perovskites, low dimensional hybrid and Bi3+/Sb3+/Cr3+ doped metal halides, and assess their recent advancements. The characteristics and mechanisms of narrow-band or broadband NIR luminescence in all these materials are discussed in detail. We also highlight the various applications of NIR-emitting metal halides and provide an outlook for the field.