Chemically Inert Atomic Passivation Shell for Stable Semiconductor Nanocrystals

Abstract

The 2023 Nobel Prize in Chemistry has recognized the important discovery and development of QDs. Colloidal semiconductor nanocrystals (NCs), known as quantum dots (QDs), have attracted increased attention for a wide range of potential applications, such as displays, lighting, photovoltaics, and biological imaging, because of their high quality and size-dependent optical properties. To obtain high-quality semiconductor NCs with reduced surface defects and boosted photoluminescence emission, semiconductor shell-based surface engineering is a commonly used strategy. However, the terminated semiconductor surface is likely not immune to photodegradation or chemical degradation behavior. Insulating matrix encapsulation was demonstrated to be an alternative way to resolve the stability issue, but the bulk and insulating feature of the matrix could restrain the electrical activity and solution processability for device applications of NCs. As a compromise, the chemically inert atomic passivation shell (CIAPS) could be the ideal approach to break the above-mentioned trade-off and promote practical optoelectronic applications. The CIAPS on semiconductor NCs can protect the NCs from the surrounding environment physically and isolate photogenerated excitons from the external photochemical reactions while maintaining access to charge injection or transport for device applications.