Embedding Perovskite Nanocrystals into a Polymer Matrix for Tunable Luminescence Probes in Cell Imaging

Abstract

Lead halide perovskite nanocrystals (NCs) with bright luminescence and broad spectral tunability are good candidates as smart probes for bioimaging, but suffer from hydrolysis even when exposed to atmosphere moisture. In this paper, a strategy is demonstrated by embedding CsPbX3 (X = Cl, Br, I) NCs into microhemispheres (MHSs) of polystyrene matrix to prepare “water‐resistant” NCs@MHSs hybrids as multicolor multiplexed optical coding agents. First, a facile room‐temperature solution self‐assembly approach to highly luminescent colloidal CsPbX3 NCs is developed by injecting a stock solution of CsX⋅PbX2 in N,N‐dimethylformamide into dichloromethane. Polyvinyl pyrrolidone (PVP) is chosen as the capping ligand, which is physically adsorbed and wrapped on the surface of perovskite NCs to form a protective layer. The PVP protective layer not only leads to composition‐tunable CsPbX3 NCs with high quantum yields and narrow emission linewidths of 12–34 nm but also acts as an interfacial layer, making perovskite NCs compatible with polystyrene polymers and facilitating the next step to embed CsPbX3 NCs into polymer MHSs. CsPbX3 NCs@MHSs are demonstrated as multicolor luminescence probes in live cells with high stability and nontoxicity. Using ten intensity levels and seven‐color NCs@MHSs that show non‐overlapping spectra, it will be possible to individually tag about ten million cells.

Highly Luminescent Lead Halide Perovskite Quantum Dots in Hierarchical CaF2 Matrices with Enhanced Stability as Phosphors for White Light‐Emitting Diodes

“…[30][31][32] The crystal structure of lead halide perovskite would be easily destroyed when they are exposed in the ambient air, which leads to fluorescence quenching and then decreasing the electro-optical conversion efficiency of devices. [35][36][37][38][39][40][41] Indeed, the Lead halide perovskite quantum dots (PQDs) have been widely recognized as highly luminescent materials for efficient optoelectronic applications owing to their fascinating electronic and optical properties. [34] In general, the dense polymer chains could passivate the surface of perovskite as well as protect them from contacting with environment directly.…”

“…[39][40][41][42] However, suffering from the poor thermal stability of organic components, polymers do not seem to be the best choice to protect PQDs. Especially, the obtained perovskite-polymer composites display waterproof property whereas the pristine perovskite materials are highly sensitive to humidity.…”

Lead Halide Perovskite Nanocrystals in the Research Spotlight: Stability and Defect Tolerance

“…110 PVP acted as the capping ligand and was adsorbed onto the perovskite NC surface and in doing so formed a protective layer. The PVP surface thus formed also served as an interface layer for further addition of an additional polystyrene matrix allowing the CsPbX 3 NCs to be embedded in polymer MHSs.…”

A Two‐Dimensional Ruddlesden–Popper Perovskite Nanowire Laser Array based on Ultrafast Light‐Harvesting Quantum Wells

“…[4] Organic-inorganic halide hybrid perovskite materials are an emerging class of solution-processed semiconductors for high-efficiencyoptoelectronic devices, [5] which are promising for solar cells(SCs), [5b] light-emitting diodes (LEDs), [6] optical amplifiers, [7] and optically pumped lasers. [9] Tw o-dimensional (2D) organic-inorganic hybrid Ruddlesden-Popper perovskites (RPPs) are solution-processed quantum well (QW) materials [10] that show unique and promising advantages as compared with their 3D counterparts, [11] including both technologically relevant photo-/chemical stability and quantum tunable optoelectronic properties. [2] On the one hand, these self-assembly NWs were solution grown with random orientation by exposing al ead acetate film to as olution of MA halide salt.…”