Protein-Mediated Aqueous Synthesis of Stable Methylammonium Lead Bromide Perovskite Nanocrystals: Implications for Biological and Environmental Applications

Abstract

Lead halide perovskites (HPs) hold great potential for the next generation of optoelectronic devices. However, their promise for real-world applications has not been realized because of their poor phase stability and decomposition when subjected to heat, moisture, and light. Here, we report a facile strategy for synthesizing highly stable, compositionally rich, and size-controlled methylammonium lead HP [CH3NH3PbX3 (X = Cl, Br, and I)] nanocrystals (HPNCs) in an aqueous environment, assisted by diverse proteins as capping agents. Freeing HPNC production of the complications of organic solvents provides much needed flexibility for the further cost-effective and efficient development of these structures. Stabilized by a delicate ionic balance during synthesis and via interactions with proteins, the synthesized protein-HPNCs exhibit high aqueous and colloidal stability over months. Protein capping also yields promising optical characteristics, including narrow emission wavelength and a photoluminescence quantum yield of up to ∼50%. Furthermore, we demonstrate that this approach can be extended to the synthesis of protein-mediated HPNCs with different chemistries and protein compositions. We anticipate that this method can serve as a general platform that can be used for the fabrication of a wide range of metal HPs for many biological and environmental applications including cell imaging and sensing.

Biomolecules incorporated in halide perovskite nanocrystals: synthesis, optical properties, and applications

“…5b). 96 We experimented with different proteins during the synthesis process, including casein, BSA, hemoglobin, trypsin, lysozyme, and pepsin, to demonstrate the versatility of our approach. Overall, casein-passivated HPNCs showed the highest PL intensity (Fig.…”

“…In this regard, we believe that several characteristics of the protein molecules can directly impact the quality of the NCs, including but not limited to the 3D structure, AA sequence and composition, size, degree of hydrophobicity and isoelectric point. 96 Given the complex nature of proteins and the inter-related nature of these parameters, further studies are needed to elucidate the precise roles of each of the above-mentioned parameters on the optoelectronic properties of HPNCs.…”

“…The complex nature of these macromolecules makes it possible to rationally design protein-inorganic material interactions and direct the synthesis of complex hierarchical structures which are not easily attainable by traditional techniques. Various new nanostructures generated through protein-inorganic material 96 (f ) The impact of casein, BSA, hemoglobin, trypsin, lysozyme, and pepsin proteins on the PL spectra of HPNCs synthesized with constant protein molar ratio. 96 (g) PL emission spectra of the encapsulated CsPbBr 3 NCs as a function of SHβ-CD concentration.…”

“…Various new nanostructures generated through protein-inorganic material 96 (f ) The impact of casein, BSA, hemoglobin, trypsin, lysozyme, and pepsin proteins on the PL spectra of HPNCs synthesized with constant protein molar ratio. 96 (g) PL emission spectra of the encapsulated CsPbBr 3 NCs as a function of SHβ-CD concentration. 98 (h) TEM image and schematic of MAPbBr 3 /β-CD NCs achieved through host-guest interactions between β-CD and hexylamine, photograph of LED fabricated using these HPNCs.…”

“…96 (d) PL emission (λ ex = 405 nm) of BSA-HPNCs as a function of protein concentration. The inset exhibits the PL peak intensities along with PLQY variations with the amount of BSA protein 96. (e) Impact of pH of the synthesis solution on PL emission of BSA-HPNCs.…”