Synthesis of organic-inorganic perovskite and all-inorganic lead-free double perovskite nanocrystals by femtosecond laser pulses
Volodymyr Vasylkovskyi, Andrey Evlyukhin, Elena Schlein, Mykola Slipchenko, Roman Kiyan, Kestutis Kurselis, Vladimir Dyakonov, Boris Chichkov
TL;DR
This work introduces a ligand-free synthesis route for perovskite nanocrystals via femtosecond pulsed laser ablation in ambient air. It systematically compares organic–inorganic MAPbX3 and all-inorganic Cs2AgBiX6 NCs, showing preserved crystallinity and distinct size regimes (MAPbX3 ~60–107 nm; Cs2AgBiX6 ~11–16 nm) with tunable optical properties. Size-dependent blue shifts are observed for MAPbX3 (17–40 nm) due to quantum confinement, while Cs2AgBiX6 exhibits broader emission tied to its indirect band gap and defect tolerance. The method is scalable and environmentally friendly, enabling high-purity, ligand-free NCs suitable for advancing perovskite-based optoelectronic and quantum devices.
Abstract
Perovskite materials are at the forefront of modern materials science due to their exceptional structural, electronic, and optical properties. The controlled fabrication of perovskite nanostructures is crucial for enhancing their performance, stability, and scalability, directly impacting their applications in next-generation devices such as solar cells, LEDs, and sensors. Here, we present a novel, ligand-free approach to synthesize perovskite nanocrystals (NCs) with average sizes up to 100 nm, using femtosecond pulsed laser ablation (PLA) in ambient air without additional liquid media. We demonstrate this method for both organic-inorganic (methylamino lead) hybrid perovskites (MAPbX3, X = Cl, Br, I) and fully inorganic lead-free double perovskites (Cs2AgBiX6, X = Cl, Br), achieving high-purity NCs without stabilizing ligands - a critical advancement over conventional chemical synthesis methods. By tailoring laser parameters, we systematically elucidate the influence of perovskite composition (halide type, organic vs. inorganic cation, single versus double perovskite structure) on the ablation process and the resulting nanocrystal properties. Transmission electron microscopy and X-ray diffraction confirm the preservation of crystallinity, with MAPbX3 forming larger (approximately 90 nm) cubic NCs and Cs2AgBiX6 forming smaller (approximately 10 nm) rounded NCs. Photoluminescence spectroscopy reveals pronounced size-dependent blue shifts (17-40 nm) due to quantum confinement, particularly for Br and I containing perovskites. This clean, scalable, and versatile PLA approach not only provides direct access to high-purity, ligand-free perovskite NCs with tunable optical properties but also represents a significant advance in the fabrication of nanostructures, enabling the exploration of new perovskite-based optoelectronic and quantum devices.