Publication date: 28th August 2024
Metal halide perovskite nanocrystals (NCs) have emerged as a promising material for various applications due to their unique optoelectronic properties. Traditional fabrication methods for these NCs rely on colloidal chemistry, which can be time-consuming and may require complex purification steps. In this presentation, we will discuss the use of ultrafast laser processing as a versatile tool for the controlled modification of metal halide perovskite NCs. This technique offers several advantages, including rapid processing times, control over NC morphology, and the ability to conjugate NCs with 2D materials.
We will present our work on the laser-induced morphological and structural changes of cesium lead bromide nanocrystals. By varying the laser fluence and wavelength, we have achieved different transformations in these NCs, including exfoliation, fragmentation, and oriented attachment leading to the formation of nanoplatelets and nanosheets. These transformations are accompanied by partial or complete anion exchange, which can be controlled by the choice of solvent.
Furthermore, we will discuss our findings on the laser-assisted fabrication of metal halide perovskite-2D nanoconjugates. By irradiating a solution containing both perovskite NCs and graphene-based materials with femtosecond laser pulses, we have successfully decorated the 2D flakes with perovskite NCs without affecting their primary morphology. The density of anchored NCs can be finely tuned by adjusting the number of irradiation pulses, allowing for precise control over the properties of the resulting nanoconjugates.
Finally, we will present our latest research on the application of laser-processed perovskite-rGO conjugates as electrodes in Zn-ion capacitors. The laser-induced conjugation method enables the uniform distribution of perovskite NCs on reduced graphene oxide (rGO) sheets, resulting in enhanced electrochemical performance. The resulting electrodes exhibit high specific capacitance and excellent stability, demonstrating the potential of this approach for energy storage applications.
Overall, our work highlights the versatility of ultrafast laser processing as a powerful tool for the controlled synthesis and modification of metal halide perovskite nanocrystals. This technique offers a rapid and efficient route to fabricate perovskite-2D nanoconjugates with tailored properties, opening up new possibilities for their application in various fields, including optoelectronics, energy conversion, and energy storage.
This research project has received funding from the EU's Horizon Europe framework programme for research and innovation under grant agreement BRIDGE (n. 101079421)