Researchers have discovered a technique that allows them to engineer a specific class of materials called layered hybrid perovskites (LHPs) down to the atomic level. This process enables precise control over how these materials convert electrical charge into light, making them ideal for use in next-generation printed LEDs and lasers. The method also shows promise for engineering other materials for use in photovoltaic devices. Perovskites are known for their desirable optical, electronic, and quantum properties and consist of thin sheets of semiconductor material separated by organic spacer layers. By engineering these materials, researchers can optimize their performance characteristics for various applications.
In the past, there was limited understanding of how to effectively engineer LHPs to control their performance characteristics. The discovery sheds light on the formation of quantum wells in LHPs which are sheets of semiconductor material sandwiched between spacer layers. The size distribution of these quantum wells is critical for efficiently converting energy from high-energy structures to low-energy structures at the molecular level. However, previous studies had shown a disconnect between the size distribution of quantum wells observed via X-ray diffraction and optical spectroscopy. This inconsistency led researchers to investigate the role of nanoplatelets in the formation of layered materials in LHPs and how they impact the size and distribution of quantum wells.
Through a series of experiments, researchers found that nanoplatelets play a key role in determining the size and distribution of quantum wells in LHP films. These individual sheets of perovskite material act as templates for layered materials that form beneath them, creating quantum wells of specific thickness based on the nanoplatelet size. By controlling the growth of nanoplatelets, researchers were able to tune the size and distribution of quantum wells in LHP films, leading to efficient energy cascades that enhance the material’s performance in laser and LED applications. This finding also explains the discrepancies between X-ray diffraction and optical spectroscopy in detecting the size distribution of quantum wells in LHPs.
The discovery that nanoplatelets can be used to engineer the structure and properties of perovskite materials beyond LHPs opens up new possibilities for improving the performance of these materials in various applications. By manipulating nanoplatelets, researchers can enhance the structure of other perovskite materials used in solar cells and photovoltaic technologies, leading to improved photovoltaic performance and stability. This finding has broad implications for the development of next-generation materials for energy conversion and photonics applications. The research was supported by grants from the National Science Foundation and the Office of Naval Research, highlighting the significance of this work in advancing materials science and engineering.
