More effective and resilient materials for solar cells are essential for a successful green transition. Halide perovskites are emerging as a promising substitute for traditional silicon materials. Researchers from Chalmers University of Technology, located in Sweden, have uncovered new insights into the functionality of perovskite materials, marking a significant advancement in the field.
Effective and resilient materials for solar cells are crucial in the transition to a greener future. Halide perovskites are being recognized as a viable alternative to conventional silicon materials. A research team at Chalmers University of Technology in Sweden has made new discoveries about how perovskite materials operate, which represents a major leap forward.
Halide perovskites refer to a collection of materials that show significant promise and cost-effectiveness for flexible and lightweight solar cells as well as diverse optical uses like LED lighting. Their effectiveness stems from their unique ability to absorb and emit light efficiently. Nonetheless, one of the challenges is the rapid degradation of these materials. To optimize their application, it’s essential to understand the reasons behind this degradation and the underlying mechanisms of the material.
Utilizing computer simulations and machine learning
Within the group of perovskites, both 3D and 2D materials are included, with the latter often showing greater stability. A research team from the Department of Physics at Chalmers University of Technology utilized sophisticated computer simulations and machine learning techniques to investigate a variety of 2D perovskite materials, yielding key insights into their properties. This research is detailed in an article published in ACS Energy Letters.
“By mapping the materials through computer simulations and exposing them to various scenarios, we can draw conclusions regarding how the atoms react to factors like heat and light. In other words, we now possess a microscopic understanding of the material that is independent from experimental observations, yet it aligns with the same behaviors noted in experiments. Unlike traditional experiments, simulations allow us to observe in detail what leads to the measured outcomes. This enhances our understanding of how 2D perovskites function,” explains Professor Paul Erhart, a member of the research team at Chalmers University of Technology.
Exploring larger systems over extended timeframes
Employing machine learning has been pivotal for the researchers, enabling them to study larger systems over longer durations than previously feasible with conventional methodologies used just a few years ago.
“This approach has granted us a wider perspective than before while allowing us to examine materials with much greater intricacy. We’ve observed that in these ultra-thin material layers, each layer behaves uniquely, which is extremely challenging to identify experimentally,” states Associate Professor Julia Wiktor, part of the research team along with researcher Erik Fransson.
Enhanced understanding of material composition
2D perovskite materials are composed of stacked inorganic layers, interspersed with organic molecules. Understanding the specific mechanisms affecting the interaction between these layers and the organic molecules is vital for creating efficient and stable optoelectronic devices using perovskite materials.
“In 2D perovskites, you have perovskite layers interconnected by organic molecules. Our findings reveal that we can directly influence how atoms move in the surface layers through the selection of organic linkers, subsequently affecting atomic movements deeper within the perovskite layers. This movement is essential for the optical properties, resembling a domino effect,” Paul Erhart elaborates.
The findings from this research bring greater clarity regarding how 2D perovskite materials can be effectively utilized to design devices for various applications and under different temperature conditions.
“This truly allows us to comprehend the sources of stability within 2D perovskite materials, enabling us to potentially predict which linkers and configurations can enhance the material’s stability and efficiency concurrently. Our next objective is to delve into even more intricate systems, particularly focusing on interfaces critical for device functionality,” concludes Julia Wiktor.
