① American scientists have successfully solved the bottleneck of two-dimensional halide perovskite synthesis by controlling dynamic crystallization; ② It can help improve stability and reduce the cost of emerging technologies (such as optoelectronics and photovoltaics) based on halide perovskite; ③ The researchers said, “This research breakthrough is critical to the synthesis of two-dimensional perovskite, and it is the key to progress in solar cells and many other optoelectronic devices.”
Financial News Agency, December 13 (Editor Huang Junzhi) As we all know, with the use of light capture materials such as halide perovskite, the efficiency of solar cells is improving markedly. However, continuing to produce these materials on a large scale remains a complex task.
Recently, a group of researchers at Rice University in the US made a breakthrough in this area. They successfully solved the bottleneck in two-dimensional halide perovskite synthesis by controlling dynamic crystallization. The latest research results have recently been published in the journal “Natural Synthesis”.
This is a new process that can produce a two-dimensional perovskite-based semiconductor layer of ideal thickness and purity by controlling the temperature and duration of the crystallization process. This process, known as kinetic energy control space constraints, can help improve stability and reduce the cost of emerging halide-based perovskite technologies such as optoelectronics and photovoltaics.
The researchers said, “Producing two-dimensional perovskite crystals, layer thickness, or quantum trap thickness, also known as the 'n value', is a major bottleneck.” It is reported that an n value above 4 means that the material has a narrower band gap and higher conductivity — this is a key factor in electronic device applications.
When atoms or molecules form crystals, they arrange themselves into a highly ordered, regular lattice. Ice, for example, has 18 possible atomic arrangements or phases. Like hydrogen atoms and oxygen atoms in ice, the particles that make up the halide perovskite can also form various lattice arrangements.
The scientists' goal is to synthesize a two-dimensional halide perovskite layer, showing only a single phase throughout the process. However, the problem is that traditional high-n-value two-dimensional perovskite synthesis methods produce uneven crystal growth, which affects the performance reliability of the material.
“In traditional two-dimensional perovskite synthesis methods, due to lack of control over crystallization kinetics, you get mixed-phase crystals, which are basically a dynamic interaction between temperature and time,” the researchers said. “We designed a method to slow down crystallization and gradually adjust each kinetic parameter to achieve the best point of synthesis.”
Researchers say this work pushes the boundaries of high-quantum trap two-dimensional perovskite synthesis, making them a viable and stable choice for various applications.
They said, “We have developed a new method to improve the purity of crystals and solved a long-standing problem in this field, namely how to approach the synthesis of high-n-value, phase pure crystals.”
“This research breakthrough is critical to the synthesis of two-dimensional perovskite, which is the key to advancing solar cells and many other optoelectronic devices.” they added.