A technique to boost the effectiveness as well as lasting security of perovskite solar cells

• Over the past couple of years, scientists have actually been attempting to create brand-new styles for perovskite solar cells that can improve their efficiency, efficiency as well as stability over time. One feasible way of achieving this is to integrate 2-D and 3-D halide perovskites in order to take advantage of the useful residential or commercial properties of these two various sorts of perovskites

The two-dimensional crystal structure of 2-D halide perovskites is highly immune to dampness; therefore, it can help to boost the performance as well as durability of solar cells with a light-absorbing 3-D halide perovskite layer. Nevertheless, the majority of the methods for incorporating 2-D as well as 3-D halide perovskites proposed thus far just entail mixing these 2 materials together (e.g., blending 2-D forerunners with a solution-based 3-D perovskite or responding 2-D precursor solutions on top of a 3-D perovskite layer).

Researchers at Seoul National University and Korea University have actually lately designed an alternative strategy for producing solar cells that combine 2-D and also 3-D halide perovskites. This approach, described in a paper published in Nature Energy, can assist to concurrently enhance both the effectiveness and also long-term security of these cells.

" Although the blending of different perovskite films has some positive effect on efficiency as well as wetness security, the 2-D development with the service process with the chemical reaction of the 2-D precursor with 3-D halide has restrictions, such as susceptability to warmth and also difficulty in applying junctions for inner electrical field layout in the tool because of an unplanned quasi-2-D stage development," Prof. Jun Hong Noh, among the scientists who performed the research study, informed TechXplore. "We have tried to address this trouble."

To get over the constraints of previously recommended methods for creating 2-D/3-D halide perovskite-based solar cells, Prof. Noh and his associates attempted to create an appropriate junction in between a solar cell's light-absorbing layer (with a slim bandgap) and also the functional 2-D layer (with a wide bandgap). This useful layer is located in many existing high-efficiency solar cell structures, including gallium arsenide (GaAs) as well as heterojunction with inherent slim layer (HIT) silicon solar cells.

GaAs and HIT solar cells utilize a III-V semiconductor (AlGaAs) and also amorphous silicon (a-Si), specifically, as a practical layer with a large bandgap, in order to develop an appropriate interior electrical field. In these solar cells, the functional layer and the light-absorbing layer are commonly homogenous. To develop their solar cells, Prof. Noh and also his associates thus made sure that they used a 2-D halide perovskite with a wide bandgap that was identical with the 3-D halide perovskite they selected.

" In order to create an intact 2-D/3-D junction, we pertained to the verdict that the option procedure need to be excluded when developing the junction," Prof. Noh said. "That is exactly how the solid-phase in-plane development (SIG) procedure was born. In the SIG process, a 3-D film and a 2-D film are individually prepared, the 2-D film is piled on top of the 3-D film to ensure that they face each other, and then heat and stress are related to induce the 2-D film to expand on the 3-D layer."

Utilizing this one-of-a-kind design strategy, the researchers were able to expand a highly crystalline 2-D film in addition to the 3-D halide perovskite film without damaging it and also without using solvents. This led to the development of an intact 2-D/3-D junction.

Prof. Noh and his colleagues discovered that their approach does not result in the unintentional formation of a quasi-2-D film, which can in some cases take place when 2-D and 3-D halide perovskite films are blended with each other. The resulting framework is thermally steady, while likewise permitting the scientists to conveniently regulate the thickness of the 2-D film as well as adjust the 2-D/3-D junction's interior electric area.

" Our approach can all at once boost performance and lasting stability of perovskite solar cells," Prof. Noh stated. "In addition, we presented an approach to make the intact junction (halide/halide) between homogeneous halides, as opposed to the junction in between heterogeneous products (i.e., halide/oxides or halide/organics), which is the standard gadget framework until now in perovskite solar cells."

The design approach introduced by Prof. Noh and also his colleagues could quickly be utilized to create 2-D/3-D halide junction perovskite solar cells that have both a high effectiveness and also a high thermal security. In the future, their job could additionally motivate various other research teams to employ the exact same approach or create similar approaches to improve the efficiency of perovskite-based solar cells.

" In this recent study, we utilized butylammonium lead iodide (BA2PbI4), the simplest framework among 2-D halide perovskites," Prof. Noh stated. "However, research study exploring the application of new 2-D perovskites is underway for a far better 2-D/3-D junction layout. With this, we wish that we will certainly have the ability to implement a high-efficiency perovskite solar cell, such as GaAs."