Perovskite minerals are a class of materials that share a specific crystal structure originally discovered in the mineral calcium titanium oxide (CaTiO₃). Solar cells made from these minerals are considered the future of solar energy, providing similar efficiency to silicon-based cells, while being potentially easier and cheaper to manufacture. Moreover, perovskite cells are more flexible, meaning they can be applied to building materials. As such, Analysts predict the perovskite solar cell market will grow rapidly, with an expected market value of over $6 billion by 2030.
A recent study by solar engineers from the Huaqiao University, who worked together with chemists from the City University of Hong Kong might further popularize perovskite cells. According to the researchers, they achieved 26.39% efficiency with an aperture area of 0.12 cm2, which is impressive for a perovskite cell. However, other advancements seem even more impressive. For instance, the cells retained 95.4% of their initial efficiency after 1,100 hours of use in maximum power point tracking. Perovskite cells usually suffer from degradation, and this design could make them significantly more durable.
To achieve those figures, the team created an ultra-thin (~7 nm) p-type polymeric interlayer, which has strong ion-blocking properties. The hole-selective interlayer was created using a spin coating of PDTBT2T-FTBDT (D18), sitting between the perovskite and hole transport layer. In the context of solar cells, “holes” refer to the absence of an electron in a material’s atomic structure. They are not physical holes but are conceptualized as positive charge carriers that play a crucial role in the movement of electric current.
“The idea of incorporating a hole-selective interlayer in PSCs was inspired by proton exchange membrane (PEM) fuel cells, where the PEM serves as a proton conductor while blocking the diffusion of other chemical species. To achieve highly stable n-i-p PSCs with high efficiency, the inserted hole-selective interlayer is expected to efficiently transport photo-generated holes and inhibit ion diffusion,” said researchers in the study published in the Nature Communications journal.
Article & Image source Nature communications
