I-002

Artiom Magomedov

artiom.magomedov@ktu.lt

Kaunas University of Technology, Lithuania

Molecular Innovations for Tandem Solar Cells: The Impact of 2PACz and Related Materials

The quest for higher efficiency in solar energy conversion is a continuous challenge. While silicon (Si) solar cells are dominating the market, their efficiency is fundamentally constrained by the Shockley-Queisser limit, making it impossible to reach 30% power conversion efficiency (PCE). To overcome this barrier, novel approaches such as tandem solar cells have been developed, where a wide-bandgap perovskite top cell is combined with a silicon bottom cell to better utilize the solar spectrum.

Although perovskite-Si tandem devices offer an excellent spectral match, their success depends not only on absorber optimization but also on interfacial engineering. Charge-selective layers play a crucial role in reducing recombination losses, enhancing carrier extraction, and potentially ensuring long-term stability.

In this presentation, I will discuss how the development of 2PACz and its related materials has been instrumental in surpassing 30% PCE in tandem solar cells. The idea of the utilization of the strong binding of the phosphonic acid anchoring group to the ITO surface, in combination with carbazole chromophore, proved to be a versatile and robust solution. I will outline the molecular design strategies behind these self-assembled monolayers and their influence on device performance. Finally, I will discuss the remaining scientific challenges in understanding and development of such materials.