Enhanced charge extraction in textured perovskite-silicon tandem solar cells via molecular contact functionalization

Huang J., Zhang L., Yilmaz C., Qu G., Zemer I., Hooijer R., ...Daha Fazla

Joule, 2025 (SCI-Expanded, Scopus) identifier

  • Yayın Türü: Makale / Tam Makale
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1016/j.joule.2025.102227
  • Dergi Adı: Joule
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, Geobase, INSPEC
  • Anahtar Kelimeler: bromine substitution, conjugated linker, perovskite-silicon tandem solar cells, self-assembled molecules
  • Marmara Üniversitesi Adresli: Evet

Özet

High-efficiency perovskite-silicon tandem solar cells require effective charge recombination at the interconnecting junction. On textured silicon bottom cells, conventional alkyl-chain-based self-assembled molecules (SAMs) tend to aggregate, limiting device performance. To overcome this, we synthesized a conjugated linker SAM, (4-(7 H -dibenzo[ c , g ]carbazol-7-yl)phenyl)phosphonic acid (Bz-Ph p PACz), enabling efficient charge transport. Our molecular design included controlling bromine (Br) impurities in the SAM precursors, as chemical analysis revealed that commercial 4PADCB contains trace bromine species that passivate interface defects. We optimized the molecular mixture by precisely blending brominated and non-brominated counterparts. The conjugated framework promotes charge transport on rough surfaces, while bromine improves energy alignment, passivates defects, and relieves lattice strain in the perovskite layer. This approach yielded perovskite-silicon tandem cells on Czochralski (CZ) silicon with 31.4% efficiency, highlighting the critical role of molecular design and impurity control in achieving high-performance tandem devices.