Ternary hybrid systems of P3HT-CdSe-WS₂ nanotubes for photovoltaic applications

Hybrid heterojunctions of conjugated polymers and inorganic nanomaterials are a promising combination for obtaining high performance solar cells (SC). In this work we have explored new possible uses of the WS2 nanotubes (NTs) both as the only acceptor material blended with a polymer and in ternary systems mixed with a polymer and quantum dots (QDs). In particular we have spectroscopically investigated binary blends of poly(3-hexylthiophene) (P3HT) and WS2 NTs, P3HT and CdSe QDs, and ternary blends of P3HT, CdSe QDs and WS2 NTs. We report fluorescence quenching effects of the QD signal in the P3HT-CdSe-WS2 system with the increase of NT concentration. Static and time-resolved fluorescence studies reveal efficient resonant energy transfer from the QDs to the NTs upon photoexcitation. The evidence of energetic interaction between WS2 NTs and QDs opens new fields of application of WS2 NTs and holds very promising potential for improving charge transfer phenomena in the active layer of hybrid solar cells.