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

Abstract

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.