Constructing High-Performance Solar Cells and Photodetectors with a Doping-Free Polythiophene Hole Transport Material

The emerging solution-based solar cells and photodetectors have gained worldwide research interest over the past decades. Hole transport materials (HTMs) have greatly advanced the progress of these solution-based electronics. Nevertheless, developing low-cost and efficient HTMs is far from satisfactory. In this contribution, poly(3-pentylthiophene) (P3PT) is introduced as a facile, low-cost, and versatile dopant-free polymer HTM for both quantum dot (QD) and perovskite electronic devices. Compared to the broadly used poly(3-hexylthiophene), P3PT presents the reduced molecular aggregation and preferential face-on orientation, which can markedly enhance the hole-carrier transport in optoelectronic devices. Accordingly, P3PT can deliver the substantial improvement of photovoltaic performance from ∼8.6% to ∼9.5% for QD/polythiophene solar cells and from ∼16% to ∼18.8% for perovskite/polythiophene solar cells, which are both among the topmost values in the corresponding fields. Furthermore, P3PT HTMs can also significantly enhance the photodetection performance of QD and perovskite photodetectors by a factor of ∼3, indicating its great application potential in a variety of emerging optoelectronics.