Hole-Induced Charge\nTransfer Dynamics at the CsPbBr<sub>3</sub> Perovskite Quantum Dot\nInterface

In the quest to advance solar energy conversion, understanding\nthe intricacies of charge transfer (CT) at interfaces has become crucial\nfor photovoltaic applications. Efficient CT is essential for minimizing\nenergy losses due to recombination and enhancing the efficiency of\nthe devices. Herein, we delve into the significance of the CT process\nin the improvement of current conduction across the interface by using\nseveral spectroscopic and microscopic measurements. A photoinduced\nCT mechanism in CsPbBr<sub>3</sub> perovskite quantum dots (PQDs)\nis explored with a band-aligned hole acceptor, anthracene. All of\nthe spectroscopic measurements reveal a prominent CT from PQDs to\nanthracene through hole transfer, as evinced from the energy level\ndiagram and density of states calculations. The electrical measurements\nacross an electrode-semiconductor-electrode junction using conductive\natomic force microscopy reflect an increase in the conductance in\nPQD after the introduction of anthracene. The inclusion of anthracene\nin the PQD changes the nature of the current–voltage curve\nfrom nonlinear to Ohmic one, revealing only direct tunneling and both\ndirect and Fowler–Nordheim tunneling for PQD with and without\nanthracene, respectively. These findings can contribute to the development\nof efficient and cost-effective optoelectronic devices with a careful\nselection of simple molecules as charge transport or some additional\nlayers.