Fluorene- and fluorenone-based molecules as electron-transporting SAMs for photovoltaic devices.

New semiconductors containing fluorene or fluorenone central fragments along with phosphonic acid anchoring groups were synthesized and investigated as electron transporting materials for possible application in photovoltaic devices. These derivatives demonstrate good thermal stability and suitable electrochemical properties for effective electron transport from perovskite, SbS and SbSe absorber layers. Self-assembled fluorene and fluorenone electron-transporting materials have shown improved substrate wettability, indicating bond formation between monolayer-forming compounds and the ITO, TiO, SbS, or SbSe surface.

Energy-Level Interpretation of Carbazole Derivatives in Self-Assembling Monolayer.

Energy-level alignment is a crucial factor in the performance of thin-film devices, such as organic light-emitting diodes and photovoltaics. One way to adjust these energy levels is through chemical modification of the molecules involved. However, this approach may lead to unintended changes in the optical and/or electrical properties of the compound.