Hot-Carrier Injection Antennas with Hemispherical AgO<i>_x</i>@Ag Architecture for Boosting the Efficiency of Perovskite Solar Cells

Abstract

In the past few years, the power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) have increased from 3.81 to 25.2%, surpassing those of all almost all thin films solar cells. For high-performance PSCs, it is pivotal to finely regulate the charge dynamics and light management between perovskite and charge-transfer materials to balance the trade-off between optical and electrical properties. In this study, a hemispherical core-shell silver oxide (AgO<i>_x</i>) @ silver nanoparticles (Ag NPs) were grown onto the surface of the mesoporous titanium dioxide (m-TiO₂) electron-transport layer (ETL) to improve the photogenerated charge transfer without sacrificing the stability of the devices. The results show that the electrical properties of m-TiO₂ have been enhanced owing to the injection of a hot carrier in Ag NPs into the m-TiO₂ ETL filling the trap states of m-TiO₂. However, AgO<i>_x</i> on the Ag NP surfaces can isolate the touch between Ag NPs and perovskite, thereby prohibiting the perovskite decomposition. Compared with the control device, the PCE was increased from 17.87 to 20.33% for the device with HOAPs. In the meantime, the long-term stability of the PSCs is not sacrificed, which is pivotal for fabricating PSCs and optoelectronic devices.