Self-augmented ion blocking of sandwiched 2D/1D/2D electrode for solution processed high efficiency semitransparent perovskite solar cell

Perovskite solar cells (PSCs) have been emerged as a promising candidate for solution processable semitransparent (ST) and flexible photovoltaics. However, solution processing compatible transparent electrodes (TEs) still exist as one of the major obstacles for high efficiency and stable ST-PSCs. In this work, we constructed a sandwiched top transparent electrode by using solution processable one- and two-dimensional materials. The assembled 2D graphene with controlled reduction and 1D silver nanowires (AgNWs) electrode present significant contribution to carrier's collection and stability of devices. A self-augmented iodine ion blocking is observed, which mitigated the corrosion of TE from water, oxygen, iodine and etc.. The stability of unencapsulated ST-PSC devices has been significantly enhanced with >80% original power conversion efficiency maintained after 320 h discontinuous tests in the ambient atmosphere, comparing to <10% for AgNWs-along devices. A high-performance single junction ST-PSC was obtained with the efficiency reached up to 14.69% with the transmittance over 20% for visible light and 59% for near infrared ray. Thus, with the development of the printing compatible top 2D/1D/2D TE, the performance of all-solution processed ST-PSCs could be further enhanced and possibly applied for low-cost building integrated photovoltaics, tandem and portable electronic devices.