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 semi-transparent (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.