Oxygen management in carbon electrode for high-performance printable perovskite solar cells

Full-printable all-inorganic mesoporous network has emerged as a promising device scaffold for perovskite photovoltaic applications because of its highly stable device architecture and essentially scalable fabrication process, but practical application of this photovoltaic technology requires further advancement on power conversion efficiency. Here we introduce a facile oxygen management strategy in the carbon electrode (CE) to simultaneously tune energy alignment and the interface contact between perovskite and the CE. Augmenting the oxygen content of carbon black in CE not only elevates the energy level of the CE, but also optimizes the perovskite/CE interface contact, leading to a significantly enhanced hole extraction efficiency at the interface of perovskite/CE. These enable us to fabricate solar cells possessing a maximum efficiency of 15.7% benefiting from open-circuit voltage enhancement of 100 mV, which is significantly higher than that of control device (13.6%) without oxygen management in the CE. The present work diversifies a strategy to optimize the energy level alignment and interface contact of the perovskite/CE for the efficient printable mesoscopic perovskite solar cells.