Sputtered SnO₂ as an interlayer for efficient semitransparent perovskite solar cells

Abstract

SnO2 is widely used as the electron transport layer (ETL) in perovskite solar cells (PSCs) due to its excellent electron mobility, low processing temperature, and low cost. And the most common way of preparing the SnO2 ETL is spin-coating using the corresponding colloid solution. However, the spin-coated SnO2 layer is sometimes not so compact and contains pinholes, weakening the hole blocking capability. Here, a SnO2 thin film prepared through magnetron-sputtering was inserted between ITO and the spin-coated SnO2 to act as an interlayer. This strategy can combine the advantages of efficient electron extraction and hole blocking due to the high compactness of the sputtered film and the excellent electronic property of the spin-coated SnO2. Therefore, the recombination of photo-generated carriers at the interface is significantly reduced. As a result, the semitransparent perovskite solar cells (with a bandgap of 1.73 eV) based on this double-layered SnO2 demonstrate a maximum efficiency of 17.70% (stabilized at 17.04%) with negligible hysteresis. Moreover, the shelf stability of the device is also significantly improved, maintaining 95% of the initial efficiency after 800-hours of aging.

TiO2/SnO2 electron transport double layers with ultrathin SnO2 for efficient planar perovskite solar cells

“…The redox reaction is further suppressed by the ultrathin SnO 2 coating, indicating that the ultrathin ALD SnO 2 layer is compact and fills the pinholes in the TiO 2 ETL. [42] Herein, a TiO 2 /SnO 2 double ETL with an ultrathin but compact SnO 2 layer was successfully constructed using ALD process.…”

Br Addition Combined with Non-Preheating Method to Prepare Semitransparent Quasi-2D Perovskite Solar Cells with High Average Visible Light Transmittance

“…Increasing the bandgap of perovskite is conducive to improving AVT, − because it allows light to pass below the bandgap energy and reduces the average light absorption across the visible spectrum. At the same time, a wider bandgap for ST-PSCs will get a higher open-circuit voltage ( V oc ), , which is beneficial to their efficiency.…”