Modifying Perovskite Films with Polyvinylpyrrolidone for Ambient-Air-Stable Highly Bendable Solar Cells

Abstract

One major drawback that prevents the largescale practical implementation of perovskites is their susceptibility to performance degradation in humid environments. Here, we achieved uniform, stable perovskite films within a polyvinylpyrrolidone (PVP) polymer frame via mild solution processing in ambient air with over 60% relative humidity. In addition to facilitating film formation, the hydrophobic PVP served to protect the perovskite grains from atmospheric moisture. Use of PVP, coupled with optimization of the deposition parameters, provided for compact, smooth, pinhole-free perovskite films that when incorporated into a photovoltaic device exhibited highly reproducible efficiencies in the range of up to 17%. In the absence of encapsulation, the devices exhibited stable performance characteristics during exposure to humid ambient air for 600 h. Furthermore, on flexible substrates, the 8 wt % PVP−perovskite samples provided for device efficiencies of ca. 15%. The devices retained ca. 73% of their efficiency after bending 1000 times with a bending radius of 0.5 cm.

Humidity‐Tolerant Roll‐to‐Roll Fabrication of Perovskite Solar Cells via Polymer‐Additive‐Assisted Hot Slot Die Deposition

“…Physical properties like flexibility are particularly important in flexible solar cells in terms of their applications and production process. Perovskite solar cells with improved flexibility have been reported previously . It has also been reported that polymer additives can be used to stabilize perovskite crystals against humidity‐assisted degradation .…”

Recent Advances of Device Components toward Efficient Flexible Perovskite Solar Cells

“…The structural formula ABX 3 provides numerous component combinations of tremendous versatility, [69][70][71][72][73][74][75][76][77][78][79] among which organic-inorganic halide perovskites are widely used in FPSCs. [80][81][82][83][84] Superior optoelectronic properties of the halide perovskite materials guarantee the prerequisites of achieving high-performance FPSCs. First, the strong optical absorption of halide perovskite materials across the visible spectra at the wavelength range of 300-800 nm has been revealed with high coefficients at an order of 10 5 cm À1 , one order of magnitude larger than that of the traditional monocrystalline silicon.…”

Recent developments in flexible photodetectors based on metal halide perovskite

“…etc. also have been added to the perovskite precursor solution during preparation process to enhance the crystallinity and stability of perovskite film . Generally, the presence of the additives is beneficial to produce smooth and uniform perovskite film with fewer flaw, which plays a significant role in improving photoelectric performances.…”