Hysteresis-free and highly efficient CH₃NH₃PbI₃ perovskite solar cells employing a compact C₆₀ material as an electron transport layer have been developed for the first time using both rigid glass and plastic substrates.

We present a simple method for the fabrication of robust superomniphobic surfaces with high transmittance (>90%) and durability (<6 months). The method consists of direct micromolding of mushroom-like micropillars and C₄F₈ gas surface treatment. Such re-entrant structures were found to be highly resistant against wetting by various liquids and oils with a wide range of surface tensions from 22.3 (ethanol) to 72.1 mN m⁻¹ (water). Optimal structural parameters were derived based on the measurements of static contact angle and contact angle hysteresis.

We report a theoretical analysis on the crystallization of CH ₃ NH ₃ PbI ₃ and the control of grain sizes by varying the two-step reaction temperature from −10 °C to 50 °C based on the present analysis.