Metal halide perovskites have raised huge excitement in the field of emerging photovoltaic technologies. The possibility of fabricating perovskite solar cells (PSCs) on lightweight, flexible substrates, with facile processing methods, provides very attractive commercial possibilities. Nevertheless, efficiency values for flexible devices reported in the literature typically fall short in comparison to rigid, glass-based architectures. Here, a solution-processable fullerene derivative, [6,6]-phenyl-C61 butyric acid n-hexyl ester (PCBC6), is reported as a highly efficient alternative to the commonly used n-type materials in perovskite solar cells. The cells with the PCBC6 layer deliver a power conversion efficiency of 18.4%, fabricated on a polymer foil, with an active area of 1 cm 2. Compared to the phenyl-C61-butyric acid methyl ester benchmark, significantly enhanced photovoltaic performance is obtained, which is primarily attributed to the improved layer morphology. It results in a better charge extraction and reduced nonradiative recombination at the perovskite/ electron transporting material interface. Solution-processed PCBC6 films are uniform, smooth and displayed conformal capping of perovskite layer. Additionally, a scalable processing of PCBC6 layers is demonstrated with an ink-jet printing technique, producing flexible PSCs with efficiencies exceeding 17%, which highlights the prospects of using this material in an industrial process.

PCBM crosslinked with 1,6-diazidohexane (DAZH) was introduced to solve the solvent incompatibility of depositing a solution processed perovskite layer onto it.

Flexible perovskite solar cells (f‐PSCs) offer attractive commercial prospects in the near future, enabled by new value propositions, such as mechanical flexibility, or high specific powers. The long‐term reliability of these devices requires appropriate encapsulation to prevent degradation caused by environmental factors. Here, a lamination protocol is developed, incorporating adhesive materials, barrier foils, and edge sealants, which results in a robust device hermitization. By applying the developed procedure to three different perovskite solar cell configurations (p‐i‐n with carbon, p‐i‐n with silver, and n‐i with carbon), fabricated with large active areas (1 cm2), the universality of this approach is demonstrated. The best devices preserved over 85% of the initial performance after a sequence of accelerated aging tests based on industry standards (compliant with the IEC 61215 and IEC 61646) comprised of 1400 h of damp heat, 50 thermal cycles, and 10 cycles of the humidity‐freeze test.

Perylene diimide derivatives with different functional groups (OR) in the bay position were synthesised (PDI-1, OR = OC6H4OMe; PDI-2, OR = OC6H4CH2CH2NHBoc; PDI-3, OR = OC6H4CO2Me) and their optoelectronical properties...