Shudi Qiu

Compared to vacuum‐deposited electrodes of metal or metal oxides, printable carbon electrodes (CEs) offer a more sustainable approach toward commercialization of perovskite solar cells (PSCs). Significant attention has been paid to the N‐i‐P carbon‐based PSCs (C‐PSCs), owing to the favorable alignment of CEs work‐functions with perovskite valence band. In contrast, the P‐i‐N structured PSCs employing carbon as electron‐collecting contact has been rarely explored, primarily due to the presence of large interfacial barrier. Here, we eliminate the stubborn interfacial barriers by means of increasing free carrier density of electron transport layer (ETL) in conjugation with the insertion of a non‐conducting metal thin layer between ETL and CEs. The synergistic strategies enable the preparation of efficient P‐i‐N C‐PSCs with a record efficiency of 22.79% (certified 21.34%). The detailed life cycle cost and assessment reveal that our P‐i‐N C‐PSCs outperform metal‐electrode counterparts in both cost‐effectiveness and environmental impact.

Flexible lead‐halide perovskite solar modules with carbon electrodes (C‐fPSMs) are promising for printed photovoltaics due to their low cost and compatibility with roll‐to‐roll (R2R) fabrication. However, the mechanical fragility of microcrystalline perovskite films, arising from their high grain‐boundary density, limits their practical application. Here, we report a vapor‐phase grain‐boundary anchoring strategy via thiol vapor annealing to molecularly toughen printed perovskite layers. Thiol molecules interact with intermediate species and preferentially anchor at surfaces and grain boundaries, reprogramming crystallization across the film. This chemomechanical conditioning promotes grain growth, reduces trap density, and transforms the deformation behavior from brittle fracture to ductile strain accommodation, as evidenced by reduced Young's modulus, increased yield strain, and significantly enhanced fracture toughness. As a result, treated devices retain 93% of their initial performance after 25 000 bending cycles, representing a new benchmark for flexible perovskite cells. In addition, improved film uniformity and interfacial contact enable power conversion efficiencies of 15.7% for R2R‐printed cells and 12.1% for modules (20.25 cm ² ), with scalability demonstrated up to 900 cm ² (17.26%). This work provides a scalable strategy to simultaneously enhance mechanical robustness and photovoltaic performance.

Flexible lead‐halide perovskite solar modules with carbon electrodes (C‐fPSMs) are promising for printed photovoltaics due to their low cost and compatibility with roll‐to‐roll (R2R) fabrication. However, the mechanical fragility of microcrystalline perovskite films, arising from their high grain‐boundary density, limits their practical application. Here, we report a vapor‐phase grain‐boundary anchoring strategy via thiol vapor annealing to molecularly toughen printed perovskite layers. Thiol molecules interact with intermediate species and preferentially anchor at surfaces and grain boundaries, reprogramming crystallization across the film. This chemomechanical conditioning promotes grain growth, reduces trap density, and transforms the deformation behavior from brittle fracture to ductile strain accommodation, as evidenced by reduced Young's modulus, increased yield strain, and significantly enhanced fracture toughness. As a result, treated devices retain 93% of their initial performance after 25 000 bending cycles, representing a new benchmark for flexible perovskite cells. In addition, improved film uniformity and interfacial contact enable power conversion efficiencies of 15.7% for R2R‐printed cells and 12.1% for modules (20.25 cm ² ), with scalability demonstrated up to 900 cm ² (17.26%). This work provides a scalable strategy to simultaneously enhance mechanical robustness and photovoltaic performance.

Perovskite solar cells (PSCs) experience significant photovoltage losses due to nonradiative recombination, especially in p–i–n devices with Fullerene C ₆₀ as the electron transport layer (ETL), which limits device performance. To tackle this issue, we propose a strategy that synergistically suppresses nonradiative recombination at the perovskite/C ₆₀ interface by employing a 2D heterointerface with a two‐site anchor bridge, which reduces the surface defect density. This process elevates the fermi level and enhances the electric field, facilitating electron extraction at the perovskite/C ₆₀ heterointerface. As a result, nonradiative recombination at this electron‐selective perovskite contact is greatly suppressed. p–i–n PSCs fabricated using this interface engineering approach achieved a power conversion efficiency (PCE) of 26.32% and demonstrated excellent stability under continuous maximum power point tracking, along with an open‐circuit voltage (Voc) of 1.217 V. This broadly applicable and scalable approach further delivers an impressive V oc of up to 1.368 V in wide‐bandgap (1.8 eV) devices. Overall, the strategy offers a viable pathway toward efficient and stable inverted PSCs, demonstrating broad compatibility with diverse perovskite compositions.

Monolithic perovskite–organic tandem solar cells (P–O TSCs) establish a mutual protection system, which enables high-efficiency P–O TSCs (25.12%) to achieve exceptional operational stability, retaining over 91% after 1000-hour illumination.

Coupling in situ monitoring with supersaturation-rate calculations, we employ a facile solvent-engineering strategy to balance supersaturation rate and coordination capability, enabling 25.38% PSCs (0.09 cm ² ) and a 23.22% mini-module (21.84 cm ² ).

Ligand engineering is an effective method to reduce defects in perovskite solar cells (PSCs) and to enhance efficiency.

Guided by phase-field simulations, a pre-coated 2D perovskite layer enables the growth of void-free perovskite layers over one-micron-thick, achieving high-efficiency, fully printed solar cells.

Advanced phase field simulations of solution-based perovskite film formation are used to obtain information on film creation that is experimentally challenging to access. This includes the explanation, of why perovskite films should dry quickly.