Tin-based perovskite solar cells (TPSCs) are strongly limited by Sn2+ oxidation and vacancy defects, which increase nonradiative losses and accelerate oxygen (O2)-related degradation. Here, mercaptoethylammonium bromide (ESABr) is introduced to regulate these coupled degradation processes. The thiol group buffers Sn2+/Sn4+ redox chemistry, while ammonium–iodide interactions stabilize the Sn-I framework and Br- compensates iodide-deficient sites. This combined regulation reduces Sn4+ accumulation and vacancy-associated trap states, suppressing defect-assisted recombination and improving carrier transport. More importantly, systematic simultaneous light and O2 (light/O2) aging measurements reveal slower electronic, chemical, and structural deterioration in ESABr-treated films, accompanied by reduced reactive O2 species generation. The optimized TPSCs achieve a power conversion efficiency of 15.09%. Encapsulated devices further exhibit a T80 lifetime of 896 h under maximum power point (MPP) tracking in ambient air, more than six times that of the control devices. These results connect redox and vacancy regulation with suppressed O2-related degradation, providing a mechanistic basis for improving the operational stability of tin perovskite photovoltaics.

Perovskite photovoltaic has garnered widespread attentions from the scientific and industrial community for the exceptional power conversion efficiency, low fabrication cost, straightforward processing, and structural versatility of the devices. However, conventional fabrication process of perovskite light‐absorbing films requires strictly controlled low‐humidity and low‐oxygen inert environment, which poses significant challenges for large‐area production and commercial scalability. Developing air‐stable perovskite precursor inks provides a useful approach to overcome the constraints of traditional preparation conditions. The present review first highlights the properties of perovskite precursor colloids and then provides a systematic overview of recent advances in air‐stable perovskite inks. A broad spectrum of strategies for bolstering the ambient stability of perovskite inks is comprehensively examined—encompassing solvent engineering, compositional optimization, and additive design. The review concludes by pinpointing the remaining challenges and charting future research pathways toward truly air‐processable perovskite materials, with the goal of accelerating both the technological maturation and the industrial‐scale deployment of perovskite photovoltaics.

Perovskite solar cells (PSCs) exhibit promising power conversion efficiencies and strong feasibility for large-scale manufacturing. However, the energy-level mismatch between the perovskite layer and charge transport layers impedes charge carrier collection at their interfaces and compromises device performance, an issue that is further exacerbated by the high density of defects on the perovskite surface. Herein, we report a facile molecular diffusion strategy that achieves the synergistic effects of gradient energy-level alignment and defect passivation at the upper interface of the perovskite layer. The functional molecule (2-(9H-carbazol-9-yl)ethyl)phosphonic acid (2PACz) reduces the surface roughness of the perovskite layer, fosters improved contact with the hole transport layer, and thereby facilitates hole injection and collection under gradient energy-level configuration. Additionally, the incorporation of the 2PACz molecule passivates surface defects on the perovskite layer, prolonging charge carrier lifetime and mitigating nonradiative recombination. Consequently, the PSCs modified with 2PACz exhibit a notable efficiency enhancement, rising from 19.17% to 22.45%. More importantly, the unencapsulated 2PACz-modified devices retain 82% of their initial efficiency following 2064 h of aging under inert conditions. This work thus presents a novel strategy for further boosting the performance and stability of PSCs.

A polymer-modulated crystallization strategy is developed to control perovskite crystallization and directly fabricate defect-suppressed perovskite films in high-humidity air (relative humidity, RH ≥ 70%).

Sputtered nickel oxide (NiOx) is an industrially compatible hole transport layer for perovskite solar cells (PSCs), yet its practical deployment is limited by interfacial instability arising from disordered Ni3+ species and unfavorable reactions with perovskite absorbers. Here, we introduce an in situ dissociative adsorption passivation (IDAP) strategy using bromoacetamide (BAA) to stabilize sputtered NiOx. In this approach, Br- ions act as site-blockers by coordinating with surface Ni, suppressing interfacial disorder and stabilizing Ni3+ species, while the amide group provides dual anchoring: N-H···O hydrogen bonding strengthens attachment to NiOx, and the carbonyl group (C═O) passivates the uncoordinated Pb2+ located at or near the interface between the NiOx and the perovskite films. These cooperative efforts reduce trap states, suppress interfacial redox reactions, and mitigate defect-driven degradation under thermal stress. PSCs incorporating BAA-NiOx achieve a champion power conversion efficiency (PCE) of 26.31% along with a certified PCE of 26.07%, while the larger-area PSCs (1 cm2) maintain 25.48% efficiency. This is one of the highest efficiencies reported for NiOx-based PSCs. In addition, the encapsulated cell retains 93% of its initial performance after 1500 h of continuous operation.

Thermal annealing improves the crystallinity of perovskite films and boosts their power conversion efficiencies (PCEs) in solar cells but also induces surface iodine loss and local lattice degradation. We demonstrate a molecular press annealing (MPA) strategy in which a 2-pyridylethylamine film is thermally and pressure-bonded to the perovskite surface. Real-time healing of iodine vacancies occurred during annealing and the lead-iodine framework was stabilized through optimized ligand engineering, resulting in enhanced structural integrity and long-term stability of perovskite films. This strategy enabled n-i-p perovskite solar cells to achieve a PCE of 26.6% (certified 26.5%). Notably, the devices retain 98.6 and 97.2% of their initial PCEs after 1617 hours of continuous operation under maximum power point tracking [ISOS-L-3 protocol, 85°C, 60% relative humidity (RH)] and 5280 hours of ambient storage (ISOS-D-1 protocol, room temperature, 10% RH).

Tin-based perovskite solar cells (Sn-PSCs) employing poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) gas hole transport layer represent one of the most promising architectures. However, their performance is severely limited by the insulating and hygroscopic...

Excess PbI2 is widely recognized as a critical factor in enhancing the efficiency of perovskite solar cells, yet the random aggregated PbI2 undergoes photodecomposition, and the migration of I- remains a critical bottleneck for long-term device operation. Herein, we report a PbI2 multi-interface reconstruction strategy enabled by the thermotropic liquid crystal molecule of 4-butoxybenzylidene-4-cyanoaniline (BBCA). During annealing, the dynamic phase transition of BBCA, along with its oriented arrangement and ordered self-assembled stacking, drives the formation of the (PbI2)2RbCl secondary phase and redistributes PbI2 from the buried interface and grain boundaries to the upper surface. This process realizes synergistic PbI2 reconstruction across multi-interfaces, effectively suppressing light- and heat-induced side reactions. Moreover, BBCA reduces defect density and non-radiative recombination losses, and optimizes the energy barrier, enhancing the PCE from 22.85% to 25.14%. Additionally, BBCA acts as a stabilizer by inhibiting both I- oxidation and migration under operation, thereby enhancing device stability. This work introduces a novel strategy for controlling PbI2 content and distribution across multi-interfaces while simultaneously suppressing ion migration, enabling highly efficient and stable perovskite solar cells.

Perovskite solar cells (PSCs) are a revolutionary photovoltaic technology with lab-recorded power conversion efficiencies (PCE) over 27

Solvents play a pivotal role in regulating the phase transformation behavior and film quality of all-inorganic CsPbBr3 perovskites. However, the effect of solvents on crystallization kinetics has long been overlooked, primarily owing to the scarcity of suitable solvents for processing its precursor materials. Although water (H2O) and methanol (MeOH) have been explored as candidate solvents, their utilization usually entails complex fabrication procedures and tends to disrupt the crystalline structure of the resulting CsPbBr3 films. Herein, we systematically elucidate the impacts of solvent polarity on CsPbBr3 formation and propose an effective strategy using formic acid (Fa) to achieve precise control over the perovskite composition. Fa with an optimized polarity efficiently enhances CsBr solubility while mitigating phase degradation triggered by residual solvent retention. This dual benefit facilitates the fabrication of high-quality perovskite films with elevated phase purity and reduced defect density. Consequently, the resultant perovskite solar cells deliver a champion power conversion efficiency (PCE) of 6.09%, outperforming counterparts processed with methanol (5.56%) and deionized water (4.79%). Moreover, Fa-treated perovskite films exhibit pronounced improvements in both phase homogeneity and ambient stability. This work thus establishes a versatile strategy to further boost the performance metrics of all-inorganic perovskite solar cells.

The electron transport layer (ETL) in perovskite solar cells (PSCs) acts both as a functional layer and a substrate for perovskite crystallization, which exerts a profound influence on interfacial quality and overall device performance. Although colloidal dispersions of tin oxide (SnO2) offer facile processing, the complex composition of these dispersions inevitably introduces defects within the ETL. In this work, we explore sputtering as a deposition method for SnO2 ETLs and systematically investigate the distinct mechanisms governing interfacial dynamics relative to conventional solution-based processes. Complementary characterization experiments were conducted to elucidate the underlying physicochemical origins of these differences. Notably, the optimized sputtered SnO2-based devices achieved a power conversion efficiency (PCE) of 21.41%, despite the formation of small-grained perovskite films atop sputtered SnO2. We find that the poor interfacial characteristics of sputtered SnO2 ETLs compromise the long-term stability of the resultant devices. Thus, substrate modification or sublayer engineering strategies are proposed as promising avenues for further performance optimization of sputtered SnO2-based PSCs.

CsPbIBr2 has emerged as a highly promising material for optoelectronic applications, owing to its appropriately tuned bandgap and exceptional thermal stability. However, the practical fabrication of polycrystalline CsPbIBr2 thin films is severely constrained by the low solubility and poor stability of their precursor solutions. Here, we demonstrate a crown ether coordination strategy to enhance colloidal precursor reliability and elucidate the dissolution mechanism. We find that the soft-base characteristic of I- and the borderline base characteristic of Br- facilitate the formation of coordination complexes, PbXn2-n & centerdot;DMSO (X = I/Br). The incorporation of 15-Crown-5 stabilizes the colloidal dispersion through interactions with Cs+ and Pb2+, thereby accelerating the dissolution of CsBr, increasing the zeta potential of colloids, and suppressing their aggregation and sedimentation. As a result, the obtained CsPbIBr2 films exhibit enhanced crystallinity, reduced defect density, and homogeneous charge distribution. The corresponding devices achieve a 50% increase of efficiency from 6.0 to 9.1% and demonstrate improved device stability under humid conditions. This work establishes a paradigm for integrating halide ion chemistry and crown ether coordination to overcome the limitations of precursor stability, thereby paving the way for high-performance CsPbIBr2-based optoelectronics.

High-performance inverted perovskite solar cells (PSCs) rely critically on high-quality interfaces and efficient bulk defect passivation. However, achieving simultaneous optimization of charge extraction and lattice stabilization through functional molecular modifiers remains a persistent challenge in the field. Herein, we demonstrate a multidentate molecular anchoring strategy leveraging tripodal phosphonic acid molecules to regulate the co-deposition dynamics of the perovskite absorber and hole transport layer. The trifurcated phosphonic acid moieties enable robust multidentate chemisorption onto the glass substrate, yielding an interface with face-on pi-stacking orientation that facilitates optimal band alignment and suppresses interfacial charge recombination. Concurrently, these molecules segregate preferentially to perovskite grain boundaries, where they engage in coordinative passivation of undercoordinated Pb2 + defects. This dual-functional design constructs a coherent charge-transport network that synergistically enhances interfacial hole extraction while mitigating ion migration and bulk defect formation. The resulting PSCs deliver a certified power conversion efficiency of 26.35%, accompanied by exceptional operational stability: retaining 82% of their initial performance after 1000 h of thermal stability test (85 degrees C) and 86% after 1000 h of maximum power point tracking. This work establishes critical insights into molecular-mediated interface stabilization, providing a generalized framework for the rational design of functional molecules for optoelectronic devices.

As global energy demand continues to rise and the need for environmental conservation grows more urgent, solar energy has attracted substantial attention owing to its inherent cleanliness and sustainability.Perovskite solar cells (PSCs), an innovative photovoltaic technology, have shown significant improvements in photoelectric conversion efficiency (PCE) since their introduction.Nevertheless, significant challenges remain in enhancing efficiency and ensuring long-term stability.Naturally abundant and environmentally benign carbon materials represent a promising alternative.Incorporating carbon materials into PSCs can yield beneficial effects, such as controlling the crystallization rate of the perovskite layer, improving carrier transport properties, and realizing interface modification between various functional layers.This article systematically reviews the application of carbon materials in PSCs, including carbon nanotubes, carbon dots, carbon nanofibers, fullerenes, and their derivatives.

Perovskite photovoltaic has garnered widespread attentions from the scientific and industrial community for the exceptional power-conversion efficiency, low fabrication cost, straightforward processing, and structural versatility of the devices. However, conventional fabrication process of perovskite light-absorbing films requires strictly controlled low-humidity and low-oxygen inert environment, which poses significant challenges for large-area production and commercial scalability. Developing air-stable perovskite precursor inks provides a useful approach to overcome the constraints of traditional preparation conditions. The present review first highlights the properties of perovskite precursor colloids, then provides a systematic overview of recent advances in air-stable perovskite inks. A broad spectrum of strategies for bolstering the ambient stability of perovskite inks is comprehensively examined-encompassing solvent engineering, compositional optimization, and additive design. The review concludes by pinpointing the remaining challenges and charting future research pathways toward truly air-processable perovskite materials, with the goal of accelerating both the technological maturation and the industrial-scale deployment of perovskite photovoltaics.

Hole transport layers (HTLs) play a pivotal role in governing the photovoltaic performance of perovskite solar cells (PSCs). However, conventional doped organic HTLs are plagued by inherent drawbacks, including ion migration, moisture absorption, and phase separation, issues that severely compromise device stability and performance. Herein, we develop an all-evaporated dopant-free HTL featuring a bilayer architecture, fabricated via the sequential evaporation of spiroOMeTAD and copper phthalocyanine (CuPc). The integration of small-molecule interfacial modification furnishes a uniform deposition platform for CuPc, thereby enabling precise modulation of its microstructural arrangement within the film. Furthermore, this rationally designed bilayer structure elevates the electron transport barrier and mitigates interfacial electron recombination losses. Consequently, the devices engineered with this bilayer HTL deliver a champion power conversion efficiency (PCE) of 19.8%, representing one of the highest reported performance for evaporated dopant-free HTLs. Critically, the devices incorporating the bilayer HTL exhibit significantly improved operational stability compared to conventional devices employing doped spiroOMeTAD HTLs. This work provides an alternative strategy for the rational design of dopant-free HTLs and paves a viable pathway toward further boosting the photovoltaic performance and operational stability of thermally evaporated HTLs for PSCs.

Perovskite solar cells (PSCs) have achieved a power conversion efficiency (PCE) of over 27%, but further improvements of both PCEs and stability are needed for commercialization. One of the key factors hindering their development is the unpredictable residual strain in perovskites. The unstable octahedral structure of the perovskite cage leads to easy changes in bond lengths, bond angles, and crystal structure. It in turn generates, accumulates, and causes the non-uniform distribution of residual strain, ultimately affecting device performance. Therefore, given the versatility and precise tunability, residual strain engineering provides an effective pathway to optimize the performance of PSCs. This review summarizes the causes of residual strain during device fabrication and operation, qualitative/quantitative/auxiliary characterization methods, and various effective strain regulation methods in the past two years. Finally, unresolved scientific issues and future research directions in strain engineering are discussed. This comprehensive review aims to provide researchers with the latest advances in strain engineering, deepen fundamental understanding of strain effects, and eventually help enhance the performance of PSCs.

Nickel oxide (NiOx) is among the most widely used hole-transport materials (HTMs) for inverted perovskite solar cells (PSCs), yet its substantial surface defects compromise the device's performance and long-term stability. Despite the development of various surface engineering strategies, the underlying mechanism governing interfacial dynamics is incompletely understood. Herein, we systematically investigate the structural roles of molecular passivators in tailoring NiOx properties, with a focus on elucidating the distinct mechanisms of two structurally analogous modifiers: the polymer polyvinylpyrrolidone (PVP) and the small-molecule N-methylpyrrolidone (NMP). The results demonstrate that the pronounced steric hindrance arising from the long polymer chains of PVP constructs a physical barrier, which detrimentally impacts charge transport and perovskite crystallization. Conversely, NMP capitalizes on its small molecular size and chemical reactivity to achieve directional selective passivation. This chemical modification not only effectively optimizes interfacial properties but also facilitates the crystallization of perovskite films. As a result, the NMP-modified PSCs achieve a power conversion efficiency (PCE) of 20.89%, in contrast to 18.52% for their PVP-modified counterparts. Notably, the unencapsulated NMP-modified device retains 93% of its initial efficiency following 1800 h of storage at 25 °C under a nitrogen atmosphere. This work sheds light on the intrinsic correlation between molecular structure and device performance, thereby offering valuable guidance for further optimization of both the efficiency and long-term stability of PSCs.

ABSTRACT While large π‐conjugated nanoribbons possess highly tunable electronic properties, their potential in high‐performance organic photovoltaics (OPVs) remains largely untapped. Herein, we report a π‐extended nanoribbon‐like electron acceptor, PDIY, featuring a molecular length of 4.85 nm (11 fused rings) and near‐infrared absorption extending to 900 nm. PDIY is engineered with a perylene diimide core fused to dual rylene units and end‐capped with Y‐type acceptor moieties. The rigid conjugated framework effectively suppresses conformational/vibronic relaxation, weakens electron‐phonon coupling, and yields an intrinsically low non‐radiative voltage loss (Δ V nr ) of 0.146 eV, among the lowest values reported to date, thereby enabling higher open‐circuit voltage. Despite its large size, the twisted geometry of PDIY leads to a unique “low crystallinity, strong aggregation” behavior. This allows PDIY to serve as a potent morphology‐directing additive that acts in a manner consistent with heterogeneous nucleation, inducing the formation of robust, large‐diameter fibrillar networks within bulk‐heterojunction blends. Consequently, the integration of PDIY yields a simultaneous enhancement across all photovoltaic parameters, boosting power conversion efficiencies (PCEs) from 19.62% to 20.57%. This work establishes twisted nanoribbon‐like acceptor as a versatile molecular platform for the dual regulation of excited‐state dynamics and active‐layer morphology in next‐generation OSCs.

Perovskite solar cells (PSCs) possess enormous potential and demonstrate promising commercialization prospects. However, the fabrication of perovskite films has been largely restricted to inert environments owing to the material's high sensitivity to moisture and oxygen. Herein, we propose a surfactant-modulated pre-nucleation strategy to enable the ambient fabrication of high-performance perovskite films, while systematically elucidating the interaction mechanism between a multifunctional phosphatidylcholine-based zwitterionic surfactant and perovskite colloids. By regulating the aggregation behavior of perovskite colloids, the energy barrier for nucleation is substantially reduced. This not only accelerates nucleation kinetics but also effectively alleviates the adverse effects of ambient moisture during film fabrication. Furthermore, the surfactant inherently forms a moisture-resistant protective layer on the film surface. Benefiting from this synergistic strategy, high-quality perovskite films with ultralow defect density were successfully fabricated under ambient air conditions. Consequently, the resulting PSC devices achieve a remarkable power conversion efficiency (PCE) of 21.43% and exhibit excellent long-term stability, retaining 93% of their initial efficiency after 2000 h of storage in an environment with 20%-30% relative humidity.