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Perovskite light‐emitting diodes (PeLEDs) are promising technologies for advanced display and lighting source applications. Alongside tremendous efforts to improve efficiency, developing flexible devices could potentially enable PeLEDs compatible with wearable, foldable, bio‐integrated, and other intriguing functionalities. However, the flexible PeLEDs currently have not received enough attention. The overall performance still lags behind the rigid one, mainly attributed to the lack of mechanically stable perovskite thin films with desirable optical and electrical properties. Herein, a self‐healing strategy to achieve flexible perovskite films with improved mechanical reliability and optoelectrical properties is proposed. A multi‐functional silane molecule of (3,3,3‐trifluoropropyl) trimethoxysilane (TFPTMS) is incorporated into a perovskite precursor, which could undergo an in situ cross‐linking process and generate a flexible Si–O–Si network within the perovskite films. In addition, the reversible hydrolysis and condensation reactions and the fluorinated alkyl chains endow the perovskite films with self‐healing capability. Accordingly, the synergistic influences contribute to high‐efficiency flexible PeLEDs with an external quantum efficiency (EQE) of 16.2%. Moreover, 75% of the initial efficiency value is reserved even after 1000 bending cycles. This work paves a way to rationalize flexible perovskite thin films for various optoelectronic applications.

Extensive efforts have been made to develop wide‐bandgap metal compound‐based carrier‐selective contacts to improve the performance of crystalline silicon (c‐Si) solar cells, by mitigating the deleterious effects of metal–Si contact directly. Herein, thermally evaporated wide‐bandgap strontium oxide (SrO x ) is exploited as an electron‐selective contact for c‐Si solar cells. Benefiting from a lower work function (3.1 eV) of SrO x , a strong downward band‐bending is achieved at the n‐type c‐Si/SrO x interface, enabling the electron‐selective transport characteristic. Thin SrO x films simultaneously provide moderate surface passivation after annealing and enable a low contact resistivity on c‐Si surfaces. By the implementation of a single‐dielectric‐layer SrO x ‐based rear contact, a champion power conversion efficiency of 20.0% is realized on the n‐type c‐Si solar cell featuring an intriguing fill factor of 82.8%. Moreover, electron‐selective SrO x contact is demonstrated to show high thermal stability up to 500 °C. The SrO x layer formed by a facile thermal evaporation process presents a unique opportunity to develop highly efficient and low‐cost c‐Si solar cells.

photovoltaic modules are widely used in ground-mounted solar power plants or rooftop PV installations. [2,3] However, there is increasing emphasis on the visual aesthetics of solar modules, [4,5] such as building-integrated photovoltaics (BIPV), which exhibit the potential to both power and decorate urban architecture owing to their low space requirements. Colored PV panels are typically mounted on the roof or glass facades of buildings which improve the visual aesthetics of the building. Moreover, aesthetically designed PV technology is also popular in productintegrated solar cells, where it can power electronics and simultaneously meet the overall visual design of the product. [6] The light escaping from the cell surface causes a colored appearance due to cell current loss owing to less light absorption. Thus, a tradeoff between colored appearance and device performance should be realized. Therefore, in colored PV panels, it is challenging to improve the visual aesthetics while preserving initial power conversion efficiency (PCE). [7] One promising method is to minimize the reflection range of colored PV cells to meet high color purity and low photon loss.Most PV cells exhibit a black or dark-blue appearance because of the low-reflection optical design for a high current Colored solar panels, realized by depositing various reflection layers or structures, are emerging as power sources for building with visual aesthetics. However, these panels suffer from reduced photocurrent generation due to the less efficient light harvesting from visible light reflection and degraded power conversion efficiency (PCE). Here, color-patterned silicon heterojunction solar cells are achieved by incorporating luminescent quantum dots (QDs) with high quantum yields as light converters to realize an asthenic appearance with high PCE. It is found that large bandgap (blue) QD layers can convert UV light into visible light, which can notably alleviate the parasitic absorption by the front indium tin oxide and doped amorphous silicon. Additionally, a universal optical path model is proposed to understand the light transmission process, which is suitable for luminescent down-shift devices. In this study, solar cells with a PCE exceeding 23.5% are achieved using the combination of a blue QD layer and a top low refractive index antireflection layer. Based on our best knoledge,the obtained PCE is the highest for a color-patterned solar cell. The results suggest an enhanced strategy involving incorporation of luminescent QDs with an optical path design for high-performance photovoltaic panels with visual aesthetics.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202208042.

Solution‐processed white quantum dot light‐emitting diodes (WQLEDs) hold great promise for lighting and backlight applications. Stacked blue/green/red quantum dots (QDs) films as an emitting layer through the layer‐by‐layer deposition offer a simple way to realize WQLEDs. However, the redissolution issue rising from the deposition of the adjacent QDs layers prevents the fabrication of high‐quality multilayer emissive layers. Here, a ligand exchange strategy is developed to improve the solvent‐resistance of the QDs films by exposing the QDs films in a trace acid environment. The dissociated hydrions from the acid protonate the aliphatic ligands and desorb them away from QDs’ surface, leaving space for inorganic ions to anchor onto the QDs’ surface. Importantly, the trace acid does not destroy the morphological properties of QDs films and reserves their initial photoluminescence efficiency. In addition, the charge transporting ability of the QDs is enhanced on account of the replaced inorganic ligands. As result, the stacked WQLEDs display pure white emission with Commission International de I'Eclairage coordinates of (0.34, 0.33), and impressive external quantum efficiency of 9.1% has been demonstrated. This solid‐phase ligands exchange strategy provides an alternative way to engineer the surface of QDs for efficient optoelectronics.

To increase the efficiency of silicon heterojunction (SHJ) solar cells (SCs), it is paramount to enhance the utilization of sunlight by light management. In this study, the dependences of weighted reflectance and thus generation current (JG) for SHJ SCs on different anti-reflective structures are displayed by OPAL2 simulation tool. According to this, SiNx and SiO2 films are deposited on front of Indium tin oxide (ITO) as multilayer anti-reflection coatings (ARC). It is demonstrated experimentally that the photovoltaic performance of SHJ solar cells can be significantly improved by multilayer anti-reflection coatings Especially, with 90/21/40 nm SiO2/SiNx/ITO anti-reflective layer structure, the reflectance of SHJ solar cell is reduced as low as 0.94%, and JG is shown to be increased by 4.34% compared to the common solar cells. This work shows a promising and cost-effective way to achieve higher light utilization and thus promotes photovoltaic characteristics for SHJ solar cells.