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Monolithic perovskite/silicon tandem solar cells are widely regarded as the next-generation, low-cost, high-efficiency photovoltaic technology. However, achieving high-quality wide-bandgap perovskite top cells on industrial textured silicon, particularly using hybrid two-step deposition methods that combine sequential co-evaporation and solution processing, remains a major challenge. In this work, we introduce a healing intervention strategy that significantly tailors perovskite film growth and enhances the film quality on textured silicon substrates. By applying an MASCN solution to heal the as-prepared films, which induces secondary crystal growth to enhance overall perovskite crystallization, we obtain a conformal perovskite layer characterized by columnar grains that extend through the full film thickness. The resulting 1.68 eV wide-bandgap perovskite solar cells achieve a champion efficiency of 21.1%, contributing to a certified stabilized tandem efficiency of 30.77% and an impressive Voc of 1.915 V over an active area of 1.164 cm & sup2;. Notably, an encapsulated device retains its initial performance after 3400 hours of continuous maximum power point tracking under one-sun illumination in ambient conditions, representing the excellent stability in perovskite/silicon tandem cells reported to date.

Scalable fabrication of wide-band-gap perovskite sub-cells under ambient conditions is essential for commercial perovskite/silicon tandem photovoltaics. However, uncontrolled ambient moisture renders crystallization unmanageable and triggers irreversible surface decomposition. To address this, we innovate a wet-film intervention strategy using bifunctional n-butylammonium thiocyanate (nBASCN) to regulate perovskite crystallization and mitigate the adverse impact of moisture. The strategic incorporation of SCN⁻ into wet films enables homogeneous secondary grain growth with enhanced crystallinity and grain size by decoupling the crystallization process from environmental humidity. Optimally tailored nBA⁺ cations balance hydrophobicity with SCN⁻-assisted crystallization, constructing a self-volatile 2D hydrophobic barrier that effectively suppresses moisture-induced surface degradation without compromising charge transport. As a result, we achieved a remarkable efficiency of 30.71% (certified 30.51%) for perovskite/silicon tandem devices (1.1664 cm²) and 29.09% for large-area tandem devices (16 cm²), representing the highest efficiency of perovskite/silicon tandem solar cells via scalable fabrication in ambient air.

Monolithic perovskite/perovskite/silicon triple-junction solar cells offer higher theoretical efficiency than their two-junction counterparts. However, the phase instability of ultrawide-bandgap perovskites remains a major obstacle to further improve the efficiency and stability of triple-junction devices. Here, we introduce 1,4-phenylenediamine dihydriodide into the 1.93-eV bandgap perovskite, which significantly increases the ion migration barrier and suppresses phase segregation through strong interactions with the perovskite lattice. Combined with a post-treatment using 3-(methylthio)propylamine hydroiodide to modify the perovskite surface, we achieved a certified efficiency of 26.18% for the triple-junction solar cell, with an impressive open-circuit voltage of 3.148 V on an aperture area of 1.17 cm². Notably, the encapsulated devices retained 96% of their initial performance after 1500 hours of continuous maximum power point tracking under one-sun illumination in ambient conditions, representing the notable stability in perovskite/perovskite/silicon triple-junction cells reported to date.

Industrially textured perovskite/silicon tandem solar cells are among the most promising candidates for future low-cost photovoltaic deployment. Air-annealing is an inevitable process to fabricate high-quality perovskite films during the hybrid two-step deposition method. However, this process often leads to severe perovskite decomposition on the surface because of moisture exposure and high-temperature. To address this issue, a stabilizing additive-dimethylphenethylsulfonium iodide (DMPESI)-is introduced into the organic salt solution, forming a hydrophobic internal encapsulation layer. As a result, the perovskite surface decomposition is effectively suppressed during the air-annealing process and the resulting perovskite films exhibit significantly enhanced film stability and quality. Consequently, the industrially textured perovskite/silicon tandem solar cells delivered an impressive efficiency of 30.49% (1.21 cm2). Moreover, encapsulated tandem devices retained 84% of their initial efficiency after nearly 1800 h of maximum power point tracking (MPPT) (ISOS-L-1) and 80% after 723 h of damp heat test (ISOS-D-3).

The most efficient and stable perovskite solar cells typically contain lead compounds as a key component in the light-absorbing layer. To advance the commercialization of perovskite photovoltaics, it is crucial to address sustainability concerns regarding the use of toxic lead. In this work, we have developed a straightforward lead recycling pathway that converts lead compounds from lead-acid batteries into lead iodide. Purity analyses of the resulting lead iodide and the direct fabrication of perovskite solar cells demonstrate that the recycled lead iodide matches the quality of commercially available products. Most importantly, establishing this efficient lead recycling process not only supports sustainable recycling and resource utilization in a circular materials flow but also promotes the future development of perovskite photovoltaics.

Low-temperature-processed carbon-based perovskite solar cells (C-PSCs) are a potential candidate for industrial development, due to their low cost, high stability, and easy preparation methods. However, their power conversion efficiencies still lag behind that of metal-contact-based PSCs, due to poor compatibility of the carbon electrode with the underlying layers. Here, we introduce a doping-free poly(3-hexylthiophene) (P3HT) hole-transport layer deposited from chloroform to improve solar cell performance of PSCs that are prepared in ambient air. The resulting P3HT films have a lower roughness and a higher conductivity. A champion device with power conversion efficiency of 19.4% was obtained with negligible hysteresis and a remarkably enhanced fill factor (FF) of 80.2%. Unencapsulated devices maintained 70% of initial efficiency value after 350 hr under thermal stress at 85 degrees C in dark and ambient air.

Semi-transparent photovoltaics (STPVs) have attracted increasing attention owing to their ability to seamlessly integrate power generation with light transmission. They can complement traditional opaque photovoltaics, significantly broadening their potential applications. Although STPVs have achieved great progress driven by advances in material engineering and device engineering, they still encounter substantial challenges for real-world deployment. This review summarizes the recent progress in STPV technologies, highlights the challenges they face in practical applications, and provides a detailed analysis of the factors affecting their performance improvements. We explore how innovations in active layer manipulation, transparent electrode design, interfacial engineering, optical structures and tandem architectures contribute to enhancing STPV performance. Furthermore, we summarize the emerging applications of STPVs in various fields, such as building integrated photovoltaics, agricultural photovoltaics, bioelectronics, wearable electronics and optical wireless communication. Overall, this review offers valuable insights into materials science, physics and optoelectronics.

All-perovskite tandem solar cells are emerging at a fast rate because of their potential to exceed efficiencies of Si-perovskite tandems, in combination with faster manufacturing, lower cost, and the ability to be processed on flexible substrates. Mixing halides is a key to achieve wide-bandgap absorbers, which however suffer from halide segregation under illumination, resulting in lowering of the bandgap. To tackle this problem, butylamine (BA) has been added to the perovskite precursor solution and is found to react with the formamidinium (FA) cation, producing N-butylformamidinium (BuFA+), which accumulates at the perovskite surface and grain boundaries. The creation of the BuFA cation results in suppressed halide segregation and improved crystallization. Density functional theory calculations propose the reduction of halide defect formation upon the addition of BA, being a key to stabilize mixed-halide perovskites. Lastly, we observe a more stable performance of single junction p-i-n perovskite solar cells with the addition of BA under constant illumination at 65 degrees C.

The increasing global concerns about energy shortages and environmental pollution are driving the development of materials for clean energy conversion. Among various materials, lead halide perovskite solar cells (PSCs) have emerged as promising candidates for next-generation photovoltaic (PV) technologies. However, the use of toxic lead in high-efficiency perovskite devices raises sustainability concerns, particularly due to the risk of environmental contamination from lead leakage. Given the projected growth of the perovskite photovoltaic market, effective management of lead toxicity is essential for the safe deployment of this technology. This review explores the latest developments in lead encapsulation strategies, including both external and internal encapsulation materials, aimed at mitigating lead leakage and enhancing the safety and sustainability of perovskite photovoltaics. Additionally, it also discusses various recycling solutions necessary to establish a sustainable closed-loop lead management system. These approaches not only recycle lead but also reclaim other materials, promoting the circular use of resources and advancing the competitiveness of perovskite PV technologies.image

Perovskite solar cells (PSCs) hold significant promise as the next-generation materials in photovoltaic markets, owing to their ability to achieve impressive power conversion efficiencies, streamlined fabrication processes, cost-effective manufacturing, and numerous other advantages. The utilization of self-assembled monolayer (SAM) molecules has proven to be a significant success in enhancing device efficiency and extending device stability. This review highlights the dual use of SAM molecules in the realm of PSCs, which can not only serve as charge transport materials but also act as interfacial modulators. These research endeavors encompass a wide range of applications for various SAM molecules in both n-i-p and p-i-n structured PSCs, providing a deep insight into the underlying mechanisms. Furthermore, this review proposes current research challenges for future investigations into SAM materials. This timely and thorough review seeks to provide direction and inspiration for current research efforts dedicated to the ongoing incorporation of SAMs in the field of perovskite photovoltaics. Self-assembled monolayer (SAM) molecules are extensively employed in perovskite solar cells, serving both as charge transport materials and interfacial modulators. These molecules play a crucial role in adjusting surface energy levels, reducing interfacial trap defects, and enhancing perovskite crystallization quality, thereby leading to improved performance and stability of perovskite solar cells. image