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Perovskite/silicon tandem solar cells (TSCs) have aroused much attentions in recent years. One of keys for achieving highly efficient and stable TSCs is to guarantee effective charge transfer, especially on the rough textured silicon substrate due to the poor adhesion between interlayers. Here, a 2‐fluoroisonicotinic acid (2‐FNA) additive that possesses fluorine (‐F), carboxylic acid (‐COOH), and pyridine nitrogen as functional groups in the perovskite precursor to assist the crystallization process is utilized. It shows that 2‐FNA can efficiently reduce the defects and suppress non‐radiative recombination of perovskite layers by bonding with the uncoordinated Pb2+ ions, formamidinium (FA+), and halide vacancies, leading to notably prolonged carrier lifetime. Most importantly, this found that 2‐FNA aids in the formation of better interfacial contact between the perovskite and C60 layer on top, thus enhancing the interfacial electron extraction therein, eventually leading to an increased power conversion efficiency (PCE) of 28.61% on champion perovskite/silicon TSCs from 27.08% on control counterparts. This work provides a practical route to further advance the PV performance and applicability of perovskite/silicon TSCs. [ABSTRACT FROM AUTHOR]

Highlights: The fundamental properties of electric dipoles and their specific roles in perovskite solar cells are discussed. Research progress of interfacial dipoles in perovskite solar cells is summarized. Challenges of deterministic characterization of electric dipoles and future perspectives are highlighted. Design and modification of interfaces have been the main strategies in developing perovskite solar cells (PSCs). Among the interfacial treatments, dipole molecules have emerged as a practical approach to improve the efficiency and stability of PSCs due to their unique and versatile abilities to control the interfacial properties. Despite extensive applications in conventional semiconductors, working principles and design of interfacial dipoles in the performance/stability enhancement of PSCs are lacking an insightful elucidation. In this review, we first discuss the fundamental properties of electric dipoles and the specific roles of interfacial dipoles in PSCs. Then we systematically summarize the recent progress of dipole materials in several key interfaces to achieve efficient and stable PSCs. In addition to such discussions, we also dive into reliable analytical techniques to support the characterization of interfacial dipoles in PSCs. Finally, we highlight future directions and potential avenues for research in the development of dipolar materials through tailored molecular designs. Our review sheds light on the importance of continued efforts in this exciting emerging field, which holds great potential for the development of high-performance and stable PSCs as commercially demanded. [ABSTRACT FROM AUTHOR]

The photovoltaic (PV) performance of perovskite solar cells (PSCs) has rapidly advanced in the recent years; yet, the stability issue remains one of the last‐mile challenges on the road to commercialization. Charge transport layers and their interfaces with perovskites stand for critical tuning knobs that determine the device stability of PSCs. This review focuses on the effects of modification of SnO2 electron transport layers (ETLs) on the interfacial physicochemical properties and stability of PSC devices. In detail, the intrinsic defects, surface hydroxyls, and nonuniform morphology of SnO2 will negatively impact its interfacial physicochemical properties, thus degrading the device stability of PSCs. To tackle these existing issues, three modification approaches, such as surface morphology control, surface physicochemical modifications, and surface composite‐structure design, are categorized. Lastly, future perspectives in further promoting the stability of PSCs from SnO2 ETLs are raised based on the currently unresolved issues from both material and device levels. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s40820-023-01131-4.Correction to: Nano-Micro Lett. (2023) 15:173https://doi.org/10.1007/s40820-023-01131-4.In the version of this Article originally published online, there was an error in the schematics of Figures 2b and 2c. These errors have now been corrected in the original article.GraphOriginal and corrected of Figures 2b and 2c.By Yinyi Ma; Jue Gong; Peng Zeng and Mingzhen LiuReported by Author; Author; Author; Author [Extracted from the article]

Layered halide perovskites (LHPs) with crystallographically 2D structures have gained increasing interest for photovoltaic applications due to their superior chemical stability and intriguing anisotropic properties, which are in contrast to their conventional 3D perovskite counterparts. The most frequently studied LHPs are Ruddlesden–Popper (RP) phases, which suffer from a carrier‐transport bottleneck due to the van der Waals gap associated with their intrinsic organic interlayer structures. To address this issue, Dion–Jacobson (DJ) and alternating‐cation‐interlayer (ACI) LHPs have rapidly emerged, which exhibit unique structural and (opto)electronic characteristics that may resemble those of the 3D counterparts owing to the eliminated or reduced van der Waals gap. Improved photophysical properties have been achieved in DJ and ACI LHPs, leading towards better photovoltaic performance. Here we provide a comprehensive discussion on the merits and promises of DJ and ACI LHPs from a chemistry perspective. Then, we review recent progress on the synthesis and tailoring of DJ and ACI LHP crystals and thin films, as well as their optoelectronic properties and photovoltaic performance. Finally, we discuss possible pathways to overcome critical challenges to realize the full potential of DJ and ACI LHPs for high‐performance solar cells and beyond. [ABSTRACT FROM AUTHOR]

The soft nature of organic–inorganic halide perovskites renders their lattice particularly tunable to external stimuli such as pressure, undoubtedly offering an effective way to modify their structure for extraordinary optoelectronic properties. Here, using the methylammonium lead iodide as a representative exploratory platform, it is observed that the pressure‐driven lattice disorder can be significantly suppressed via hydrogen isotope effect, which is crucial for better optical and mechanical properties previously unattainable. By a comprehensive in situ neutron/synchrotron‐based analysis and optical characterizations, a remarkable photoluminescence (PL) enhancement by threefold is convinced in deuterated CD3ND3PbI3, which also shows much greater structural robustness with retainable PL after high peak‐pressure compression–decompression cycle. With the first‐principles calculations, an atomic level understanding of the strong correlation among the organic sublattice and lead iodide octahedral framework and structural photonics is proposed, where the less dynamic CD3ND3+ cations are vital to maintain the long‐range crystalline order through steric and Coulombic interactions. These results also show that CD3ND3PbI3‐based solar cell has comparable photovoltaic performance as CH3NH3PbI3‐based device but exhibits considerably slower degradation behavior, thus representing a paradigm by suggesting isotope‐functionalized perovskite materials for better materials‐by‐design and more stable photovoltaic application. [ABSTRACT FROM AUTHOR]

p–p orbital interaction through Mg(II) isovalent doping in methylammonium lead chloride perovskite significantly enhances the electronic properties while not affecting the optical bandgap. This chemical behaviour shows promising applications to optoelectronic devices. [ABSTRACT FROM AUTHOR]

State-of-the-art halide perovskite solar cells have bandgaps larger than 1.45 eV, which restricts their potential for realizing the Shockley-Queisser limit. Previous search for low-bandgap (1.2 to 1.4 eV) halide perovskites has resulted in several candidates, but all are hybrid organic-inorganic compositions, raising potential concern regarding device stability. Here we show the promise of an inorganic low-bandgap (1.38 eV) CsPb0.6Sn0.4I3 perovskite stabilized via interface functionalization. Device efficiency up to 13.37% is demonstrated. The device shows high operational stability under one-sun-intensity illumination, with T80 and T70 lifetimes of 653 h and 1045 h, respectively (T80 and T70 represent efficiency decays to 80% and 70% of the initial value, respectively), and long-term shelf stability under nitrogen atmosphere. Controlled exposure of the device to ambient atmosphere during a long-term (1000 h) test does not degrade the efficiency. These findings point to a promising direction for achieving low-bandgap perovskite solar cells with high stability. Current research focus on the perovskites solar cells (PSCs) is mainly limited to the lead-based ones with bandgaps above 1.5 eV. Here Hu et al. report efficient and stable inorganic tin-containing PSCs, opening doors to exploring abundant perovskite materials with bandgaps lower than 1.4 eV. [ABSTRACT FROM AUTHOR]

Bond length and bond angle exhibited by valence electrons is essential to the core of chemistry. Using lead-based organic-inorganic perovskite compounds as an exploratory platform, it is demonstrated that the modulation of valence electrons by compression can lead to discovery of new properties of known compounds. Yet, despite its unprecedented progress, further efficiency boost of lead-based organic-inorganic perovskite solar cells is hampered by their wider bandgap than the optimum value according to the Shockley-Queisser limit. By modulating the valence electron wavefunction with modest hydraulic pressure up to 2.1 GPa, the optimized bandgap for single-junction solar cells in lead-based perovskites, for the first time, is achieved by narrowing the bandgap of formamidinium lead triiodide (HC(NH2)2PbI3) from 1.489 to 1.337 eV. Strikingly, such bandgap narrowing is partially retained after the release of pressure to ambient, and the bandgap narrowing is also accompanied with double-prolonged carrier lifetime. With First-principles simulation, this work opens a new dimension in basic chemical understanding of structural photonics and electronics and paves an alternative pathway toward better photovoltaic materials-by-design. [ABSTRACT FROM AUTHOR]

Two pseudohalide thiocyanate ions (SCN−) have been used to replace two iodides in CH3NH3PbI3, and the resulting perovskite material was used as the active material in solar cells. In accelerated stability tests, the CH3NH3Pb(SCN)2I perovskite films were shown to be superior to the conventional CH3NH3PbI3 films as no significant degradation was observed after the film had been exposed to air with a relative humidity of 95 % for over four hours, whereas CH3NH3PbI3 films degraded in less than 1.5 hours. Solar cells based on CH3NH3Pb(SCN)2I thin films exhibited an efficiency of 8.3 %, which is comparable to that of CH3NH3PbI3 based cells fabricated in the same way. [ABSTRACT FROM AUTHOR]

Halide Perovskites: Suppressed Lattice Disorder for Large Emission Enhancement and Structural Robustness in Hybrid Lead Iodide Perovskite Discovered by High-Pressure Isotope Effect (Adv. Funct. Perovskite, high-pressure, bandgap, mechanical and optical properties, stability Keywords: perovskite; high-pressure; bandgap; mechanical and optical properties; stability EN perovskite high-pressure bandgap mechanical and optical properties stability 1 1 1 02/26/21 20210224 NES 210224 In article number 2009131, Gang Liu and co-workers conduct high-pressure isotope research to discover a significantly suppressed lattice disorder realized by H/D substitution in hybrid halide perovskites, which reveals large emission enhancement and strong structural robustness in isotope-functionalized perovskite materials. [Extracted from the article]