Liya Zhou

Hole transport layer‐free carbon‐based perovskite solar cells (HTL‐free C‐PSCs) suffer rapid performance decay under operational stressors, driven by iodine migration and photogenerated superoxide radicals (O ₂ ^•− ). To break this photo‐oxidation‐iodine migration vicious cycle, we design a multifunctional molecular stabilizer, tetrakis(4‐carboxyphenyl)tetrathiafulvalene (4B‐TTF). This tailor‐made “molecular guard” works via two synergistic mechanisms: its reversible TTF core acts as a charge‐transfer mediator, reducing I ₂ to I ⁻ and scavenging O ₂ ^•− , while four peripheral benzoic acid groups anchor to undercoordinated Pb ²⁺ sites, passivating grain‐boundary defects. Incorporating 4B‐TTF into MAPbI ₃ ‐based devices yields a champion power‐conversion efficiency (PCE) of 19.96%, vs. 17.58% for the control, by suppressing non‐radiative recombination. Unencapsulated devices retain 96.4% of their initial efficiency after 1200 h under ambient storage and 93.5% after 120 h under harsh UV‐oxygen exposure; encapsulated devices retain 90.32% after 700 h of continuous maximum power point (MPP) tracking under 1‐sun illumination at 55°C in nitrogen. The strategy is further validated in Cs _0.17 FA _0.83 PbI ₃ systems, delivering a state‐of‐the‐art PCE of 20.70%. This work provides a unified molecular‐level strategy to concurrently address ionic, radical, and defect‐related degradation, bridging the performance gap between low‐cost HTL‐free devices and conventional high‐cost architectures.

Electrochemical CO ₂ reduction reaction (CO ₂ RR) to CH ₄ offers a sustainable route for carbon neutrality, but it is hindered by sluggish multi‐electron/proton transfer kinetics and poor selectivity. Herein, we rationally design an oxygen‐rich Cu‐CeO ₂ catalyst by constructing a heterointerface built‐in electric field (BIEF) for efficient and selective CO ₂ ‐to‐CH ₄ conversion. The abundant oxygen vacancies induce intense charge redistribution and amplify the directional BIEF driving electron transfer from CeO ₂ to Cu, which strengthens CO ₂ adsorption, stabilizes *CO intermediates, and lowers the energy barrier of *CO‐to‐*CHO conversion. The optimized Cu/CeO ₂ ‐900 catalyst exhibits outstanding CO ₂ RR performance, delivering a maximum CH ₄ Faradaic efficiency of 73.7% and a large CH ₄ partial current density of −307.33 mA cm ⁻² , together with excellent durability over long‐term continuous operation. A combination of in situ spectroscopic characterizations, electrochemical measurements, and density functional theory calculations validates the oxygen vacancy‐amplified BIEF mechanism and its critical role in boosting CO ₂ activation and reaction kinetics. This work establishes a novel defect‐BIEF synergistic strategy to regulate interfacial charge transfer and intermediate adsorption, offering a universal guideline for designing high‐performance electrocatalysts toward selective CO ₂ conversion to CH ₄ .

Electrochemical CO2 reduction reaction (CO2RR) to CH4 represents a promising pathway toward carbon neutrality, yet it is severely limited by sluggish multi-electron/proton transfer kinetics, low selectivity, and insufficient proton supply. Herein, we rationally fabricated a series of Cu-doped Er2O3 catalysts (Cu-Er2O3-x) via sequential precipitation and calcination, which engineer a strong built-in electric field (BIEF) for efficient and selective CO2-to-CH4 conversion. Cu doping triggers significant charge redistribution between Cu and Er2O3, forming positively charged Cu sites and a negatively polarized Er2O3 matrix. The generated BIEF reorients interfacial water into an H-near configuration, shortens the *H–catalyst distance, promotes water dissociation, and optimizes *CHO adsorption. The optimal Cu-Er2O3-6 catalyst achieves a high CH4 Faradaic efficiency of 60.79% and a large CH4 partial current density of −28.01 mA·cm−2 at −1.6 V vs. reversible hydrogen electrode (RHE) in an H-type cell, with an outstanding stability of 24 h. In situ attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS), electrochemical tests, and density functional theory (DFT) calculations reveal that BIEF-modulated water orientation and electronic optimization accelerate proton transfer and lower the energy barrier of the rate-determining *CHO → *CH2O step. This work provides a robust strategy for boosting CO2RR performance via BIEF engineering and *H–catalyst distance regulation, offering a valuable design principle for advanced CH4-selective electrocatalysts.

The rational design of chiral ligands for perovskite quantum dots (PQDs) and the understanding of their structure-property relationships is challenging. Herein, l/d-proline (l/d-Pro) induces a concentration-dependent coordination transition from monofunctional to bidentate mode, enabling defect passivation and chiral transfer. green chiral PQDs achieve 99.69% photoluminescence quantum yield (PLQY) and emission dissymmetry factor (g_lum) of -2.1 × 10^-3. A light-mediated halide exchange strategy enables full-visible (440-760 nm) emission tuning, enhancing |g_lum| to 7.1 × 10^-3 while maintaining high blue/red PLQYs (88.96%/91.42%) via enhanced octahedral distortion. High-performance full-color circularly polarized light-emitting diodes (CP-LEDs) and white LEDs are fabricated, providing a paradigm for chiral perovskite optoelectronic device design.

The denser asymmetric hydrogen-bonding network of chiral ( R )-α-Mn isomer greatly distorts [MnBr ₄ ] ²⁻ tetrahedra, resulting in a superior SHG-CD response compared to that of ( R )-β-Mn isomer.

Intrinsically chiral active optical materials are currently a subject of intense research. While chiral ligand modification is an effective strategy for imparting chirality to perovskite quantum dots (PQDs), it faces challenges related to a limited luminescence dissymmetry factor and stability. Herein, this work reports a one-pot synthesis of R-/S-CsPbBr₃@SiO₂ PQDs. The chiral characteristics of R-/S-CsPbBr₃@SiO₂ PQDs originate from the surface anchoring of R-/S-2-phenylglycinol (R-/S-Phe), which triggers chiral lattice distortion of the [PbBr₆]^4- octahedra and strong electronic coupling. Notably, the silica shell acts not just as a protective barrier but as a spatial confinement matrix that facilitates a higher density of chiral ligand loading, thereby amplifying the dissymmetry factor (g_lum = -1.14 × 10^-2) by nearly an order of magnitude compared to bare counterparts. The encapsulated PQDs simultaneously achieve a high photoluminescence quantum yield of 84 ± 1%, exceptional water stability, and intense circularly polarized luminescence. This work offers a strategy for enhancing the chiroptical signals in multifunctional chiral metal halides.

A processing window exists during the transition between film formation and the annealing step in the two-step method employed for the fabrication of FAPbI₃ perovskite solar cells, independent of whether the aim is to produce a batch of small-area or large-area devices. A significant variance in the power conversion efficiencies of perovskite devices, resulting from different processing windows, leads to a marked decrease in device reproducibility. To investigate the changes occurring within the perovskite wet film during the processing window, this study utilized nitrogen protection packaging technology to monitor the crystallization process of the perovskite wet film outside the glove box. The observation indicated non-uniform intermediate-phase reaction rates. The incorporation of 3-cyanopyridine into the two-step method decelerated the crystallization kinetics of the perovskite wet film, suppressing the formation of δ-FAPbI₃. Such modification expanded the processing window time, enabling the preparation of perovskite films with superior crystallinity and minimal defects. The n-i-p type perovskite solar cells exhibited a power conversion efficiency (PCE) of 25.12%. The findings demonstrate that this modification method effectively extends the processing window time of the two-step method, leading to the fabrication of perovskite devices with optimal performance and high repeatability. This represents a novel strategy for the batch production of perovskite devices and the manufacturing of large-area perovskite films.