Hongwei Song

Perovskite solar cells (PSCs) offer strong potential for sustainable energy conversion, yet their reliance on toxic‐lead (Pb) continues to restrict environmental compatibility and large‐scale deployment. To address this challenge, a dual‐interface Pb‐management approach enabled by custom‐designed chelating molecules is introduced. These tailored chelators are engineered with high Pb ²⁺ affinity and controlled coordination geometry, allowing them to suppress Pb‐related defect formation, promote vertical grain growth, and release residual lattice stress. When synergistically forming an internal encapsulation layer on both sides of the perovskite film with chitosan (CS), it supports efficient charge transport and enhances structural integrity. This configuration reduces Pb leakage to 0.86 ppm after 9 h immersion in pure water, which is below wastewater discharge limits, and efficiently mitigates Pb‐induced biotoxicity. Adopting this strategy p‐i‐n devices maintain 96% of initial performance after 3000 h of exposure and reach a champion efficiency of 26.91% (third‐party certified efficiency 26.60%). The unverified efficiency of n‐i‐p devices reached 25.60%. The strategy is applicable to both p‐i‐n and n‐i‐p device architectures and may be extendable to other Pb‐based perovskite systems.

Ytterbium-ion (Yb3+)-doped quasi-2D layered metal halide perovskites (quasi-2D LMHPs) stand out as a transformative platform for near-infrared (NIR) emissions beyond 950 nm, holding great promise for revolutionizing next-generation photonic systems. Herein, we report a synergistic engineering strategy to simultaneously regulate phase distribution in the emissive layer and carrier transport in the hole-transport layer, enabling record-performance NIR perovskite light-emitting diodes (PeLEDs) emitting at 986 nm. The incorporation of fluorinated aromatic spacers (p-F-PEA+) and partial formamidinium (FA+) substitution strengthens organic–inorganic interactions, affording well-controlled phase distribution and highly efficient exciton-to-Yb3+ energy transfer. Meanwhile, zwitterionic kanamycin is introduced to neutralize the intrinsic acidity of PEDOT:PSS via distinct chemical interactions, leading to balanced carrier injection and suppressed nonradiative recombination. Benefiting from this dual-layer modulation, the optimized Yb3+-doped (PEA1.8p-F-PEA0.2)(Cs1.6FA0.4)Pb3Br10 PeLEDs exhibit a record peak NIR external quantum efficiency (EQE) of 12.1% at 986 nm and an outstanding operational half-life (T50) of 1823 min. More critically, we break the scalability bottleneck of NIR PeLEDs with 300 mm2 large-area devices delivering a state-of-the-art EQE of over 7.5%. We pioneer a visible/NIR dual-mode display and imaging platform via patterned PeLEDs, integrating explicit visible identification and covert NIR high-security anticounterfeiting. This work broadens the application prospects of NIR PeLEDs in high-security anticounterfeiting, nondestructive imaging, and smart photonic systems.

The realization of efficient 1.54 µm electroluminescence from erbium ions is persistently hampered by their intrinsically small absorption cross-section and low excitation efficiency in conventional hosts. This study addresses this by synthesizing lead-free Cs₃CrBr₆ perovskite nanocrystals. This material is a direct-bandgap n-type chromium-based halide semiconductor whose electronic structure provides good charge transport, serving as a suitable host for lanthanide doping. Er³⁺ incorporation serves as an efficient luminescent center and modulates the host’s band structure. Leveraging the broadband absorption of Cr³⁺ for sensitization, combined with surface passivation, we achieve highly efficient Cr³⁺ to Er³⁺ energy transfer. This yields intense 1.54 µm emission with a photoluminescence quantum yield of 47%. The corresponding electroluminescent device attains a peak external quantum efficiency of 3.26%, among the highest values reported for solution-processed, Er³⁺-based near-infrared light-emitting diodes. This performance robustly validates the host’s effectiveness in facilitating charge injection and transport. Consequently, this work provides a viable material strategy for high-performance 1.54 µm emission and lays a solid foundation for chromium-based halide perovskites in advanced optoelectronics.

Lead‐free rare‐earth‐based halide perovskite have emerged as a promising candidate for near‐infrared light‐emitting diodes (NIR‐LED), yet their development has been hindered by inefficient energy transfer and severe non‐radiative losses. Here, we report a comprehensive optimization strategy for Cs ₃ YbBr ₆ :Er ³⁺ nanocrystals through Sb ³⁺ sensitization and niacin passivation, achieving record‐breaking electroluminescence performance. Systematic investigations reveal that Yb ³⁺ serves as a critical energy transfer bridge, with optimal 5% Er ³⁺ doping yielding a PLQY of 20.34% at 1540 nm. The introduction of Sb ³⁺ as an efficient sensitizer captures free exciton and enhances energy transfer, boosting the 1540 nm PLQY to 36.6%. First‐principles calculations demonstrate that Sb ³⁺ incorporation reduces the bandgap and promotes charge localization around [SbBr ₆ ] ³⁻ octahedra. Furthermore, niacin molecules selectively passivate undercoordinated Yb ³⁺ sites via carboxyl coordination, reducing film roughness, decreasing trap densities, and achieving balanced carrier mobilities. The resulting LED exhibits multi‐wavelength emissions, peaking at 470 nm, 980 and 1540 nm, respectively. It demonstrates an external quantum efficiency of 9.96% and exceptional operational stability of 753 min (T ₅₀ ), representing the highest efficiency reported for various rare‐earth‐based perovskite LEDs. A practical infrared imaging system is successfully demonstrated, highlighting the potential of this materials platform for next‐generation optoelectronic applications.

Near-infrared (NIR) electroluminescence at 1.54 μm is vital for optical communication and bioimaging. Although CsPbCl3:Yb3+, Er3+ perovskite quantum dots (PQDs) represent a promising emitter platform, their device efficiency is hindered by intrinsically weak Er3+ emission. Here, we achieve highly efficient 1.54 μm electroluminescence via a bulk-surface dual-reconstruction strategy. Within the lattice interior, Na+ incorporation fills Pb vacancies and perturbs local crystal-field symmetry, suppressing non-radiative decay while enhancing the Er3+ and Yb3+ radiative transition rates by 7.83-fold and 3.30-fold, respectively. This boosts the Yb3+-to-Er3+ energy transfer efficiency from 15% to 56.6%. Concurrently, at the PQD surface, passivation with trifluoromethanesulfonate (OTF-) eliminates halogen vacancies via robust Lewis acid--base coordination, yielding a 45% photoluminescence quantum yield (PLQYs) at 1.54 μm. Consequently, the optimized NIR perovskite light-emitting diodes deliver a 3.27% external quantum efficiency, a 2.03 mW sr–1 cm–2 peak radiance, and an operational half-life exceeding 120 min.

High-quality perovskite films are essential to device efficiency and stability, yet inhomogeneous crystallization and interfacial defects remain major challenges. Here, we introduce a vapor-phase annealing (VPA) strategy to regulate crystallization kinetics and film morphology. By establishing a uniform thermal-humidity field, VPA is proposed to promote a bottom-up crystallization tendency, in contrast to the conventional top-down mode often observed in hot-plate annealing. This shift in growth direction could facilitate homogeneous nucleation, reduce interfacial void formation, and enable more complete precursor conversion with suppressed PbI₂ residue. As a result, the films exhibit improved optoelectronic properties, and additive-free inverted perovskite solar cells achieve a champion power conversion efficiency (PCE) of 22.15% with excellent long-term stability. These results suggest that VPA may provide a scalable route to mitigating crystallization inhomogeneity in perovskite photovoltaics.

The exponential demand for energy-efficient and adaptive computing architectures drives the evolution of artificial intelligence (AI) and machine learning (ML). Neuromorphic computing, inspired by biological neural networks, overcomes the limitations of traditional von Neumann architectures, including high energy consumption and limited scalability. The introduction of two-dimensional (2D) materials, such as transition metal dichalcogenides, hexagonal boron nitride, black phosphorus, and tellurene, enables neuromorphic devices with unprecedented control over electronic and optoelectronic properties. These materials exhibit atomic-scale thickness, high carrier mobility, and tunable bandgaps, facilitating synaptic behaviours such as spike-timing-dependent plasticity and paired-pulse facilitation. This review describes the integration of 2D materials into neuromorphic systems, highlighting applications in wearable electronics, brain–machine interfaces, and quantum neuromorphic platforms. In wearable and edge computing, 2D-based devices enable localized, ultra-low-power data processing. In brain–machine interfaces, they enhance signal transduction and neural interfacing. Quantum effects in 2D materials further enable hybrid quantum–classical neuromorphic architectures for high-dimensional computational tasks. Despite significant advances, challenges in reproducibility, scalability, and stability remain. Addressing these limitations through innovations in synthesis and defect passivation is essential for practical application. This review underscores the transformative potential of 2D-material-based neuromorphic computing for energy-efficient AI.

Tin dioxide (SnO ₂ ) is widely used as the electron transport layer (ETL) in n‐i‐p type perovskite solar cells (PSCs), yet its practical potential is plagued by intrinsic oxygen vacancies and structural defects arising from chemical bath deposition (CBD). Herein, we propose a facile pretreatment strategy: integrating water‐soluble terbium oxide nanocrystalline (Tb ₂ O ₃ NCs) into the CBD‐derived SnO ₂ ETLs post‐cleaning but pre‐annealing. Systematic characterizations confirm that Tb ₂ O ₃ NCs induce a homogeneous SnO ₂ ‐Tb ₂ O ₃ composite interface via lattice oxygen‐mediated interfacial interaction. The abundant lattice oxygen of Tb ₂ O ₃ NCs mediates the passivation of SnO ₂ oxygen vacancies by replenishing oxygen defects. Meanwhile, the lattice oxygen‐regulated composite ETL exhibits enhanced carrier mobility, reduced surface roughness, and optimized surface energy, which synergistically promote perovskite crystallization into large‐grain films with superior light‐trapping capability. Consequently, the target PSCs achieve a champion power conversion efficiency (PCE) of 25.95%. Furthermore, the lattice oxygen‐mediated interfacial bonding mitigates ETL tensile strain under thermal cycling. These synergistic merits significantly enhance the device's humidity stability and operational stability in ambient air. This work provides a facile and scalable strategy to simultaneously engineer the defect state and structural integrity of SnO ₂ ETLs, offering valuable insights for the rational design of high‐efficiency and stable PSCs.

Er ³⁺ ‐doped 1540 nm light‐emitting diodes (LEDs) are critical components in optical communications C‐band, non‐trunk communication, bioimaging, and sensing. However, integrating high luminous efficiency with tailored circularly polarized luminescence (CPL) in such LEDs remains a critical challenge. Here, we demonstrate efficient 1540 nm short‐wave infrared (SWIR) electroluminescence with distinct CPL in Cs ₃ ErCl ₆ nanocrystals (NCs)‐based LEDs via a synergistic strategy of Sb ³⁺ /Y ³⁺ co‐doping and camphor ligand modification. Y ³⁺ doping modulates lattice symmetry, inducing Stark splitting of the Er ³⁺ energy level and enhancing luminescence intensity. Sb ³⁺ introduction triggers efficient self‐trapped excitons emission at 530 nm, whose energy levels match Er ³⁺ states to boost energy transfer efficiency. Subsequently, camphor ligand exchange passivates Er ³⁺ ‐related defects, increasing the 1540 nm photoluminescence quantum yield to 35.7% and endowing NCs with CPL (asymmetry factor: −3.67 × 10 ⁻² ) via camphor's chiral structure. SWIR LEDs based on camphor‐modified Cs ₃ Er _0.7 Y _0.3 Cl ₆ : Sb ³⁺ NCs exhibit a record‐high external quantum efficiency of 3.06% at 1540 nm, and first, demonstrate electrically‐driven circularly polarized 1540 nm emission with asymmetry factor of −3.08 × 10 ⁻² . This work presents a synergistic doping‐ligand strategy for Er‐based halide optoelectronics, offering a versatile platform to develop high‐performance long‐wavelength devices with integrated efficient emission and tailored polarization, crucial for advancing next‐generation optical communication and bioimaging.

The performance of single‐electrode triboelectric nanogenerators (SE‐TENGs) is governed by the effective contact area and dielectric properties. Synergistically optimizing both within a sustainable design remains challenging. Herein, a recyclable SE‐TENG is presented through the synergistic integration of a pseudo‐honeycomb microstructure and liquid metal (LM) doping. The template‐assisted electrospun microstructure significantly enhances the contact area for efficient charge generation, while the dispersed LM nanoparticles significantly enhance the dielectric properties for superior charge trapping and transport. This approach enhances the open‐circuit voltage by 120% (from 70.8 to 156 V) and achieves a power density of 122 mW m ⁻² . Furthermore, the use of a recyclable polymer matrix enables a closed‐loop recycling pathway, with the device retaining over 90% of its initial output after seven cycles. Its practical utility is demonstrated through programmable wireless switching, time‐verifiable access control, and assistive monitoring for speech‐impaired users in a self‐powered smart home system. This work provides a foundational design paradigm for customizable, high‐performance, and sustainable electronics.