The development of highly efficient blue emitters capable of effectively harvesting triplet excitons remains a major challenge in organic light emitting diodes (OLEDs) research. Emitters featuring hybridized local and charge-transfer (HLCT) excited states have demonstrated considerable potential for facilitating rapid high-lying triplet reverse intersystem crossing. Herein, two molecules, TRZ-p-12SIDCz and TRZ-Bp-IDCz, were synthesized by modulating the donor conjugation length to regulate their excited-state properties. Theoretical calculation and experimental results showed that they have HLCT characteristics, excellent thermal properties, and different emission colors. OLEDs devices doped with TRZ-p-12SIDCz and TRZ-Bp-IDCz achieved excellent efficiency with the the Commission internationale de l'eclairage (CIE) coordinate are (0.160, 0.126) and (0.251, 0.370) and the maximum external quantum efficiencies (EQEmax) of 0.74% and 2.85%, respectively. This study confirms that optimizing the hRISC channel of HLCT emitters by modulating the conjugation of electron donors is feasible.

The development of efficient and spectrally stable sky-blue metal-halide perovskite light-emitting diodes (PeLEDs) remains a substantial challenge, primarily due to high-density defect states and halide ion migration in mixed-halide quasi-2D perovskite systems. Here, we introduce an amphiphilic zwitterionic molecule, sulfobetaine 10 (SFB10), as a multifunctional additive to address these limitations in bromine/chlorine mixed quasi-2D perovskite films. SFB10 enables simultaneous defect passivation and structural stabilization through its complementary functional groups: the sulfonate and quaternary ammonium moieties effectively passivate uncoordinated Pb2+ ions and cesium vacancies, respectively, while the hydrophobic alkyl chains form a protective layer that enhances environmental stability and suppresses halide migration. This synergistic effect significantly improves the optoelectronic properties of the perovskite films, yielding a notable increase in photoluminescence intensity, an extended fluorescence lifetime, and optimized crystalline morphology with dense, smooth surfaces. As a result, the fabricated sky-blue PeLEDs (emitting at 485 nm) achieve a significantly improved external quantum efficiency of 2.65% (nearly 70% improvement) and luminance of 1651.1 cd/m2, together with exceptional spectral stability under high electric fields. This work highlights the promise of molecularly designed zwitterionic additives in enabling high-performance and operationally stable perovskite optoelectronic devices.

Neuromorphic computing continues to advance, fueling the pursuit of enhanced information processing and learning capabilities. This study introduces a novel photonic synaptic transistor (PST) based on crystallized conjugated polymers. Engineered to efficiently respond to standard temporal signals and digital images, this PST mimics the human retina's in-sensor computing mechanism. Developed through low-temperature solvent engineering, the PST optimizes charge carrier mobility and light absorption by finely tuning the polymer's microstructure. In a groundbreaking application, this PST has been used for image classification and Morse code recognition within reservoir computing frameworks. The polymer's microstructure modulation notably enhances the device's short-term and long-term plasticity, synaptic weight update efficiency, and training and recognition accuracy. These advancements underscore the potential of crystallized conjugated polymer-based PSTs to revolutionize next-generation neuromorphic computing systems. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

The significant challenges in lithium recovery from salt lake via solvent extraction is the moderate lithium selectivity and the dissolution loss of extractants in aqueous phase. In order to tackle these challenges for lithium extraction for the real application, in this work, quantum chemistry calculation was employed to quantify the steric hindrance of neutral phosphate extractants with both aromatic and alkyl substituents. Among the candidates, 2-ethylhexyl diphenyl phosphate (EHDP) was identified as the most promising extractant and was further validated through extraction experiments. A novel extraction system, EHDP-MIBK-FeCl3, was proposed and systematically optimized. Under the optimal extraction conditions, EHDP exhibited the highest steric hindrance and the lowest dissolution loss. Up to 91% lithium extraction was achieved at a single-stage, with negligible magnesium co-extraction. The mechanism was elucidated using FT-IR, UV-vis, Raman, NMR, and electrospray ionization mass spectrometry (ESI-MS). The extracted lithium species were confirmed to include [Li center dot 2EHDP]+, [Li center dot 3EHDP]+, and [Li center dot 2EHDP center dot 2H2O]+. Finally, the system was applied to real brine from the Qarhan Salt Lake. The extraction efficiency of lithium ELi can reach 83% at single stage and the separation factor of lithium and magnesium beta Li/Mg reaches 106,824, demonstrating excellent selectivity and promising industrial applicability.

With the rapid development of lithium batteries, energy storage and controlled nuclear fusion, the demand for lithium is increasing rapidly. Direct lithium extraction from unconventional brines (e.g., oilfield brines) is becoming increasingly critical. However, unlike traditional high Mg/Li salt lake brines, these systems typically contain high concentrations of calcium ions, which further increases the difficulty of lithium separation. To address these challenges, this study proposes two novel extraction systems that enable direct lithium extraction from brines with high concentrations of magnesium, calcium and sodium through a stepwise process. First, a triphenyl phosphate-tetraphenylborate synergistic system achieves 84% lithium recovery from simulated raw brine. By employing a strategy combining lithium stripping with in-situ precipitation of magnesium and calcium ions, the separation factors for Li/Mg and Li/Ca reach 178 and 1528, respectively. Single crystal structure analysis reveals the separation mechanism of lithium from magnesium and calcium by the organophosphorus extractant at the molecular level for the first time, and mass spectrometry analysis verifies the selective migration behavior of lithium ions during the extraction process. The resulting alkaline lithium solution is further treated with a novel diketone system, achieving a single-stage lithium extraction efficiency of 89% and a Li/Na separation factor of 415. The two-step strategy achieves an overall lithium recovery of 80% from raw brine, significantly higher than the conventional process. The obtained lithium carbonate is confirmed as battery-grade by XRD and composition analysis. This work provides molecular insights for designing novel lithium extractants and offers a new approach for direct lithium extraction from raw brines.

Through-space charge transfer (TSCT) thermally activated delayed fluorescence (TADF) emitters typically exhibit relatively low radiative decay rate (k(r)(s)), which remains a formidable obstacle to further improving device efficiency and suppressing efficiency roll-off. Here, two novel deep-blue TSCT-TADF emitters (YCIT14 and YCIT15) were rationally developed. Both emitters feature 2,4-diphenyl-1,3,5-triazine (DPTRz) and 2,4,6-triphenyl-1,3,5-triazine (TPTRz) as acceptor (A) units, which are interconnected via a phenyl bridging structure with 9-phenyl-9H-carbazole (9-PhCz) donor (D) group. Through precise structural modulation, YCIT15 incorporates an extra phenyl spacer unit compared to YCIT14, establishing a well-defined V-shaped conformation that enforces intimate face-to-face alignment between the donor and acceptor moieties. This distinct spatial configuration significantly amplifies intramolecular D-A electronic coupling through enhanced orbital overlap. These interactions enable not only through-bond charge transfer (TBCT) but also TSCT between the D and A fragments. As a consequence, YCIT15 achieves a small singlet-triplet energy gap (Delta E-ST) and high efficiency. Both molecules exhibit TSCT and TBCT characteristics, accompanied by rapid reverse intersystem crossing rates (k(RISC) >10(5) s(-1)) and high radiative decay rate (k(r)(s) >10(7) s(-1)) in neat films. The doped organic light-emitting diodes (OLEDs) utilizing YCIT14 and YCIT15 as emitters show deep-blue electroluminescence (EL), with emission peaks at 448 nm and 428 nm, respectively.

Bioinspired reconfigurable photodetectors (PD) promise to address complex image processing challenges, yet existing devices are often hindered by complex fabrication and rigid formats. Here, we present an ultraflexible, paper-based perovskite photodetector fabricated via a simple one-pot approach. The device leverages UV-assisted ion redistribution at perovskite/cellulose interfaces to achieve multimode bidirectionally tunable photoresponsivity (from -51.7 to +52.5 mu A/W at zero bias under 520 nm illumination) with high linearity. It exhibits exceptional mechanical robustness, maintaining stable performance after 10,000 bending cycles at a 5 mm radius. Leveraging this reconfigurability, we demonstrate in-sensor image preprocessing (including grayscale inversion, smoothing, and sharpening) and achieve up to 98% classification accuracy for blurred patterns. This work provides a low-cost, biodegradable platform for intelligent vision systems in wearable and biointegrated electronics.

To achieve efficient and selective extraction of cesium (Cs+) from complex salt-lake brines, this study developed a dual-network hydrogel adsorbent based on ammonium thiostannate (NTS), denoted as NTS@(SA+PAA)-1.0. The dual-network hydrogel, composed of sodium alginate (SA) and poly(acrylic acid) (PAA), serves as a stable support for the NTS powder, endowing the adsorbent with favorable mechanical robustness and high salt tolerance. Static adsorption experiments revealed that the composite adsorbent retains the excellent Cs+ selectivity inherent to the pristine NTS powder. In the presence of competing ions (e.g., Na+ and Mg2+), the distribution coefficient K-d(Cs) exceeds 10(4) mL/g. Dynamic column adsorption experiments further confirmed the material's significant Cs+ enrichment capability in real brines. A single adsorption-desorption cycle resulted in a nearly 13-fold increase in the Cs+ concentration and an approximately 72-fold increase in the mass fraction. After five consecutive cycles, the material maintained structural stability and sustained its adsorption performance. This study provides a novel composite gel adsorbent with practical application potential for the efficient and continuous extraction of cesium from brine.

Synergistic liquid-liquid extraction (LLE) of Li+ commonly relies on β-diketonates in combination with neutral phosphine oxides such as tri-n-octylphosphine oxide (TOPO), yet the co-ligand is typically treated as an empirical additive rather than a design element. Here we show that commercially available diphosphine dioxides, featuring a preorganised PO⋯PO donor set and a spacer-defined bite, act as powerful co-ligands for Li+ extraction with 3-benzoyl-1,1,1-trifluoroacetone (HBTA) under mild pH conditions. Compared to TOPO, the best-performing PO⋯PO co-ligand enhances Li+ transfer while suppressing Na+/K+ co-extraction, consistent with altered solution speciation and stoichiometry. These results establish a chelating co-ligand (PO⋯PO) as a simple, modular strategy to control synergy in Li+ extraction systems based on classical CO⋯CO extractants such as HBTA.

The increasing application of hydrochar (HC) for soil amendment and contaminant immobilization necessitates a comprehensive understanding of its long‑term aging behavior under natural conditions. In this study, the transformation of HC in weakly alkaline soil was investigated over a 12‑month period. The aged HC exhibited substantial structural changes, with specific surface area, pore volume, and pore size increasing by 288%, 28%, and 122%, respectively. These modifications were mainly attributed to the leaching of labile organic matter, minerals, and surface debris, which was consistent with observed declines in electrical conductivity and hemicellulose content. Boehm titration, X‑ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) analyses revealed significant changes in oxygen‑containing functional groups (OCGs), including a decrease in carboxyl group acidity from 1.38 mmol·g⁻¹ to 0.46–0.49 mmol·g⁻¹, an increase in lactone acidity from 0.24 mmol·g⁻¹ to 0.59–0.60 mmol·g⁻¹, and a consequent reduction in total acidity from 1.92 mmol·g⁻¹ to 1.36–1.39 mmol·g⁻¹. Aging time was identified as the dominant driver of these physicochemical transformations. Despite the decline in total acidity, the enhanced porosity resulted in an approximately twofold increase in the Pb(II) adsorption capacity of HC. These findings provide valuable insights for the application of HC in sustainable soil remediation.

Self-powered ultraviolet (UV) photodetectors based on metal halide perovskites are hindered by inefficient charge extraction and severe interfacial recombination. To address the challenge, we report a multidimensional synergistic strategy centered on electron transport layer (ETL) engineering. Our approach integrates three complementary components: a compositionally graded indium-tin-zinc oxide (ITZO) ETL fabricated by modulated sputtering to create an optimized band alignment for charge extraction, an SnO2 nanocrystal interlayer for interfacial passivation and hole blocking, and zwitterionic betaine molecules for bulk defect healing in the MAPbCl3 absorber. The resulting photodetector achieves record-high performance with an ultralow dark current of 4.4 pA, a high responsivity of 282.5 mA/W, a near-unity external quantum efficiency of 95.9%, along with fast response of 3.6/3.6 ms and excellent operational stability. Furthermore, we demonstrate a uniform 10 & times; 10-pixel array that serves dual functions as both the receiver and a physical entropy source in a secure UVA optical communication system based on physically unclonable functions. This work establishes a viable paradigm of multidimensional interface engineering for high-performance self-powered perovskite optoelectronics, with implications for secure optical communication and broader photonic applications.

To address the growing demand for lithium amidst its limited supply, it is crucial to explore diverse and economically viable lithium resources to alleviate the pressure. Oilfield brine offers significant potential, particularly due to their reduced land and freshwater requirements for lithium extraction, which dramatically lowers costs and provides environmental benefits. However, the recovery of lithium from oilfield brine is relatively under-explored yet due to highly excess of coexisted magnesium and particularly calcium as well as extensive pretreatment process. To tackle this challenge, we reported a direct lithium extraction method using tris(2-ethylhexyl) phosphate (TOP)-FeCl3 solvent extraction system in this work. The proposed system achieved superior Li+ binding affinity with 77 % extraction in single stage and especially ultrahigh selectivity for Li+/ Mg2+ (separation factor: 5737) and Li+/Ca2+ (separation factor: 96) from real oilfield brine containing 52.1 g center dot L-1 Mg2+ and 84.4 g center dot L-1 Ca2+. The results significantly outperform traditional tri-n-butyl phosphate (TBP)-FeCl3 system, where Li+/Ca2+ selectivity is neglectable. The extraction mechanism was investigated using UV-visible, Raman spectroscopy, ESI-MS and slope ratio method, suggesting [Li center dot 2TOP center dot 2H2O][FeCl4] may be the active lithium complex species during extraction process in our system. The increased hydrophobicity and extended carbon chain compared to TBP molecule may contribute to the extraordinary selectivity and stability. This work presents a comprehensive extraction process and offers new insights into optimizing extractant structures to achieve enhanced selectivity. These results demonstrate that TOP-FeCl3 extraction system is highly promising for the industrial recovery of Li+ from real oilfield brine.

The dissolution loss of extractant into aqueous solution during lithium solvent extraction from salt lakes poses a significant issue. We found that branched chains of neutral organophosphorus extractants provide suitable steric hindrance, enhancing lithium extraction efficiency and Li/Mg selectivity. Additionally, increasing the number of alkyl chains in organophosphorus extractants increases their hydrophobicity, thereby reducing extractant dissolution loss during the extraction process. Based on these findings, a novel extraction system comprising tri (2-ethylhexyl) phosphate (TOP), FeCl3, and 4-methyl-2-pentanone (MIBK) was explored. The extraction conditions, including the Fe/Li molar ratio, diluents, phase ratio, and stripping conditions, were thoroughly investigated and optimized. The extraction mechanism was elucidated at the molecular level using FT-IR, Raman, NMR, and density functional theory (DFT) calculations. The results demonstrated that the TOP-FeCl3-MIBK system achieved an 85 % extraction efficiency for Li+ in a single stage, with a Li+/Mg2+ separation factor reaching 5842, surpassing previously reported data in the literature. 31 P NMR and 7 Li NMR analyses revealed that the TOP and tributyl phosphate (TBP) complexes existed in different forms within the organic phase. Slope analysis indicated that the stoichiometric ratio of the extraction complex involving Li+, TOP, and MIBK was LiFeCl4 & sdot;TOP & sdot;MIBK. Furthermore, DFT calculations indicated that the TOP complex was more stable than the TBP complex after extraction. We anticipate that our findings will pave the way for the development of a series of novel extractants with higher Li/Mg selectivity by enhancing steric hindrance and incorporating longer alkyl chains to minimize dissolution loss. We expect this research to inspire the development of similar neutral organophosphorus extractants.

Lithium exhibits superior electrochemical properties are attributable to its unique electron configuration and exceptionally low standard reduction potential, and it isa prevalent component in batteries and energy storage systems. The demand for lithium and its derivatives has increased dramatically as a consequence the rapid expansion of the emerging energy and storage industries. Nevertheless, the present mining and large-scale production capacities are inadequate to satisfy this mounting demand. In comparison to conventional salt- lake brines and hard rock deposits, oilfield brine has attracted considerable attention due to its high lithium concentration and lower production costs. In this work, a trioctyl- phosphate (TOP)-sodium phosphotungstate extraction system has been developed for direct lithium extraction (DLE) from raw oilfield brine. The ion transfer mechanism underlying metal uptake was elucidated by Fourier-transform infrared (FT-IR) spectroscopy and P-31 nuclear magnetic resonance (P-31-NMR) analysis. It is evident that DLE, due to its high selectivity, increased recovery efficiency and reduced carbon footprint, represents a promising avenue for overcoming the limitations of traditional lithium extraction methods and advancing sustainable resource development.

Constructing high-efficiency through-space charge-transfer (TSCT)-type thermally activated delayed fluorescence (TADF) blue emitters that simultaneously exhibit a high radiative decay rate (krs) and a high reverse intersystem crossing rate (kRISC) remains a significant challenge. Herein, spatially confined "X"-shaped TSCTTADF emitters are developed, which consist of planar 3,6-di-tert-butyl-9H-carbazole (tBuCz) donors, 2,4,6-triphenyl-1,3,5-triazine (for DTRZ-tBuCz) and 2,6-difluorobenzonitrile (for DFBN-tBuCz) acceptors, as well as phenyl bridging groups. Both emitters exhibit face-to-face donor/acceptor alignments and efficient intramolecular TSCT. Interestingly, the two emitters display strong intramolecular donor/acceptor interactions based on the "X"-shaped structure, which opens efficient intramolecular multi-channel TSCT, improving the krs and kRISC values. In the 15 wt% and 20 wt% doped films, DTRZ-tBuCz and DFBN-tBuCz exhibit blue TADF with high fluorescence efficiency (Phi PL) of 89 % and 91 %, accompanied by krs/kRISC values of 2.32 x 107 s- 1/4.2 x 105 s- 1 and 1.05 x 107 s- 1/9.03 x 105 s-1, respectively. Organic light-emitting diode (OLED) fabricated with DFBNtBuCz emitter achieve current efficiencies (CE) and external quantum efficiencies (EQE) reaching 34.1 cd/A and 18.7 %, along with low efficiency roll-offs. This study reveals that increasing intramolecular TSCT channels by constructing spatially confined molecules is an effective approach to simultaneously enhance the krs and kRISC of TSCT-TADF emitters, which is of great significance for the development of blue TSCT-TADF OLEDs.

The targeted recovery of cesium from high-salinity brines or radioactive wastewater is becoming increasingly vital due to its crucial function in cutting-edge technologies and environmental remediation efforts. Layered sulfides, especially thiostannate, have demonstrated strong selectivity in cesium extraction. Yet, studies on their selective mechanisms remain focused on traditional interlayer mass transfer and affinity coordination. The contribution of inherent structural properties, especially vertical ion transport channels, to selectivity has not been clarified. In this study, we report a novel ammonium-intercalated lamellar thiostannate, (NH4)2Sn3S7 (NTS), which exhibits remarkable selectivity for Cs+ over Na+ (separation factor: 608), K+ (370), Mg2+ (432), Ca2+ (823), and Rb+ (13) in real brine solutions. The dual ion-selective angstrom-scale channels were revealed via single-crystal structure analysis. Combined with the mechanism analysis of DFT calculation, it is further shown that Sn-vacancy channel (diameter: 4.53 & Aring;) in the vertical direction, rather than the horizontal interlayer one (free-spacing: 3.91 & Aring;), dominated the cation diffusion. The stable framework and matched size work together to accomplish Cs+ sieving with sub-angstrom precision. These findings provide an unprecedented insight into the transfer mechanism of layered metal sulfide materials. This work clearly demonstrates that precise sieving for extremely similar ions can be achieved through vacancy-engineered channels in two-dimensional materials.

Quasi‐two‐dimensional (quasi‐2D) perovskites are promising candidates for blue light‐emitting diodes (LEDs) because of their combined quantum‐ and dielectric‐confinement effects. By judiciously controlling the material components and phase distributions, it is more feasible to modulate the wavelength of quasi‐2D perovskite emitters to desired pure‐blue emission for display applications compared with the widely investigated mixed‐halide 3D perovskites and colloidal quantum dots with ultra‐small sizes. Employing quasi‐2D perovskites is also advantageous in circumventing the severe phase separation in blue mixed‐halide perovskites with elevated chlorine ratios and fragile surface properties of quantum dots. During the past several years, extensive efforts have been devoted to optimizing the film properties of blue quasi‐2D perovskite and device engineering of corresponding LEDs, enabling rapid progress in the device performance. This review first introduces fundamental structural and photophysical properties of quasi‐2D perovskite materials, and comprehensively summarizes strategies for modulating the blue quasi‐2D perovskite films. The review focuses on the key phase modulation related to the materials and interface engineering, as well as the perovskite film manufacturing process. Then, the remaining challenges on blue LEDs based on quasi‐2D perovskites are discussed, and finally perspectives on desired efforts on the materials and interfacial contacts toward further performance improvements are provided.

Direct and efficient recovery of lithium from precipitation mother liquor has garnered increasing attention, but challenges remain due to the low concentration of Li+ and high Na+ excess. To address these issues, we proposed a synergistic extraction system using 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HPMBP) as the extractant and Cyanex 923 as the synergist, which exhibits high selectivity for lithium in industrial mother liquors. In a single-stage extraction, HPMBP-Cyanex 923 achieved 85% Li+ extraction with only 4% Na+ and K+ from a real mother liquor solution containing 1.46 g/L Li+, 67 g/L Na+ and 2.57 g/L K+. The total organic carbon (TOC) test showed that HPMBP-Cyanex 923 exhibited significantly lower dissolution loss (220 mg/L) compared to that of the commonly used benzoyl-1,1,1-trifluoroacetone (HBTA, 432 mg/L), indicating superior hydrophobicity, which is essential for a green extraction process. The results demonstrate that 97% Na+ in the organic phase can be scrubbed prior to Li+ stripping, and much lower acid concentration (0.2 M HCl) is required to strip the lithium due to a lower pK a value of pyrazolone compared to traditional beta-diketones. Single-crystal analysis, slope analysis, and DFT calculations revealed the observation of a binuclear structure, [Li2(PMBP)2(TBPO)2], which could serve as a general structural formula for systems involving pyrazolones and an organophosphorus co-ligand with a short alkyl chain. This work presents a novel lithium extraction system that offers enhanced selectivity and hydrophobicity, along with a lower stripping acid requirement compared to traditional beta-diketones. These features make it highly promising for future industrial applications.

An asymmetric dual-gate heterointerface-regulated artificial synapse (HRAS) is developed, utilizing a main gate with distinct ion concentrations and a lateral gate to receive synaptic pulses, and through dielectric coupling and ionic effects, formed indium tin zinc oxide (ITZO) dual-interface channels that allow precise control over channel charge, thereby simulating multi-level coordinated actions of dual-neurotransmitters. The lateral modulation of the lateral gate significantly regulates ionic effects, achieving the intricate interplay among lateral inhibition/enhancement and short-/long-term plasticity at a multi-level scale for the first time. This interplay enables the HRAS device to simulate frequency-dependent image filtering and spike number-dependent dynamic visual persistence. By combining temporal synaptic inputs with lateral modulation, HRAS harnesses spatiotemporal properties for bio-inspired cryptographic applications, offering a versatile device-level platform for secure information processing. Furthermore, a novel dual-gate input neural network architecture based on HRAS has been proposed, which aids in weight update and demonstrates enhanced recognition capabilities in neural network tasks, highlighting its role in bio-inspired computing.

Blue perovskite light-emitting diodes (PeLEDs) based on mixed halide quasi-two-dimensional (Q-2D) perovskites encounter obstacles including phase instability, defect-induced non-radiative recombination, and ion migration. This work proposes a bifunctional molecular, L-alanine benzyl ester p-toluenesulfonate (LABEP), to synergistically modulate phase distribution and passivate defects in Br/Cl-mixed Q-2D perovskite films. The sulfonic (-SO3H) and amino (-NH2) groups in LABEP coordinate with undercoordinated Pb2+, suppressing the formation of n = 1 phases while promoting higher-n phases (n >= 2), thereby enhancing quantum confinement and yielding a hypsochromic emission at 478 nm. LABEP also reduces surface roughness of the perovskite thin film and improves interfacial contact, significantly alleviating shunt current. Furthermore, hydrogen bonding between LABEP and halide ions inhibits ion migration, stabilizing the perovskite structure under operational bias. As a result, the external quantum efficiency (EQE) of the PeLED shows a 2.6-fold enhancement at 478 nm with a narrow FWHM of 20.7 nm. Spectral and operational stability is also markedly enhanced, stemming from suppressed defect-assisted recombination and ion migration. Our findings establish a molecular engineering strategy for achieving efficient and stable blue PeLEDs, offering pivotal perspectives into phase engineering and defect management in perovskite optoelectronics.