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Single‐atom alloys (SAAs) have gained increasing prominence in the field of selective hydrogenation reactions due to their uniform distribution of active sites and the unique host‐guest metal interactions. Herein, 15 SAAs are constructed to comprehensively elucidate the relationship between host‐guest metal interaction and catalytic performance in the selective hydrogenation of 4‐nitrostyrene (4‐NS) by density functional theory (DFT) calculations. The results demonstrate that the SAAs with strong host‐guest metal interactions exhibit a preference for N─O bond cleavage, and the reaction energy barrier of the hydrogenation process is primarily influenced by the host metal. Among them, Ir1Ni SAA stands out as the prime catalyst candidate, showcasing exceptional activity and selectivity. Furthermore, the Ir1Ni SAA is subsequently prepared through precise synthesis techniques and evaluated in the selective hydrogenation of 4‐NS to 4‐aminostyrene (4‐AS). As anticipated, the Ir1Ni SAA demonstrates extraordinary catalytic performance (yield > 96%). In situ FT‐IR experiments and DFT calculations further confirmed that the unique host‐guest metal interaction at the Ir‐Ni interface site of Ir1Ni SAA endows it with excellent 4‐NS selective hydrogenation ability. This work provides valuable insights into enhancing the performance of SAAs catalysts in selective hydrogenation reactions by modulating the host‐guest metal interactions. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) is a heterogeneous, multifactorial neurodegenerative disorder characterized by three neurobiological factors beta‐amyloid, pathologic tau, and neurodegeneration. There are no effective treatments for AD at a late stage, urging for early detection and prevention. However, existing statistical inference approaches in neuroimaging studies of AD subtype identification do not take into account the pathological domain knowledge, which could lead to ill‐posed results that are sometimes inconsistent with the essential neurological principles. Purpose: Integrating systems biology modeling with machine learning, the study aims to assist clinical AD prognosis by providing a subpopulation classification in accordance with essential biological principles, neurological patterns, and cognitive symptoms. Methods: We propose a novel pathology steered stratification network (PSSN) that incorporates established domain knowledge in AD pathology through a reaction‐diffusion model, where we consider non‐linear interactions between major biomarkers and diffusion along the brain structural network. Trained on longitudinal multimodal neuroimaging data, the biological model predicts long‐term evolution trajectories that capture individual characteristic progression pattern, filling in the gaps between sparse imaging data available. A deep predictive neural network is then built to exploit spatiotemporal dynamics, link neurological examinations with clinical profiles, and generate subtype assignment probability on an individual basis. We further identify an evolutionary disease graph to quantify subtype transition probabilities through extensive simulations. Results: Our stratification achieves superior performance in both inter‐cluster heterogeneity and intra‐cluster homogeneity of various clinical scores. Applying our approach to enriched samples of aging populations, we identify six subtypes spanning AD spectrum, where each subtype exhibits a distinctive biomarker pattern that is consistent with its clinical outcome. Conclusions: The proposed PSSN (i) reduces neuroimage data to low‐dimensional feature vectors, (ii) combines AT[N]‐Net based on real pathological pathways, (iii) predicts long‐term biomarker trajectories, and (iv) stratifies subjects into fine‐grained subtypes with distinct neurological underpinnings. PSSN provides insights into pre‐symptomatic diagnosis and practical guidance on clinical treatments, which may be further generalized to other neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

In this study, we elucidate the genesis and distribution patterns of Silurian hot shale hydrocarbon source rocks by utilizing a comparative analysis of the evolutionary characteristics of plate tectonic activity in the Paleo–Tethys Ocean and the sedimentary filling characteristics of key basins in North Africa, the Middle East, and South China. We propose an explanation for the sedimentary genesis of world-class Silurian hydrocarbon source rocks in the Paleozoic craton basin of the ancient Tethys tectonic domain. This is achieved by scrutinizing the plate tectonic activity and evolution of the ancient Tethys Ocean and combining these findings with the paleotectonic sedimentation background of North Africa, the Middle East, and South China. Additionally, we compare Silurian hydrocarbon source rocks from these regions. The deep-water stagnant environment of the land shelf favors the preservation of organic matter, thereby forming high-quality hydrocarbon source rocks. Conversely, the shallow-water body of the land shelf is more turbulent, thus resulting in the poorer preservation of organic matter and, consequently, lower-quality hydrocarbon source rocks. [ABSTRACT FROM AUTHOR]

The exploitation and design of high-efficiency catalysts have attracted extensive attention in the selective regulation of hydrogenation reactions; however, it remains a tremendous challenge currently. Herein, we report two kinds of nanosized Pt-based catalysts, including single-atom catalysts (SACs) and nanosized cluster catalysts (NCCs), anchored onto a CoAlOx support via the topotactic transformation of layered double hydroxides. The SAC (Pt1/CoAlOx) exhibits a >99% selectivity toward the hydrogenation of furfural (FAL) to furfuryl alcohol (FOL), while the NCC (Ptn/CoAlOx) shows a >99% selectivity for tetrahydrofurfuryl alcohol (THFOL) under a mild reaction condition (room temperature and a 0.1 MPa pressure of H2). Both in situ experiments and theoretical calculations reveal that the aggregation state (single atom or nanosized cluster) of Pt atoms influences the adsorption configuration of FAL, in which the adsorption of CO occurs on Pt single atoms over Pt1/CoAlOx and the adsorption of both CC and CO occurs on continuous Pt atoms over Ptn/CoAlOx. The structure–selectivity relationship substantiates that metal ensemble size has an important effect on the adsorption structure of the reaction substrate and thus results in the different selectivity of the hydrogenation reaction. [ABSTRACT FROM AUTHOR]

A high Schottky barrier height (ΦB) is one of the essential prerequisites for achieving high‐performance self‐powered Schottky‐barrier diode (SBD)‐based photodetector. The ΦB value is predominantly determined by the metal function and interface quality of the metal/semiconductor contact. 2D MXenes with adjustable work functions and dangling bond‐free properties are promising building blocks for constructing self‐powered SBD with high ΦB. Herein, a novel Ti3C2Tx MXene/Si hexagonal microhole array (SiHMA) van der Waals SBD is developed for the first time via a feasible solution process. Significantly, the device possesses a large ΦB up to ≈1.07 eV, which is among the highest for the Si‐based SBD. In consequence, the Ti3C2Tx/SiHMA SBD yields a large responsivity up to 302 mA W−1 and detectivity as high as 5.4 × 1013 Jones in a self‐powered model, surpassing the performance of most 2D material/Si photodiodes reported to date. Furthermore, it is demonstrated that featured and reliable fingertip photoplethysmogram (PPG) signals can be detected using the self‐powered SBD, enabling us to further accurately extract the heart rate (HR), and blood pressures (BP) using the PPG‐only method. This work paves the way for the construction of high‐performance MXenes‐based self‐powered SBDs for health monitoring. [ABSTRACT FROM AUTHOR]

Considering the inherent hydrophilic and porous nature of paper, the rapid absorption and diffusion of aqueous analyte solutions on paper-based SERS substrates may severely affect the Raman detection sensitivity and accuracy in the detection of target molecules. In this work, a series of hydrophobic CFP@PDA@AuNPs stripes were obtained through in situ synthesizing of gold nanoparticles (AuNPs) on a polydopamine (PDA)-decorated cellulose filter paper (CFP) and functionalized with perfluorodecanethiol (PFDT). When the SERS performance of the substrates was examined using 4-ATP, the hydrophobic CFP@PDA@AuNPs substrate showed superior sensitivity, reproducibility and stability due to the hydrophobic enrichment effect, with the detection limit decreasing to 10−9 M and the enhancement factor as high as 2.55 × 107. More importantly, it was feasible to apply the hydrophobic paper substrate as an excellent SERS sensor to detect methylene blue (MB) residues in lake water in a highly sensitive manner. The lowest detectable limit of MB was 100 nM, and it showed a low relatively standard deviation (RSD) value of 5.28%. Hydrophobic CFP@PDA@AuNPs stripes may serve as excellent sensors for target molecule detection and have tremendous potential in food security, and environmental and chemical detection. [ABSTRACT FROM AUTHOR]

Herein, TiSe2–C laminated heterojunction in situ derived from halogen ion (–Cl, –F) terminal functionalized Ti3C2Tx MXene was prepared by the solid-state reaction. Functional precursor of Cl-enriched MXene was synthesized by chloride molten etching method, and high-crystalline TiSe2–C laminated heterojunction was obtained after the selenylation process. For F-enriched MXene, abundant TiO2 nanoparticles could be acquired besides TiSe2–C lamination. Based on DFT calculation results, the byproduct TiO2 and amorphous carbon can continuously inject electrons to TiSe2, owing to the discrepancy of work functions. Excellent charge-carrier transportation peculiarity gives TiSe2–C lamination heterojunction excellent electrochemical performances and can also accelerate the kinetic process. Among them, TiSe2–Cl demonstrates a reversible capacity of 369.14 mA h g−1 at a current of 1 A g−1 and even keeps a high rate capacity of 372.26 mA h g−1 at 5 A g−1. This study provides a new idea to synthesize MXene derivatives for high performance sodium ion batterry anode materials. [ABSTRACT FROM AUTHOR]

All inorganic perovskite nanocrystals CsPbX3(X = Cl, Br, I) are the great potential candidates for the application of high-performance light emitting diodes (LED) due to their high Photoluminescence Quantum Yield (PLQY), high defect tolerance, narrow full-width half-maximum and tunable wavelength of 410–700 nm. However, the application of red-emitting (630–650 nm) CsPbBrxI3-x nanocrystals are perplexed by phase segregation due to the composition of mixed halides and the difference in halide ion mobility. Herein, we provide an effective strategy to suppressing the migration of Br/I ions through Ni2+ doping via a facile Hot-Injection method and the PLQY was improved as well. DFT calculations show that the introduction of Ni2+ causes a slight contraction of the host crystal structure, which improves the bond energy between Pb and halides and reduces the level of surface defects. Therefore, the phase stability is improved by Ni2+ doping because the phase segregation caused by ion migration in the mixed phase is effectively inhibited. Meanwhile, the non-radiative recombination in the exciton transition process is reduced and the PLQY is improved. What's more, benefiting from the suppressed ion migration and enhanced PLQY, we combine the Ni2+-doped CsPbBrxI3-x nanocrystals with different Br/I ratios and YAG: Ce3+ phosphors as color conversion layers to fabricate high efficiency WLED. When the ratio of Br/I is 9:11, WLED has a color coordinate of (0.3621, 0.3458), the color temperature of 4336 K and presents a high luminous efficiency of 113.20 lm W−1, color rendering index of 94.9 under the driving current of 20 mA and exhibits excellent stability, which shows great potential in the application of LED. [ABSTRACT FROM AUTHOR]

Transition metal sulfides (TMSs), especially cobalt-based sulfides have great potential use in battery anode materials. However, low coulombic efficiency and poor cycle stability limit their application in battery fabrication. In this work, a two-dimensional MOF material ZIF-9 was treated by a two-step calcination method that obtained a flower-shaped carbon skeleton coated with Co-vacancy, Co1−xS nanoparticles. The skeleton effectively restrains the volume expansion that happens on electrodes, which improved the electrical conductivity of the compound. The cobalt vacancy changes the local electronic structure and atomic populations; the DFT calculation also proves that this structure is beneficial to the migration of sodium ions and provides good cycling performance under high current density. According to our electronic experiments, Co1−xS@C exhibited good electrochemical performance, which maintains a capacity of about 300 mA h g−1 at a high current density of 5 A g−1 after 250 cycles. All results indicate the outstanding electrochemical performance of our composite material, especially under a high current density. This work may provide a method in MOFs-derived TMSs compounds to stimulate the potential of transition metal sulfide materials in energy storage. [ABSTRACT FROM AUTHOR]

Highly efficient and blue-emitting CsPbBr3 quantum dots were successfully synthesized by two-step supersaturated recrystallization under ambient condition. This method could control the particle size within 2.8 nm, thus resulting in strong quantum confinement effect of the products. The as-synthesized CsPbBr3 quantum dots presented outstanding optical properties with highest photo-luminescence quantum yield of 87.20% and longest PL lifetime of 12.24 ns. The blue light-emitting diode made from the CsPbBr3 quantum dots exhibited a CIE coordinate (0.14, 0.10), in good agreement with the standard blue CIE coordinate (0.14, 0.08) of National Television System Committee (NTSC). [ABSTRACT FROM AUTHOR]

Prussian blue analogues are potential competitive energy storage materials due to their diverse metal combinations and wide three-dimensional ion channels. Here, we prepared a new highly crystalline monoclinic nickel-doped cobalt hexacyanoferrate via a feasible and simple one-step co-precipitation method. In the process of sodium-ion de-intercalation, three stable charge and discharge platforms, which are consistent with the cyclic voltammetry performance, are seen for the first time, showing the function of nickel ions in Prussian blue. Furthermore, the charge transfer and structural evolution caused by the transmission of sodium ions were well revealed via ex situ XRD, ex situ XPS, and in situ EIS studies. Simulation calculations are performed relating to the energy band structure and the highest-occupied bonding orbitals of the system in different charge states, revealing the charge and discharge mechanism of the nickel-doped material and the reason for the emergence of the new platform at low voltages. In addition, NaNi0.17Co0.83Fe(CN)6 also delivers a striking capacity of 146 mA h g−1 and superior cyclability, with 93% capacity retention over 100 cycles; it can be considered as a promising alternative cathode material for use in sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Highlights: Dimensional gradient structure of sheet–tube–dots was constructed with CoSe2@CNTs–MXene for fast ion and electron transportation. Density functional theory study discloses the electrochemical difference of CoSe2@CNTs–MXene in ether/ester electrolyte system. Phase transformation of CoSe2@CNTs–MXene was analyzed by in situ XRD. The full cell based on CoSe2@CNTs–MXene anode was also assembled.Recently, abundant resources, low-cost sodium-ion batteries are deemed to the new-generation battery in the field of large-scale energy storage. Nevertheless, poor active reaction dynamics, dissolution of intermediates and electrolyte matching problems are significant challenges that need to be solved. Herein, dimensional gradient structure of sheet–tube–dots is constructed with CoSe2@CNTs–MXene. Gradient structure is conducive to fast migration of electrons and ions with the association of ether electrolyte. For half-cell, CoSe2@CNTs–MXene exhibits high initial coulomb efficiency (81.7%) and excellent cycling performance (400 mAh g−1 cycling for 200 times in 2 A g−1). Phase transformation pathway from crystalline CoSe2–Na2Se with Co and then amorphous CoSe2 in the discharge/charge process is also explored by in situ X-ray diffraction. Density functional theory study discloses the CoSe2@CNTs–MXene in ether electrolyte system which contributes to stable sodium storage performance owing to the strong adsorption force from hierarchical structure and weak interaction between electrolyte and electrode interface. For full cell, CoSe2@CNTs–MXene//Na3V2 (PO4)3/C full battery can also afford a competitively reversible capacity of 280 mAh g−1 over 50 cycles. Concisely, profiting from dimensional gradient structure and matched electrolyte of CoSe2@CNTs–MXene hold great application potential for stable sodium storage. [ABSTRACT FROM AUTHOR]

Lithium sulfide (Li2S) is an attractive cathode material for lithium–sulfur batteries due to its matching with the lithium‐metal‐free anode, but limited by its preparation and processing difficulty, low electronic conductivity, and high dissolution of polysulfide intermediates. Herein, a novel, low‐cost, and scalable method (termed as inverse fabrication route) is proposed to directly prepare Li2S‐based electrodes. This methodology uniformly anchors in situ generated Li2S nanocrystals with a controllable size of 5–10 nm on the woven carbon fibers (WCF) substrate to fabricate a spatial conductive network structure, which provides continuous high‐speed pathways for electron/ion transport. Furthermore, Li2S nanocrystals are encapsulated into a nitrogen/fluorine (N/F) codoped carbon framework to directly fabricate a spatial structure of Li2S‐nanocrystals @ doped‐carbon/WCF (Li2S @ DC/WCF) composite cathode. N/F codoped carbon yields certain catalytic effects on the electrochemical redox reaction for lithium–sulfur batteries, and N‐containing groups in carbon lead to a strong chemical interaction with Li2S/lithium polysulfides, thus improving the electrochemical reaction kinetics and suppressing the polysulfide shuttle. Hence, the as‐prepared Li2S @ DC/WCF composite cathode exhibits a high discharge capacity of 913 mA h g−1 at 0.2C, and the discharge capacity remains at 98% even after 200 cycles at 1C, corresponding to an average capacity decay of 0.01% cycle−1. [ABSTRACT FROM AUTHOR]

High-quality single-crystalline NbSe2 nanosheet arrays were successfully synthesized by a salt and hydrogen co-assisted CVD method, and the crystal structure and morphology of the material were investigated by XRD, Raman spectroscopy and TEM/HRTEM. The metallic electrical transport properties of the materials were validated by experimental measurement and DFT computation. The NbSe2 nanosheet array photodetectors showed very high responsivity and external quantum efficiency to UV light. [ABSTRACT FROM AUTHOR]

Surface engineering and doping are common methods used to enhance the emission properties of perovskite quantum dot light-emitting diodes (PeQLEDs), and more effective methods need to be developed. Here, we introduce a spin-coated trioctylphosphine oxide (TOPO) layer that spontaneously forms concave–convex micro grid structures between the hole-transport layer (TFB) and the CsPbBr3 quantum dot (QD) layer. The unique concave–convex micro grid structures change with the concentration of TOPO solution and the type of solvent, which may be caused by the surface tension. Spectral measurements reveal that the TOPO layer passivates the surface defects between the perovskite QDs. The finite-difference-time-domain (FDTD) method proves that these concave–convex micro grid structures also increase light output from the quantum dot light-emitting diodes (QLEDs). As a result, green perovskite QD light emitting diodes (LEDs) of 514 nm with a Luminous Efficiency (LE) of 3975 cd m−2, Current Efficiency (CE) of 18.8 cd A−1 and External Quantum Efficiency (EQE) of 6.7% can be achieved, which are improved three-fold compared to the CsPbBr3 QLEDs without the TOPO layer. Our work suggests that the micro grid structures of the TOPO layer provide a novel and facile way to enhance the performance of the perovskite QLEDs. [ABSTRACT FROM AUTHOR]

PbS quantum dots (QDs) were regarded as promising candidates for photoelectric devices because of their high absorption, multiple exciton generation effect and solution processability. However, their low charge carrier transport behavior impedes their wide application. Here, a ligand exchange process was introduced to fabricate PbS-QD + hybrid perovskite photodetectors. The photodetectors show a high sensitivity, low noise current and high stability under visible to near-infrared light illumination. The devices exhibited an impressive responsivity of ∼2 × 106 A W−1 and a high photoconductive gain of ∼3 × 106, respectively, with an applied bias of 5 V. Furthermore, the photodetectors display a large detectivity approaching 1015 Jones and a fast photoresponse up to 1 MHz at room temperature. These great performances suggest that the hybrid perovskite can well passivate the defects of PbS-QDs and provide new insight into the preparation of high-performance nano-devices. [ABSTRACT FROM AUTHOR]

MXenes have been demonstrated as a potential candidate in the field of photovoltaics and energy storage owing to their high transmittance, metallic conductivity and tunable work function. In this work, we introduce a two-dimensional (2D) structure of Ti3C2-MXene nanosheets into all inorganic CsPbBr3 solar cells as an interlayer to realize a better interfacial energy level alignment, which helps to eliminate the energy level mismatch, accelerate the hole extraction and reduce the recombination at the interface of perovskite/carbon electrode. In addition, the functional groups such as ＝O existing in the surface of Ti3C2-MXene nanosheets also provide strong interactions between the MXene and under-coordinated Pb atoms, which remarkably reduces the deep trap defects in the CsPbBr3 films. The device with the Ti3C2-MXene interlayer shows an impressive initial power conversion efficiency of 9.01% and long-term stability for over 1900 hours in a moisture environment and more than 600 hours under thermal conditions. [ABSTRACT FROM AUTHOR]

Bio-carbon is currently being widely explored for use in Na-ion battery anodes due to its abundance and facile fabrication process. However, the desire for higher energy density and reduced cost still calls for optimized precursors, together with suitable post-treatment. To that end, we present here the fabrication of typical carbon, featuring rich nanopore-decorated side-by-side holes, obtained from natural coir via a simple secondary air-activation method. As a result, a reversible capacity of 408 mA h g−1 at 20 mA g−1 is achieved. Attractively, even at a current density of 500 mA g−1, a specific capacity of 181 mA h g−1 and remarkable capacity retention of 93% after 500 cycles still can be achieved, thus highlighting the material's great potential for assisting the future realization of commercialized SIBs. [ABSTRACT FROM AUTHOR]

Primary alkylamines are generally used as ligands for the synthesis of colloidal II–VI group quantum dots (QDs). However, knowledge of the effects of these ligands on the nanocrystalline structure in the literature is scarce and often contradictory. Herein, the structural evolution of CdSe QDs synthesized with primary alkylamines of different chain lengths and concentrations and at various reaction temperatures has been investigated. Absorption spectroscopy, XRD, HRTEM and Fourier transform imaging were applied to characterize the structure of the CdSe QDs. The results demonstrate that CdSe QDs preferentially form the wurtzite structure with shorter-chain and higher-concentration primary alkylamines at higher reaction temperatures. In contrast, the zinc blende structure is formed in the presence of longer-chain and lower-concentration primary alkylamines at lower reaction temperatures. By precisely controlling the experimental conditions, CdSe QDs with a pure zinc blende phase have been successfully achieved. [ABSTRACT FROM AUTHOR]

Prussian blue analogs are receiving intense attention due to their high theoretical energy density and low cost, but their real applications are still hampered by poor electronic conductivity and cycling stability. Here, Na1.83Ni0.12Mn0.88Fe(CN)6 wrapped with graphene was synthesized by a facile co-precipitation method. The existence of RGO not only significantly increases the conductivity of the cathode, but also makes the framework much more robust during long cycling process. As the cathode, the Na1.83Ni0.12Mn0.88Fe(CN)6/RGO is able to deliver a high initial discharge capacity of 120mAhg−1 at a current density of 20mAg−1 with superior capacity retention of 96.7% after 100 cycles. Even at a current density of 1000mAg−1, the cell still delivers a capacity of 86mAhg−1, indicating outstanding rate capability. The results and the facile synthesis method enable Na1.83Ni0.12Mn0.88Fe(CN)6/RGO to the competitive for a future energy storage system. Na2NixMn1–xFe(CN)6/RGO coupled with regular cubic shapes was synthesized via a facile PVP-assisted co-precipitation method. The nanocomposite possessed a stable cubic framework doped with Ni and an improved electronic conductivity. A high electrochemical performance was obtained with high specific capacity of 120mAh g–1 and superior capacity retention of 96.6% after 100 cycles. [ABSTRACT FROM AUTHOR]

Designing Prussian blue with optimally exposed crystal planes and confining it in a conductive matrix are critical issues for improving its sodium storage performance, and will result in much improved sodium ion adsorption and diffusion, together with improved electron mobility. Here, we firstly illustrate through DFT simulations that the {100} lattice planes and [100] direction of the KxFeFe(CN)6 crystal are the preferred occupation sites and diffusion route for sodium ions. In addition, through coupling with RGO, KxFeFe(CN)6 electrodes exhibit better electronic conductivity. Accordingly, {100} plane-capped cubic K0.33FeFe(CN)6 wrapped in RGO was fabricated using a facile CTAB-assisted method. Due to the highly robust framework, higher specific surface area, greatly reduced number of lattice water defects and conductive RGO coating, K0.33FeFe(CN)6/RGO exhibits superior electrochemical performance in sodium-ion batteries. As a cathode, the RGO-coated K0.33FeFe(CN)6 yields an initial discharge–charge capacity of 160 mA h g−1 at a rate of 0.5C, and an excellent capacity retention of 92.2% at 0.5C and 90.1% at 10C after 1000 and 500 cycles. Furthermore, XRD, DFT simulation, XANES and EXAFS verified that the structural changes during the Na-ion insertion–extraction processes are highly reversible. All these results suggest that {100} plane-capped K0.33FeFe(CN)6/RGO has excellent potential as a cathode for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

The photoluminescence (PL) characteristics of MEH-PPV hybrid films blended with Au nanoparticles are studied in detail. Due to the strong coupling effect between the surface plasmon of Au nanoparticles and the emission of MEH-PPV, the introduction of Au nanoparticles could enhance the PL intensity and modulate the shape of absorption and excitation spectra, according to our steady spectroscopy experiments. Besides, the relaxation dynamic experiments show that the non-radiative rate in the hybrid system decreases. The temperature and the excitation intensity (EI)-dependent PL spectral data indicate that hybrid MEH-PPV films have lower activation energy and higher thermal exchange rate. As a result, the thermal accumulation effect and the non-linearity of EI-induced PL enhancement are suppressed in hybrid films. [ABSTRACT FROM AUTHOR]