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In recent years, there has been considerable push toward the biomedical applications with active particles, which have great potential to revolutionize disease diagnostics and therapy. The direct penetration of active particles through the cell membrane leads to more efficient intracellular delivery than previously considered endocytosis processes but may cause membrane disruption. Understanding fundamental behaviors of cell membranes in response to such extreme impacts by active particles is crucial to develop active particle-based biomedical technologies and manage health and safety issues in this emerging field. Unfortunately, the physical principles underlying the nonequilibrium behaviors from endocytosis to direct penetration remain elusive, and experiments are challenging. Here, we present a computed dynamic phase diagram for transmembrane transport of active particles and identify four characteristic dynamic phases in endocytosis and direct penetration according to the particle activity and membrane tension. The boundaries dividing these phases are analytically obtained with theoretical models, elucidating the nonequilibrium physics and criteria for the transition between different phases. Furthermore, we numerically and experimentally show three distinct dynamic regimes related to the interplay between necking and wrapping during the endocytosis process of active particles, which strikingly contrast the regimes for passive particles. Overall, these findings could be useful for sharpening the understanding of basic principles underlying biological issues related to the safe and efficient biomedical applications of such emerging matters.

Room-temperature lasing based on low-dimensional GaAs nanowires (NWs) is one of the most critical and challenging issues in realizing near-infrared lasers for nanophotonics. In this article, the random lasing characteristics based on GaAs NW arrays have been discussed theoretically. According to the simulation, GaAs/AlGaAs core–shell NWs with an optimal diameter, density, and Al content in the shell have been grown. Systematic morphological and optical characterizations were carried out. It is found that the GaAs NWs with the additional growth of the AlGaAs shell exhibit improved emission by about 2 orders of magnitude at low temperatures, which can be attributed to the suppression of crystal defects. At room temperature, lasing was observed with a threshold around 70.16 mW/cm2, and the random lasing mechanism was discussed in detail. This work is of great significance for the design of random cavities based on semiconductor NWs, which is important for optoelectronic integration.

The efficiency and stability issues of perovskite light-emitting diodes, especially at high brightness, need to be urgently solved for displays and lighting applications. Herein we present a simple chemical washing method called solvent sieve to resolve the phase dimension issue of metal halide perovskites. After being sieved, undesirable defect-rich low-nphases are selectively screened out of perovskite multi-quantum-well structures. With better intrinsic structure refinement, the sieved perovskites demonstrated not only a record external quantum efficiency, current efficiency, and T50lifetime of 29.5%, 127.4 cd A−1, and 18.67 h at 12,000 cd m−2(the equivalent of over 50,317 h or 5.7 years at 100 cd m−2), respectively, with a maximum luminance of over 147,872.8 cd m−2, but also extraordinary resistance to air and moisture, maintaining over 75% of film photoluminescence quantum yield and 80% of device EQE after being stored at ambience for 100 days. The simple solvent sieve treatment we reported here confirms the feasibility of metal halide perovskites for luminescence and unleashes the efficiency and stability potentials of high-brightness perovskite light-emitting diodes for future commercial applications.

Inverted perovskite light-emitting diodes (PeLEDs) based on quantum dots (QDs) are some of the most promising candidates for next-generation lighting and display applications. Due to the strong fluorescence quenching caused by zinc oxide, high performance in such inverted devices remains challenging. Here, we report an efficient inverted green CsPbBr3QDs LED using an emitting buffer layer. Ultrathin CsPbBr3QD emitters act as the buffer layer to reduce the interface luminescence quenching reaction at the ZnO/upper emitting layer interface, increasing the probability of exciton recombination within the emissive layer and regulating the charge transport, leading to effective carrier recombination. The resulting device exhibits an external quantum efficiency of 13.1%, enhanced by about 4.7 times compared with that without a buffer layer device. This work provides a path to fabricating high-performance inverted PeLEDs.

In this work, low-dimensional blue-emitting CsPbBr3nanoplatelets were prepared. Changes in the surface morphology of NPLs after long-term storage in a humid environment were observed by transmission electron microscopy. The reason for the CsPbBr3NPLs emission change from blue to green is found to be the loss of ligand and ion migration. Microwave treatment was demonstrated to improve the photostability and electrical stability of the samples. Based on the temperature-dependent and power-dependent photoluminescence measurement, it was concluded that both surface and internal defects of the sample decrease after microwave treatment. The ultrafast decay pathway of perovskite was thoroughly analyzed, and the ligand loss was found to be a deprotonation process, while the ion migration is a vacancy-driven and charge redistribution process. After microwave treatment, the residual polar DMSO solvent volatilizes, reducing the chance of structural collapse, and the surface and internal structural defects are reduced. In turn, the Br–ion can exist more stably on its surface. As a result, the defect migration pathway is reduced, and photostability and smaller magnitude photocurrent hysteresis can be obtained, which will provide an effective strategy for the optimization and stability improvement of blue-light optoelectronic devices.

High silicon dioxide content enables as a cement substitute. This study explored recycling RHA and RAP in cement stabilised macadam (CSM) to produce a pavement base material. Laboratory experiments covering strength, flexibility, shrinkage, and resistance to temperature variation were conducted on CSM with RAP (40% by weight of natural aggregates) and RHA at 0%, 20%, 40%, 60%, and 80% weight of cement. The results indicated that the compressive strength, resilient modulus, and tensile strength of CSM increased with curing time while the increasing rate and strength after curing decreased with the addition of RHA. The resistance to thermal changes, moisture loss, and the freeze-thaw cycle could be maintained by replacing 20 wt.% (or lower content) cement with RHA. These findings suggest that replacing 20 wt.% of cement with RHA and 40 wt.% of natural aggregates with RAP can generate qualified and environmental pavement base material.

Recently, the development of materials with circularly polarized luminescence (CPL) has attracted numerous attentions owing to their potential applications in various fields. Among diverse mechanisms for the origin of chiroptical properties in low dimensional semiconductors (LDS), the self-assembly approach provides a powerful technique for acquisition of strong chiroptical activity. Benefiting from this approach, LDS could be endowed with CPL in which the dissymmetry factor, a vital parameter for evaluating the performance of CPL, could be greatly improved. In this review, state-of-the-art of self-assembled LDS will be summarized. The current challenges and perspectives in this emerging field are also presented. This review could not only provide insights of the fundamentals of self-assembled chirality, but also shine light for designing CPL-active functional nanomaterials toward their applications based on novel optoelectronic devices.

Perovskite quantum dot light-emitting diodes (QLEDs) are potential candidates for next-generation displays due to their high color purity and wide color gamut. Due to the strong electron-accepting ability of poly[bis(4-phenyl) (2,4,6-trimethylphenyl) amine] (PTAA), quantum dot (QD) films are prone to be charged, which leads to the imbalance of charge injection and the increase of nonradiative recombination, ultimately affecting the performance of the QLEDs. Here, we compared and studied two polymers, poly(methyl methacrylate) (PMMA) and poly(vinyl pyrrolidone) (PVP), as the hole interface buffer layers of QD films, which effectively reduced the defect density, suppressed nonradiative recombination, and greatly improved the efficiency and stability of QLEDs. The devices with PMMA achieved a maximum external quantum efficiency of 20.71%.

Understanding physicochemical interactions and mechanisms related to the cell membranes of lives under extreme conditions is of essential importance but remains scarcely explored. Here, using a combination of computer simulations and experiments, we demonstrate that the structural integrity and controllable permeability of cell membranes at high temperatures are predominantly directed by configurational entropy emerging from distorted intermolecular organization of bipolar tethered lipids peculiar to the extremophiles. Detailed simulations across multiple scales─from an all-atom exploration of molecular mechanism to a mesoscale examination of its universal nature─suggest that this configurational entropy effect can be generalized to diverse systems, such as block copolymers. This offers biomimetic inspiration for designing heat-tolerant materials based on entropy, as validated by our experiments of synthetic polymers. The findings provide new insight into the basic nature of the mechanism underlying the adaptation of organisms to extreme conditions and might open paths for designed materials inspired by entropic effects in biological systems.

Conformation is the key to revealing the physical characteristics of macromolecular systems and receives tremendous interest from the fields of polymer physics and biological materials. The conformational entropy, related to the number of conformations of the macromolecule, plays a predominant role in the structural formation, transition, and dynamics of macromolecular systems. In this review, we present a comprehensive overview of the research, development and applications of the conformational entropy in complex macromolecular systems. We begin by discussing the physical origin of the conformational entropy based on statistical mechanics of macromolecules in classical polymer physics, and then introduce the recent progress on the predictive modeling of the conformational entropy, associated with a variety of typical macromolecular systems. Furthermore, we also highlight several principles and rules, which have been harnessed to manipulate the structural organization of complex macromolecular systems through the conformational entropy. We anticipate that this review will further promote fundamental research in polymer physics, and offer intriguing prospects for applications in complex macromolecular systems including biomacromolecules, grafted nanoparticles, and polymer nanocomposites.

Recently, deep-learning-based low-light video enhancement methods have drawn wide attention and achieved remarkable performance. However, limited by the difficulty in collecting dynamic low-light and well-lighted video pairs in real scenes, how to construct video sequences for supervised learning and design a low-light enhancement network for real dynamic video remains a challenge. In this paper, we propose a simple yet effective low-light video enhancement method (LVE-S2D), which generates dynamic video training pairs from static videos, and enhances the low-light video by mining dynamic temporal information. To obtain low-light and well-lighted video pairs, a sliding window-based dynamic video generation mechanism is designed to produce pseudo videos with rich dynamic temporal information. Then, a siamese dynamic low-light video enhancement network is presented, which effectively utilizes temporal correlation between adjacent frames to enhance the video frames. Extensive experimental results demonstrate that the proposed method not only achieves superior performance on static low-light videos, but also outperforms the state-of-the-art methods on real dynamic low-light videos.

Purpose: Partial nephrectomy (PN) is the main treatment strategy for localized renal cell carcinoma (RCC). However, for RCC with high anatomical complexity, PN remains a challenge for urologists. Therefore, this study aimed to evaluate the functional oncological outcomes and safety of laparoscopic partial nephrectomy (LPN) versus open partial nephrectomy (OPN) in localized RCC patients with highly anatomical complexity (R.E.N.A.L. score ≥ 10). Patients and methods: We retrospectively studied 575 patients who underwent PN at our center between January 2007 and December 2017. After propensity score-matching (PSM), 137 patients treated with LPN and 54 patients treated with OPN were balanced into 97 and 44 pairs. Patient demographics, and extensive perioperative and prognostic data were recorded and compared. Results: In the matched group, the OPN group had significantly less eGFR loss than the LPN group (2.57 ml/min/1.73 m2vs. 31.59 ml/min/1.73 m2, P< 0.001). The recurrence-free survival (P= 0.287), overall survival (P= 0.296), cancer-specific survival (P= 0.664), and cardiocerebrovascular disease-specific survival (P= 0.341) were equivalent between groups. The rates of minor (P= 0.621) and major (P= 0.647) complications were also similar between groups. Conclusions: This PSM cohort study showed that OPN resulted in better renal function preservation than LPN in localized RCC patients with high anatomical complexity, and had comparable oncological and safety outcomes after long-term follow-up. These findings may help improve clinical decision-making for localized RCC patients with high anatomical complexity.

All-polymer solar cells (all-PSCs) have received extensive attention due to their excellent mechanical robustness and performance stability. However, the power conversion efficiency (PCE) of all-PSCs still lags behind those of organic solar cells (OSCs) based on non-fullerene small molecule acceptors. Herein, we report highly efficient all-PSCs viasequential deposition (SD) with donor and acceptor layers coated sequentially to optimize the film microstructure. Compared with the bulk heterojunction (BHJ) all-PSCs, an optimized morphology with vertical component distribution was achieved for the SD-processed all-PSCs due to the synergistic effect of swelling of polymer films and using additive. Such strategy involves using chlorobenzene as the first layer processing-solvent for polymer donor, chloroform as the second processing-solvent for polymer acceptor with trace 1-chlor-onaphthalene, efficiently promoting exciton dissociation and charge extraction and reducing trap-assisted recombination. Consequently, over 16% all-PSCs fabricated viaSD method was realized for the first time, which is much higher than that (15.2%) of its BHJ counterpart and also among the highest PCEs in all-PSCs. We have further demonstrated the generality of this approach in various all-polymer systems. This work indicates that the SD method can yield excellent all-PSCs and provides a facile approach to fabricating high-performance all-PSCs.

A new proton-promoted in situ ligand exchange strategy based on CsPbI3quantum dots.The ligand exchange strategy maintains the quantum confinement effect of quantum dots and significantly improves the stability and photophysical properties of CsPbI3quantum dots.The performance of light-emitting diodes based on CsPbI3quantum dots is significantly improved, the external quantum efficiency is increased from 18.63% to 24.45%, and the half-operational lifetime is increased by 70 times.

The densest packings of identical spherical colloidal nanocrystals in a thin cylinder generally give rise to confinement-induced chiral ordering. Here, we demonstrate that entropy can invalidate Pauling’s packing rules for the nanocrystals confined in wide cylinders and novel ordered phases, where chiral ordering is broken, emerge. The nucleation and growth of spherical colloidal nanocrystals in the wide cylinders exhibit unique mechanisms which are distinctly different from that of thin ones. Furthermore, theoretical models which capture the essential physics of the ordering transitions are developed to reproduce the achiral ordering and reveal that the ordered phases are thermodynamically stable and stabilized through confinement-mediated entropic effect. These findings demonstrate that entropy arising from thermal motion can invalidate Pauling’s packing rules of spherical colloidal nanocrystals confined in cylinders, which provides new insights into confinement physics of colloidal particles and might inspire nonintuitive design rules for the fabrication of novel ordered phases through confinement.

The transport of nanoparticles in semiflexible networks, which form diverse principal structural components throughout living systems, is important in biology and biomedical applications. By combining large-scale molecular simulations as well as theoretical analysis, we demonstrate here that nanoparticles in polymer networks with semiflexible strands possess enhanced heterogeneous diffusion characterized by more evident hopping dynamics. Particularly, the hopping energy barrier approximates to linear dependence on confinement parameters in the regime of moderate rigidity, in contrast to the quadratic dependence of both its soft and hard counterparts. This nonmonotonic feature can be attributed to the competition between the conformation entropy and the bending energy regulated by the chain rigidity, captured by developing an analytical model of a hopping energy barrier. Moreover, these theoretical results agree reasonably well with previous experiments. The findings bear significance in unraveling the fundamental physics of substance transport confined in network-topological environments and would provide an explanation for the dynamics diversity of nanoparticles within various networks, biological or synthetic.

Activation and surface reactions of CO and H2on ZnO powders and nanoplates under CO hydrogenation reaction conditions were (quasi) in situ studied using temperature programmed surface reaction spectra, diffuse reflectance Fourier transform infrared spectroscopy, inelastic neutron scattering spectroscopy and electron paramagnetic resonance. CO undergoes disproportion reaction to produce gaseous CO2and surface carbon adatoms, and adsorbs to form surface formate species. H2adsorption forms dominant irreversibly-adsorbed surface hydroxyl groups and interstitial H species and very minor surface Zn-H species. Surface formate species and hydroxyl groups react to produce CO2and H2, while surface carbon adatoms are hydrogenated by surface Zn-H species sequentially to produce CH(a), CH2(a), CH3(a) and eventually gaseous CH4. The ZnO nanoplates, exposing a higher fraction of Zn-ZnO(0001) and O-ZnO(000–1) polar facets, are more active than the ZnO powders to catalyze CO hydrogenation to CH4. These results provide fundamental understanding of the reaction mechanisms and structural effects of CO hydrogenation reaction catalyzed by ZnO-based catalysts.

ObjectiveWe aimed to elucidate the mutual regulation mechanism of ubiquitin-specific protease 22 (USP22) and hypoxia inducible factor-1α (HIF1α), and the mechanism they promote the stemness of hepatocellular carcinoma (HCC) cells under hypoxic conditions.DesignCell counting, migration, self-renewal ability, chemoresistance and expression of stemness genes were established to detect the stemness of HCC cells. Immunoprecipitation, ubiquitination assay and chromatin immunoprecipitation assay were used to elucidate the mutual regulation mechanism of USP22 and HIF1α. HCC patient samples and The Cancer Genome Atlas data were used to demonstrate the clinical significance. In vivo USP22-targeting experiment was performed in mice bearing HCC.ResultsUSP22 promotes hypoxia-induced HCC stemness and glycolysis by deubiquitinating and stabilising HIF1α. As direct target genes of HIF1α, USP22 and TP53 can be transcriptionally upregulated by HIF1α under hypoxic conditions. In TP53 wild-type HCC cells, HIF1α induced TP53-mediated inhibition of HIF1α-induced USP22 upregulation. In TP53-mutant HCC cells, USP22 and HIF1α formed a positive feedback loop and promote the stemness of HCC. HCC patients with a loss-of-function mutation at TP53 and high USP22 and/or HIF1α expression tend to have a worse prognosis. The USP22-targeting lipopolyplexes caused high tumour inhibition and high sorafenib sensitivity in mice bearing HCC.ConclusionUSP22 promotes hypoxia-induced HCC stemness by a HIF1α/USP22 positive feedback loop on TP53 inactivation. USP22 is a promising target for the HCC therapy.

Inorganic perovskites such as CsPbBr3have attracted intensive research attention due to their excellent thermal stability and high photoluminescence quantum efficiency. With the decrease of the material’s dimension, quantum confinement effects will take place, which will induce many interesting properties. Here, quasi two-dimensional perovskite nanoplatelets (NPLs) and three-dimensional perovskite nanocrystals (NCs) have been grown, and their optical properties have been compared and discussed. It is interesting to find that the photon energy of CsPbBr3NPLs hardly changes with temperature due to strong electron–phonon interaction. At the same time, the strong quantum confinement effect results in a smaller Stokes shift and a faster fluorescence lifetime. In addition, although the NPLs have many surface defects, they exhibit a relatively strong negative thermal quenching effect of emission. These results demonstrate the unique optical properties of perovskite NPLs that can pave the way for future nanoscale devices.

Partially hydrolyzed polyacrylamide (HPAM) is widely used in oil recovery, but the HPAM residues also induce environmental pollution. In this study, two strains of bacteria, SCE2 and NMYGYB4, have been isolated from oilfield slickwater and identified as Tistrella bauzanensis(SCE2) and Brucellasp. (NMYGYB4). The optimal biodegradation conditions of Tistrella bauzanensisSCE2 were inoculation time 36 h, shaking speed 175 rpm, inoculum amount 3% (v/v), pH 3.0, and incubation temperature 37 °C with urea and glucose as the nitrogen and carbon sources. And the optimal biodegradation conditions of Brucellasp. NMYGYB4 were 12 h, 185 rpm, 2% (v/v), pH 7.0 and 37 °C with yeast powder and sucrose as the nitrogen carbon sources. HPAM removal rate of Tistrella bauzanensisSCE2 and Brucellasp. NMYGYB4 reached 75.3% and 63.59% at optimal conditions. The degraded samples were analyzed with GPC, FTIR, 1H NMR and HPLC. The results showed that HPAM was broken into small fragments, and amide group has been converted into carboxyl group, and no toxic acrylamide monomer was produced. The specific activities of extracellular amidases of Tistrella bauzanensisSCE2 and Brucellasp. NMYGYB4 were 5.31 U/mg and 4.79 U/mg, respectively. This work will provide novel bacteria strains for HPAM-containing wastewater treatment.

CeO2nanocubes (c-CeO2), nanoparticles (p-CeO2), and nanorods calcined at 500 °C (r-CeO2-500) and 700 °C (r-CeO2-700) were used as supports to synthesize a series of Ni/CeO2catalysts for the propane combustion and oxidative dehydrogenation of propane (ODHP) reactions. The Ni-CeO2interaction greatly promotes the reducibility of CeO2, but CeO2morphology-dependent Ni-CeO2interaction was observed to form different speciation of Ni species (Ni2+dissolved in CeO2, highly dispersive NiO, NiO aggregate) and oxygen species (strongly activated oxygen species, medially activated oxygen species, weakly activated oxygen species) in various Ni/CeO2catalysts. Ni-CeO2interaction is stronger in Ni/c-CeO2catalysts than in other Ni/CeO2catalysts. Different morphology-dependences of Ni/CeO2catalysts in propane combustion and ODHP reactions were observed. The Ni/r-CeO2-500 catalyst with the largest strongly activated oxygen species is most catalytic active in the propane combustion reaction while the Ni/c-CeO2catalyst with the largest amount of weakly activated oxygen species exhibits the best catalytic performance in the ODHP reaction. Thus, the CeO2morphology engineering strategy is effective in finely tuning the metal-CeO2interaction and the reactivity of oxygen species to meet the requirements of different types of catalytic oxidation reactions.

Understanding the rotational diffusion dynamics and underlying physical mechanism of rod-like particles in the confinement environments of macromolecular networks is of great importance in many fields. Herein, by combining large-scale simulations as well as theoretical analysis, we demonstrate that the thick rods, with rod diameter comparable with or even larger than the mesh size, in macromolecular networks possess enhanced heterogeneous rotational diffusion characterized by evident hopping among various preferred angles. Through quantifying the shape-dependent rotation, three characteristic rotational dynamics, i.e., Brownian, hopping, and restricted, are identified, which leads to a phase diagram of these rotational patterns related to the diameter and length of the rods. We find that the strong dynamic correlation between the hopping of the rotational and translational dynamics occurs at the boundary between the hopping and restricted rotational dynamics, beyond which the transitional dynamics presents diverse dynamic patterns during the rotational hopping. Furthermore, we develop an analytical model that captures all the regimes of the characteristic rotational patterns, resulting in a mechanistic interpretation of the emergence of the hopping rotational dynamics. The findings bear significance in unraveling the fundamental physics of anisotropic particles transporting in confined mediates like macromolecular networks.

The hybrid halide double-perovskite family is a highly diverse system that allows a wide range of property tunings via structural variations. Using organic components instead of small A-site cations to reduce the dimensionality of the structure and doping metal cations can modulate their structure and improve the optoelectronic performance. Here, by introducing an organic cationic ligand morpholine (Mor), we report on a new family of double-perovskite-derived halides (Mor)2ABX6(A= Na, K; B= In, Bi; X= Cl, Br) with several unique types of one-dimensional (1D) structures constituted by [AX4O2] and [BX6] octahedron units. These materials are nonemissive at room temperature, while with an Sb3+-doping strategy, the photoluminescence can be drastically enhanced. For (Mor)2KInX6, their quantum efficiencies are improved to near unity via Sb3+doping. Meanwhile, for (Mor)2KBiX6, the photoluminescence improvement from Sb3+doping is negligible. With density functional theory calculations, (Mor)2KInBr6and (Mor)2KBiBr6have been identified to have direct- and indirect- band gap, respectively. This work expands a new material space for organic–inorganic hybrid double-perovskite-derived materials and provides insights into tuning their optical properties.

A series of Pd catalysts supported on commercial Ce-Zr solid solution(Pd/CZ) calcined at different temperatures( 750, 900 and 1050 °C) was prepared viaan incipient wetness impregnation method. The activities of the fresh and hydrothermally aged Pd/CZ catalysts were tested for total oxidation of CO and C3H8. For CO oxidation, the activity of either fresh or aged Pd/CZ catalysts decreased with the elevating of calcination temperature of CZ support, with a fresh catalyst calcined at 750 °C possessing the highest activity and hydrothermal stability. For C3H8total oxidation, the activity of Pd/CZ catalysts could be improved by increasing the calcination temperature of support. However, the aged Pd/CZ catalysts showed higher activity than corresponding fresh Pd/CZ catalysts. The turnover frequency( TOF) over Pd/CZ catalyst for CO oxidation increased with increasing reduction ability of the catalysts, with a fresh catalyst calcined at 750 °C having the highest value(0.27 s−1). However, the TOF of Pd/CZ catalyst for C3H8total oxidation was mainly affected by the size of Pd particles, and large Pd particles possessed a higher activity, with the highest TOF value(0.96 s−1) obtained over an aged catalyst calcined at 1050 °C.

This paper investigated the effect of microfibers (carbon fibers and basalt fibers) and macrofibers (plastic steel fibers) on the mechanical properties of coral concrete. A total of 192 specimens were designed with carbon fibers (CFs), basalt fibers (BFs), and plastic steel fibers (PSFs) as variables. The compressive strength, splitting tensile strength, axial compressive strength, and elastic modulus of hybrid fiber-reinforced coral concrete were studied by testing. The results show that all three fibers can improve the mechanical properties of coral concrete. The microfiber major positively affects the stage before the macrocracks are formed, and the positive effect of macrofibers major works on the stage after the macrocracks are appeared. Hybrid addition of microfibers and macrofibers can further improve the mechanical properties. The cube compressive strength, splitting tensile strength, axial compressive strength, and elastic modulus can be improved by 11.2%, 25.5%, 14.1%, and 8.5%, respectively, when incorporating the optimum hybrid fiber dosages (CFs 0.15%, BFs 0.15%, and PSFs 4 kg/m3).

Stable organic radicals represent a unique type of functional materials for a broad scope of applications in optoelectronic and spintronic devices. A central challenge toward these applications is how to suppress the inter-radical aggregation that often causes aggregation-induced photoluminescence quenching and limits the correlation lifetime of the electron spins from the radicals. Here, we report an effective approach to fine-tuning luminescence and spin dynamics using a series of polyester-tethered single radicals, with a common core of carbazole-triphenylmethyl radical but different chains of polyesters with distinct glass transition temperature and rigidity. The rigidity of the polymeric matrices plays a critical role in tuning the luminescence and electron spin resonance of the radicals. The tunable properties of luminescence and electron spin dynamics as well as the robust photostability of such polymer-tethered single radicals represent important attributes for cutting-edge applications in optoelectronic devices and quantum information technologies.

Hybrid multifunctional materials have great potential in a wide variety of applications due to their flexible combination of organic and inorganic components. Introducing chiral organic modules into the metal halide frameworks can effectively generate multifunctional materials, achieving new functionalities with noncentrosymmetric structures. Here, by incorporating (R)- or (S)-piperidine-3-carboxylic acid (R/S-PCA) as the templating cation, we report the synthesis and characterization of three pairs of new 2D chiral hybrid Cu(I) halides, namely, (R/S-PCA)CuBr2, (R/S-PCA)CuBr2·0.5H2O, and (R/S-PCA)CuI2. These chiral Cu(I) halides crystallize in the noncentrosymmetric space group C2 and belong to a new structural type similar to layered silicates. The optical absorption edges of these chiral materials can be tuned by changing the halide or upon the absorption of water and range from 2.70 to 3.66 eV. A dynamic conversion between (R/S-PCA)CuBr2and (R/S-PCA)CuBr2·0.5H2O occurs through exposure to moisture or vacuum drying along with changes in the reversible bandgap and photoluminescence. Chiroptical properties such as circular dichroism, circular polarized light emission, and second harmonic generation are investigated. Density functional theory calculations (DFT) show the indirect and direct bandgap natures of these Cu(I) halides and reveal the mechanism for the broadband self-trapped exciton emission at the excited state. The fascinating structural type, chiroptical properties, and reversible hydrochromic behavior of these Cu(I)-based halides make them viable candidates for next-generation multifunctional optoelectronic materials.

Understanding the behaviors of nanoparticles at interfaces is crucial not only for the design of novel nanostructured materials with superior properties but also for a better understanding of many biological systems where nanoscale objects such as drug molecules, viruses, and proteins can interact with various interfaces. Theoretical studies and tailored computer simulations offer unique approaches to investigating the evolution and formation of structures as well as to determining structure–property relationships regarding the interfacial nanostructures. In this feature article, we summarize our efforts to exploit computational approaches as well as theoretical modeling in understanding the organization of nanoscale objects at the interfaces of various systems. First, we present the latest research advances and state-of-the-art computational techniques for the simulation of nanoparticles at interfaces. Then we introduce the applications of multiscale modeling and simulation methods as well as theoretical analysis to explore the basic science and the fundamental principles in the interfacial nanoparticle organization, covering the interfaces of polymer, nanoscience, biomacromolecules, and biomembranes. Finally, we discuss future directions to signify the framework in tailoring the interfacial organization of nanoparticles based on the computational design. This feature article could promote further efforts toward fundamental research and the wide applications of theoretical approaches in designing interfacial assemblies for new types of functional nanomaterials and beyond.

Featuring high olefin selectivity, hexagonal boron nitride (h-BN) has emerged recently as an attractive catalyst for oxidative dehydrogenation of propane (ODHP). Herein, we report that dispersion of vanadium oxide onto BN facilitates the oxyfunctionalization of BN to generate more BOxactive sites to catalyze ODHP via the Eley–Rideal mechanism and concurrently produce nitric oxide to initiate additional gas-phase radical chemistry and to introduce redox VOxsites to catalyze ODHP via the Mars–van Krevelen mechanism, all of which promote the catalytic performance of BN for ODHP. As a result, loading 0.5 wt % V onto BN has doubled the yield of light alkene (C2–C3) at 540–580 °C, and adding an appropriate concentration of NO in the reactants further enhances the catalytic performance. These results provide a potential strategy for developing efficient h-BN-based catalysts through coupling gas-phase and surface reactions for the ODHP process.

Understanding the effect of curvature and topological frustration on self-assembly yields insight into the mechanistic details of the ordering of identical subunits in curved spaces, such as the assembly of viral capsids, growth of solid domains on vesicles, and the self-assembly of molecular monolayers. However, the self-assembly of nanoparticles with anisotropic surface topology and compartmentalization on curved surfaces remains elusive. By combining large-scale molecular simulations as well as theoretical analysis, we demonstrate here that the interplay among anisotropy, curvature, and chain conformation induces tethered Janus nanoparticles to self-assemble into diverse novel structures on a sphere, including binary nanocluster (CB), trinary nanocluster (CT), nanoribbon (RN) and hexagon with centered reverse (HR), which are mapped on a phase diagram related to the length asymmetry of tethered chains and Janus balance of the nanoparticles. The dynamical mechanism for the formation of these structure states is analyzed by examining the detailed kinetic pathways as well as free energy. We also show that the centered-reverse state is more prone to emerging around the topological defects, indicating the defect-enhanced entropy effect on a curved surface. Finally, the analytical model that rationalizes the regimes of these structure states is developed and fits simulations reasonably well, resulting in a mechanistic interpretation based on the order through entropy. Our findings shed light on curvature engineering as a versatile strategy to tailor the superstructures formed by anisotropic building blocks toward unique properties.

In recent years, core–shell lead halide perovskite nanocrystals (PeNCs) and their devices have attracted intensive attention owing to nearly perfect optoelectronic properties. However, the complex photophysical mechanism among them is still unclear. Herein, monodispersed core–shell PeNCs coated with an all-inorganic cesium lead bromide (CsPbBr3) shell epitaxially grown on the surface of formamidinium lead bromide (FAPbBr3) PeNCs were synthesized. Through power- and temperature-dependent photoluminescence (PL) measurements, it is found that the electronic structure of the core–shell FAPbBr3/CsPbBr3PeNCs has a quasi-type II band alignment. The presence of Cs+in the shell limits ion migration and helps to stabilize structural and optical properties. On this basis, after being exposed to pulsed nanosecond laser for a period, an amplified spontaneous emission (ASE) can be observed, which is attributed to the effective passivation induced by laser irradiation on defects at the interface. The ASE threshold of the core–shell PeNCs showing high structural and optical stability is 447 nJ/cm2under pulsed nanosecond optical pumping. The results that are demonstrated here provide a new idea and perspective for improving the stability of perovskite and can be of practical interest for the utilization of the core–shell PeNCs in optoelectronic devices.

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