Extraordinary Stability Research Articles

Facile Synthesis of Amorphous MnOx Catalysts for Efficient Ozone Elimination in Domestic Refrigerators

ABSTRACT Amorphous manganese oxide catalysts, aimed at efficient ozone removal in refrigerators, were synthesized using a simple redox method. Factors like crystallinity of structure, textural properties, and Fe doping significantly affect the catalyst’s performance. The Fe-doped KMF-250 showcased outstanding ozone decomposition capabilities, efficiently eliminating 10,000 ppb of ozone at an average rate of ca. 13.3 , under conditions of 6 °C and 36% relative humidity in a refrigerator chamber (144 L). Moreover, this catalyst exhibits extraordinary stability, outperforming existing commercial catalysts in terms of both durability and efficiency. The incorporation of even a minimal amount of Fe (0.84 wt%) considerably raised the amount of low-valence Mn, resulting in more crystal defects and oxygen vacancies. The existence of Fe in MnOx was also found playing an important role in promoting the desorption of the oxygen species and enhancing the oxygen mobility to generate oxygen vacancies, both of which contribute to the quick recovery of the catalyst. The catalyst’s large specific surface area, combined with optimal Fe doping, are crucial for its superior catalytic performance. This research delivers a potent MnOx catalyst suitable for ozone removal in refrigerators and viable for mass production.

Manipulating electron linking units and side chains for high-performance all-polymer photodetectors with stability over 5000 h

All-polymer photovoltaic devices have attracted extensive attention for their promising applications in various flexible devices. Although abundant polymer donors with superior properties are developed, new polymer acceptors are urgently required to optimize or update the performances of the devices. Herein, three novel polymer acceptors, namely PY-DTT, PY-DTP-C, and PY-DTP-Ph, based on dithienothiophene (DTT) and dithienopyrrole (DTP) with alkyl and aryl side chains as the linking units respectively are synthesized and employed in the all-polymer photodetectors (all-PPDs). The PY-DTP-Ph shows broader absorption, stronger intermolecular interaction, and more coplanar molecular conformation compared with the other two acceptors. Blending with donor PM6, the PY-DTP-Ph based all-PPDs exhibit maximum responsivity of 292.1 mA W−1 and specific detectivity of 5.4 × 1013 cm Hz1/2 W−1 at a bias of −0.1 V. Furthermore, the device achieves fast response speed (τr/τf = 1.2/21.8 μs) and a large linear dynamic range of 105.0 dB. Intriguingly, the photodetectors present extraordinary air stability for 5000 h, attributing to the ideal miscibility and morphology of the blend films. These results demonstrate close relationships between the electron linking units, side chains and the basic properties of polymer acceptors, which in turn affects the performances of the photodetector devices.

The C-terminus is essential for the stability of the mycobacterial channel protein MspA.

Outer membrane proteins perform essential functions in uptake and secretion processes in bacteria. MspA is an octameric channel protein in the outer membrane of Mycobacterium smegmatis and is structurally distinct from any other known outer membrane protein. MspA is the founding member of a family with more than 3000 homologs and is one of the most widely used proteins in nanotechnological applications due to its advantageous pore structure and extraordinary stability. While a conserved C-terminal signal sequence is essential for folding and protein assembly in the outer membrane of Gram-negative bacteria, the molecular determinants of these processes are unknown for MspA. In this study, we show that mutation and deletion of methionine 183 in the highly conserved C-terminus of MspA and mutation of the conserved tryptophan 40 lead to a complete loss of protein in heat extracts of M. smegmatis. Swapping these residues partially restores the heat stability of MspA indicating that methionine 183 and tryptophan 40 form a conserved sulfur-π electron interaction, which stabilizes the MspA monomer. Flow cytometry showed that all MspA mutants are surface-accessible demonstrating that oligomerization and membrane integration in M. smegmatis are not affected. Thus, the conserved C-terminus of MspA is essential for its thermal stability, but it is not required for protein assembly in its native membrane, indicating that this process is mediated by a mechanism distinct from that in Gram-negative bacteria. These findings will benefit the rational design of MspA-like pores to tailor their properties in current and future applications.

Centennial Isomers: A Unique Fluorinated Azobenzene Macrocyclus with Dual Stability Over 120 Years

AbstractA macrocyclic azobenzene with unique thermal stability, demonstrating potential for use in optical data storage material is presented: The Z‐isomer of this novel photoswitch exhibits unparalleled thermal stability, with a thermal half‐life surpassing 120 years at 25 °C. This stability is attributed to the strategic fluorination at two ortho‐ and both para‐positions. Comparative analyses involving its non‐fluorinated counterpart, ortho‐only‐fluorinated variant, and open‐chain analog are performed. Employing NMR and UV–vis spectroscopy, X‐ray diffraction, alongside Arrhenius, Eyring, and DFT calculations, revealed insights into its extraordinary stability. Furthermore, when incorporated into poly(methylmethacrylate), this material showcase efficient switching with visible light in the solid state, emphasizing its potential for optical data storage applications.

Engineering Symmetry-Breaking Centers and d-Orbital Modulation in Triatomic Catalysts for Zinc-Air Batteries.

Unraveling the configuration-activity relationship and synergistic enhancement mechanism (such as real active center, electron spin-state, and d-orbital energy level) for triatomic catalysts, as well as their intrinsically bifunctional oxygen electrocatalysis, is a great challenge. Here we present a triatomic catalyst (TAC) with a trinuclear active structure that displays extraordinary oxygen electrocatalysis for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), greatly outperforming the counterpart of single-atom and diatomic catalysts. The aqueous Zn-air battery (ZAB) equipped with a TAC-based cathode exhibits extraordinary rechargeable stability and ultrarobust cycling performance (1970 h/3940 cycles at 2 mA cm-2, 125 h/250 cycles at 10 mA cm-2 with negligible voltage decay), and the quasi-solid-state ZAB displays outstanding rechargeability and low-temperature adaptability (300 h/1800 cycles at 2 mA cm-2 at -60 °C), outperforming other state-of-the-art ZABs. The experimental and theoretical analyses reveal the symmetry-breaking CoN4 configuration under incorporation of neighboring metal atoms (Fe and Cu), which leads to d-orbital modulation, a low-shift d band center, weakened binding strength to the oxygen intermediates, and decreased energy barrier for bifunctional oxygen electrocatalysis. This rational tricoordination design as well as an in-depth mechanism analysis indicate that hetero-TACs can be promisingly applied in various electrocatalysis applications.

Improving sulfur transformation of lean electrolyte lithium–sulfur battery using nickel nanoparticles encapsulated in N‐doped carbon nanotubes

AbstractEfficient redox reactions of lean electrolyte lithium–sulfur (Li–S) batteries highly rely on rational catalyst design. Herein, we report an electrocatalyst based on N‐doped carbon nanotubes (CNT)‐encapsulated Ni nanoparticles (Ni@NCNT) as kinetics regulators for Li–S batteries to propel the polysulfide‐involving multiphase transformation. Moreover, such a CNT‐encapsulation strategy greatly prevents the aggregation of Ni nanoparticles and enables the extraordinary structural stability of the hybrid electrocatalyst, which guarantees its persistent catalytic activity on sulfur redox reactions. When used as a modified layer on a commercial separator, the Ni@NCNT interlayer contributes to stabilizing S cathode and Li anode by significantly retarding the shuttle effect. The corresponding batteries with a 3.5 mg cm−2 sulfur loading achieve the promising cycle stability with ∼85% capacity retention at the electrolyte/sulfur ratios of 5 and 3 μL mg−1. Even at a high loading of 12.2 mg cm−2, the battery affords an areal capacity of 7.5 mA h cm−2.

Facile synthesis and modification of Fe2O3 nanorod arrays on carbon paper as efficient negative electrodes for supercapacitors

In this research, Fe2O3 nanorod arrays grown on carbon fiber paper were studied, and carbon-coated Fe2O3 (Fe2O3 @C) and sulfurized Fe2O3 @C (Fe2O3 @C-S) were fabricated by carbon coating and sulfurization processes. To promote the application of these materials in supercapacitors, their electrochemical properties were systematically investigated. Based on the results, the materials obtained utilized a pseudocapacitive mechanism for energy storage. Specifically, Fe2O3 exhibited a moderate specific capacitance and extraordinary cycling stability, and no degradation was observed after 10,000 cycles. Impressively, sulfurization greatly enhanced the rate capability and specific capacitance of the sample. As a result, Fe2O3 @C-S attained a specific capacitance of 976.4 mF cm–2 at 4 mA cm–2 and a robust rate capability of 97.30% at 20 mA cm–2, outperforming Fe2O3 @C (84.39%) and Fe2O3 (70.55%) and demonstrating good cycling stability (92.9%). Notably, Fe2O3 @C-S was active as a positive electrode material; thus, a symmetric supercapacitor was assembled, which yielded a volumetric energy density of 1.46 mWh cm–3 at 16.71 mW cm–3 and maintained an energy density of 0.91 mWh cm–3 even at 145.63 mW cm–3. Moreover, the device exhibited good cycling stability with a capacity retention of 88.3% after 10,000 cycles at 10 mA cm–2. The integration of Fe2O3 nanorod arrays on conductive substrates, coupled with the above modifications, strongly promoted the material’s energy storage performance. Our study emphasized the significant potential of Fe2O3 @C-S as an efficient electrode material for supercapacitors.

KxVPO4F (x∼0): A New High‐Voltage and Low‐Stain Cathode Material for Ultrastable Calcium Rechargeable Batteries

AbstractThe utilization of high‐voltage intercalation cathodes in calcium‐ion batteries (CIBs) is impeded by the substantial size and divalent character of Ca2+ ions, which result in pronounced volume alterations and sluggish ion mobility, consequently causing inferior reversibility and low energy/power densities. To tackle these issues, polyanionic K‐vacant KxVPO4F (x∼0, designated as K0VPF) is proposed as high‐voltage and ultra‐stable cathode material in CIBs. The K0VPF demonstrates a decent calcium storage capacity of 75 mAh g−1 at 10 mA g−1 and remarkable capacity retention of 84.2% over 1000 cycles. The average working voltage of the K0VPF is 3.85 V versus Ca2+/Ca, representing the highest value reported for CIB cathodes to date. The combined experimental and theoretical investigations revealed that the low volume changes and hopping diffusion barriers contribute to the extraordinary stability and high‐power capabilities, respectively, of K0VPF. The distribution of Ca ions into polyanionic frameworks with pronounced spatial separation effectively attenuates the Ca2+–Ca2+ repulsive force and thus augmenting the Ca migration kinetics. The high voltage of K0VPF is attributed to the inductive effect from the largely electronegative fluorine. In conjunction with a calcium metal anode and a compatible electrolyte, Ca metal full cells featured a record‐high energy density of ≈300 Wh kg−1.

Enhancing the Potential of Fused Heterocycle-Based Triarylhydrazone Photoswitches.

Triarylhydrazones represent an attractive class of photochromic compounds offering many interesting features including high molar absorptivity, good addressability, and extraordinary thermal stability. In addition, unlike most other hydrazone-based photoswitches, they effectively absorb light above 365 nm. However, previously prepared triaryhydrazones suffer from low quantum yields of the Z→E photoisomerization. Here, we have designed a new subclass of naphthoyl-benzothiazole hydrazones that balance the most beneficial features of previously reported naphthoyl-quinoline and benzoyl-pyridine triarylhydrazones. These preserve the attractive absorption characteristics, exhibit higher thermal stability of the metastable form than the former and enhance the rate of the Z→E photoisomerization compared to the later, as a result of the weakening of the intramolecular hydrogen bonding between the hydrazone hydrogen and the benzothiazole moiety. Introducing the benzothiazole motif extends the tunability of the photochromic behaviour of hydrazone-based switches.

A Two-Step Mechanism for Creating Stable, Condensed Chromatin with the Polycomb Complex PRC1.

The Drosophila PRC1 complex regulates gene expression by modifying histone proteins and chromatin architecture. Two PRC1 subunits, PSC and Ph, are most implicated in chromatin architecture. In vitro, PRC1 compacts chromatin and inhibits transcription and nucleosome remodeling. The long disordered C-terminal region of PSC (PSC-CTR) is important for these activities, while Ph has little effect. In cells, Ph is important for condensate formation, long-range chromatin interactions, and gene regulation, and its polymerizing sterile alpha motif (SAM) is implicated in these activities. In vitro, truncated Ph containing the SAM and two other conserved domains (mini-Ph) undergoes phase separation with chromatin, suggesting a mechanism for SAM-dependent condensate formation in vivo. How the distinct activities of PSC and Ph on chromatin function together in PRC1 is not known. To address this question, we analyzed structures formed with large chromatin templates and PRC1 in vitro. PRC1 bridges chromatin into extensive fibrillar networks. Ph, its SAM, and SAM polymerization activity have little effect on these structures. Instead, the PSC-CTR controls their growth, and is sufficient for their formation. To understand how phase separation driven by Ph SAM intersects with the chromatin bridging activity of the PSC-CTR, we used mini-Ph to form condensates with chromatin and then challenged them with PRC1 lacking Ph (PRC1ΔPh). PRC1ΔPh converts mini-Ph chromatin condensates into clusters of small non-fusing condensates and bridged fibers. These condensates retain a high level of chromatin compaction and do not intermix. Thus, phase separation of chromatin by mini-Ph, followed by the action of the PSC-CTR, creates a unique chromatin organization with regions of high nucleosome density and extraordinary stability. We discuss how this coordinated sequential activity of two proteins found in the same complex may occur and the possible implications of stable chromatin architectures in maintaining transcription states.

Introduction of SnS2 to Regulate the Ferrous Disulfide Phase Evolution for the Construction of Triphasic Heterostructures Enabling Kinetically Accelerated and Durable Sodium Storage

AbstractTransition metal sulfides (TMSs) still confront the challenges of capacity fading and inferior fast‐charging capability for sodium storage. The rational design of heterostructures enables a new approach to conquer these drawbacks. In this work, a hierarchical structure consisting of SnS2 nanosheets and FeS2 microrods with triphasic heterostructures is proposed by the facile secondary growth and sulfidation process. The introduction of tin sources regulates the proportion of pyrite and marcasite phases, thereby achieving the triphasic heterostructures comprising pyrite, marcasite FeS2, and SnS2. When served as anode material for sodium‐ion batteries, the optimized sample exhibits a high reversible capacity (901 mAh g−1) and durable cycling performances (827 mAh g−1 after 200 cycles at 1 A g−1 and 742 mAh g−1 after 700 cycles at 5 A g−1). Paring with the commercial Na3V2(PO3)3 cathodes, the full‐cell also delivers extraordinary cyclic stability with a high capacity of 618 mAh g−1 (based on the weight of anode material) after 200 cycles at 1 A g−1 (98.7% capacity retention). The hierarchical structure with adjustably triphasic heterogeneous interfaces alleviates the volumetric expansion and interfacial passivation of active material, while modulating the energy band structure and inducing the build‐in electric fields to boost Na+/electrons transport rate.

Li-Zn alloy patch for defect-free polymer interface film enables excellent protection effect towards stable Li metal anode

Constructing a smart polymer film with favorable lithium (Li) transport capability and mechanical flexibility for suppressing Li dendrite growth is an effective strategy. Unfortunately, the porosity and the swelling of the polymer membrane cannot completely prevent liquid electrolyte from sweeping through the artificial protection film, severely deteriorating the cyclic performance. Herein, we propose a defect-free hybrid film that consists of Li+ conductive lithium polyacrylate (LiPAA) polymer interface layer and Li-Zn alloy patch to tackle the critical problems of traditional polymer composite passivation film. The pinhole leaks of the polymer matrix are self-filled by Li-Zn alloy patches, enhancing the integrity of LiPAA film. Consequently, a defect-free hybrid film is nailed flat against the Li metal anode, exhibiting extraordinary stability in the liquid electrolyte and enabling perfect protection effect. This facile strategy produces a promising anode for next generation Li batteries.

A quinoxaline–benzothiadiazole heterotrimer for organic solar cells with extraordinary efficiency and stability

A new hybrid strategy synthesizes the TQT acceptor with thiadiazole and quinoxaline units. The resulting TQT-based OSC achieved 18.52% efficiency, topping linear trimer acceptor-based OSCs, while also exhibiting robust stability.

Adjusted MnO oxygen vacancy for highly selective ORR production of H2O2.

The oxygen reduction reaction (ORR) via the two-electron pathway is an important method of hydrogen peroxide (H2O2) production. This study demonstrates that MnO with different oxygen vacancies possesses great 2e- ORR activity. The H2O2 selectivity increased from 10% to 93% with increasing oxygen vacancy concentration by adjusting the reaction temperature and time. Moreover, the H2O2 yield of the optimal MnO reached 544.1 mmol g-1 h-1, and it showed extraordinary stability over a long period of time (10 000 circles CV), surpassing most of the reported transition metal catalysts. This provides a new strategy for efficient and low-cost electrochemical production of H2O2.

Enhancing photoelectrochemical performance and stability of Ti-doped hematite photoanode via pentanuclear Co-based MOF modification.

Modifying photoanodes with metal-organic frameworks (MOFs) as oxygen evolution reaction (OER) cocatalysts has emerged as a promising approach to enhance the efficiency of photoelectrochemical (PEC) water oxidation. However, designing OER-active MOFs with both high photo- and electrochemical stability remains a challenge, limiting the advancement of this research. Herein, we present a facile method to fabricate a MOF-modified photoanode by directly loading a pentanuclear Co-based MOF (Co-MOF) onto the surface of a Ti-doped hematite photoanode (Ti:Fe2O3). The resulting Co-MOF/Ti:Fe2O3 modified photoanode exhibits an enhanced photocurrent density of 1.80mA∙cm-2 at 1.23V, surpassing those of the Ti:Fe2O3 (1.53mA∙cm-2) and bare Fe2O3 (0.59mA∙cm-2) counterparts. Additionally, significant enhancements in charge injection and separation efficiencies, applied bias photon-to-current efficiency (ABPE), incident photon to current conversion efficiency (IPCE), and donor density (Nd) were observed. Notably, a minimal photocurrent decay of only 5% over 10h demonstrates the extraordinary stability of the Co-MOF/Ti:Fe2O3 photoanode. This work highlights the efficacy of polynuclear Co-based MOFs as OER cocatalysts in designing efficient and stable photoanodes for PEC water splitting applications.

A Brief Historical Overview and Mathematical Equations of Soliton

bstract: A soliton is a strongly stable, nonlinear, self-reinforcing, localised wave packet that maintains its shape even after colliding with other similar localised wave packets and propagates freely at a constant speed. The medium's balanced cancellation of nonlinear and dispersive effects is responsible for its extraordinary stability. Dispersive effects are a characteristics of several systems where a wave frequency determines how fast it travels. Subsequently, it was shown that soliton solutions offer stable solutions for a broad range of weakly nonlinear dispersive partial differential equations that characterise physical systems. Solitons have a self-restoring quality that makes them desirable for long-distance, high-speed transmissions. The strain on networks is quickly reaching a critical threshold as transmission speeds over longer distances are now approaching 40 Gbit/sec. In the future, solitons might offer intriguing alternatives.

Novel bipolar hosts for highly efficient green phosphorescent organic light-emitting diodes with slow efficiency roll-off

Organic light-emitting diodes (OLED) based on phosphorescent emitter promise 100 % internal quantum efficiency (IQE) theoretically, showing extensive applications in various fields. The guest phosphors are usually doped into appropriate host matrices to minimize unnecessary excitons quenching. Herein, three novel bipolar host materials (H1–H3) were developed. Pyridine or pyrimidine was selected as the electron-transporting n-type unit and indolocarbazole as hole-transporting p-type unit. Dibenzofuran was grafted onto the central pyridine or pyrimidine to enhance the electron-transporting ability based on its electron-deficient feature. Furthermore, dibenzofuran was also useful to enhance the thermal and amorphous stabilities of the generated host materials. These host materials are characterized by high glass transition temperatures over 150 °C and suitable energy levels. Thanks to strengthened microcavity effect, the top-emitting green phosphorescent OLEDs containing these hosts in emitting layer realized quite narrow spectra with full width at half maxima (FWHM) of ≤27 nm. Low turn on voltage of 2.01 V, high external quantum efficiency (EQE) up to 41.1 % and pretty stable emission color with ΔCIEy≤0.002 were achieved for these green devices. Moreover, these devices are characterized by extraordinary efficiency stability. A high EQE of 34.9 % was still remained at extremely high brightness of 10000 cd/m2, corresponding to an efficiency roll-off of less than 15 %. These host materials may find practical applications in highly efficient and stable OLED displays.

Synergetic oxidative esterification of 5-hydroxymethylfurfural using Pd-Au bimetallic nanocomposite under mild conditions

An innovative Pd and Au nanoparticles (NPs) supported polymeric matrix (PdAu@PS) as stable, heterogeneous and recyclable nanocomposite was developed for oxidative esterification of 5-hydroxymethylfurfural (5-HMF) to dimethyl-2,5-furandicarboxylate (DMFC) and methyl-5-(hydroxymethyl)furan-2-carboxylate (MHFC). The prepared nanocomposite offered DMFC (48% selectivity) and MHFC (50% selectivity) in maximum 94% conversion with 98% overall selectivity at 35 °C temperature under mild reagent conditions. In this catalytic conversion, the inter-electronic interactions existing between Pd and Au metals were proved to be responsible for extraordinary stability, reactivity and recyclability of the catalyst. The identification of intermediates through mass spectrometry and the insight of control experiments helped us in concluding the possible reaction pathway. Importantly, the bimetallic catalyst was excellently recycled for six cycles with slight loss in conversion and selectivity.

Preparation of a novel nanoparticle with extruded soy protein isolate-oat β-glucan: Interfacial properties and mechanism of emulsion stability

A novel nanoparticle was prepared with soy protein isolate (SPI)-oat β-glucan (OG) conjugates obtained by extrusion (extruded SPI-OG) to stabilize the emulsion. Extruded SPI-OG nanoparticles exhibited a spherical and stable structure. The 90 °C and 110 °C extruded SPI-OG nanoparticles had higher absolute value of zeta potential (13.35 mV and 12.24 mV, respectively) and an average particle size of less than 200 nm. Moreover, interfacial tension of nanoparticles increased with increasing extrusion temperature, but diffusion rate and surface hydrophobicity were decreased, while penetration rate (Kp) and rearrangement rate (Kr) increased and then decreased. The 90 °C and 110 °C extruded SPI-OG nanoparticles had the highest Kp and Kr, and increased by 38.14% and 40.11%, 175.16% and 168.15%, respectively, compared with Kp and Kr of SPI nanoparticles. And emulsion stabilized by these two nanoparticles exhibited the extraordinary emulsion stability of 81.64% and 80.07%, respectively (p > 0.05). These results demonstrated that adsorption rate of extruded SPI-OG nanoparticles to the oil-water interface decreased, but could rapid unfold and rearrange at the interface to form interfacial layer for stabilizing emulsion. And adsorption capacity and microstructure of emulsion also proved that more extruded SPI-OG nanoparticles could adsorb onto the interface to form a dense interfacial layer. This may provide a theoretical basis for novel nanoparticles as interfacial stabilizer in emulsion.

Triple coumarin-based 5-fluorouracil prodrugs, their synthesis, characterization, and release kinetics

5-Fluorouracil (5-FU) has been commonly used as a chemotherapy medication in cancer management. However, owing to its substantial side effects, limited selectivity, and tumor resistance, therapeutic usage of 5-FU has been called into doubt. In order to alter the physicochemical properties of 5-FU and improve its targeting, a coumarin-based-esterase-sensitive prodrug system was used to create nine 5-FU prodrugs, which were divided into three series of compounds, A, B, and C. The chemical structures of these prodrugs are confirmed by using FTIR, 1H-NMR, 13C-NMR, and mass spectrophotometers. The chemical stability of these prodrugs in simulated gastric and intestinal fluids as well as their release in human serum were measured spectrophotometrically. The outcomes showed that the synthetic prodrugs had extraordinary stability in the two stimulated fluids with relatively high half-lives, indicating that they can transit through the upper GIT portions without being harmed. The half-lives of the produced prodrugs in human serum vary from 391.30 to 517.94 min, demonstrating their ability to enter their target tissues undamaged and release their active components in pseudo-first-order kinetics. These components include 5-FU, coumarin or one of its derivatives, and one of the 5-FU biochemical modifiers, which are legumain-specific tripeptide, dichloroacetate, or leucovorin. In conclusion, It is hypothesized that the prepared triple coumarin-based 5-FU prodrugs offer several advantages, including improving the physicochemical properties of the parent drug, potentiating its anticancer activity, minimizing its toxic effects, boosting its oral bioavailability, and providing the capacity for specific targeting.