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1.
J Colloid Interface Sci ; 677(Pt A): 842-852, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39126802

RESUMEN

The high theoretical specific energy and environmental friendliness of zinc-air batteries (ZABs) have garnered significant attention. However, the practical application of ZABs requires overcoming the sluggish kinetics associated with oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Herein, 3D self-supported nitrogen-doped carbon nanotubes (N-CNTs) arrays encapsulated by CoNi nanoparticles on carbon fiber cloth (CoNi@N-CNTs/CFC) are synthesized as bifunctional catalysts for OER and ORR. The 3D interconnected N-CNTs arrays not only improve the electrical conductivity, the permeation and gas escape capabilities of the electrode, but also enhance the corrosion resistance of CoNi metals. DFT calculations reveal that the co-existence of Co and Ni synergistically reduces the energy barrier for OOH conversion to OH, thereby optimizing the Gibbs free energy of the catalysts. Additionally, analysis of the change in energy barrier during the rate-determining step suggests that the primary catalytic active center is Ni site for OER. As a result, CoNi@N-CNTs/CFC exhibits superior catalytic activity with an overpotential of 240 mV at 10 mA cm-2 toward OER, and the onset potential of 0.92 V for ORR. Moreover, utilization of CoNi@N-CNTs/CFC in liquid and solid-state ZABs exhibited exceptional stability, manifesting a consistent cycling operation lasting for 100 and 15 h, respectively.

2.
Small ; : e2406683, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39192470

RESUMEN

Magnesium-lithium-ion hybrid batteries (MLIBs) have gained significant attention since the combination of a dendrite-free and low-cost magnesium anode with lithium-ion storage cathodes. However, the lack of high-performance cathodes has severely hindered their development, limited by the lower operating voltages of electrolytes. Herein, vanadium molybdenum disulfide nanosheets anchoring on flexible carbon cloth (VMS@CC) are constructed as high-performance cathodes for MLIBs, which inherit the electrochemical properties of high-voltage VS2 and high-capacity MoS2, simultaneously. By adjusting the V and Mo atomic ratio, the VMS@CC cathode for MLIBs delivers a record maximum energy density of 275.5 Wh kg-1 with a high working voltage of 1.07 V at 50 mA g-1. Meanwhile, under the synergistic effects of the conductive carbon cloth matrix, abundant hetero-interfaces and defects, as well as expanded interlayer spacing, the VMS@CC cathode displays superior rate capability and long-term cycling stability. Ex situ analyses demonstrate the VMS nanosheets cathode exhibits a Li+/Mg2+ co-insertion/extraction mechanism in MLIBs, following the in situ insertion of organic species in the hybrid electrolyte during the aging process. The fabricated flexible cathode herein provides a new insight into the construction of high-energy density cathodes for MLIBs.

3.
Anal Chem ; 96(29): 12074-12083, 2024 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-38981066

RESUMEN

Activatable probes with a higher signal-to-background ratio and accuracy are essential for monitoring liver cancer as well as intraoperative fluorescence navigation. However, the presence of only one biomarker is usually not sufficient to meet the high requirement of a signal-to-background ratio in cancer surveillance, leading to the risk of misdiagnosis. In this work, a dual-locked activation response probe, Si-NTR-LAP, for nitroreductase and leucine aminopeptidase was reported. This dual-locked probe provides better tumor recognition and a higher signal-to-noise ratio than that of single-locked probes (Si-LAP and Si-NTR). In both the subcutaneous tumor model and the more complex orthotopic hepatocellular carcinoma model, the probe was able to identify tumor tissue with high specificity and accurately differentiate the boundaries between tumor tissue and normal tissue. Therefore, the dual-locked probe may provide a new and practical strategy for applying to real patient tumor tissue samples.


Asunto(s)
Leucil Aminopeptidasa , Neoplasias Hepáticas , Nitrorreductasas , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/metabolismo , Humanos , Animales , Leucil Aminopeptidasa/metabolismo , Leucil Aminopeptidasa/análisis , Nitrorreductasas/metabolismo , Nitrorreductasas/análisis , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/metabolismo , Ratones , Colorantes Fluorescentes/química , Imagen Óptica
4.
Nanomicro Lett ; 16(1): 240, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38980475

RESUMEN

Single-atom materials have demonstrated attractive physicochemical characteristics. However, understanding the relationships between the coordination environment of single atoms and their properties at the atomic level remains a considerable challenge. Herein, a facile water-assisted carbonization approach is developed to fabricate well-defined asymmetrically coordinated Co-N4-O sites on biomass-derived carbon nanofiber (Co-N4-O/NCF) for electromagnetic wave (EMW) absorption. In such nanofiber, one atomically dispersed Co site is coordinated with four N atoms in the graphene basal plane and one oxygen atom in the axial direction. In-depth experimental and theoretical studies reveal that the axial Co-O coordination breaks the charge distribution symmetry in the planar porphyrin-like Co-N4 structure, leading to significantly enhanced dielectric polarization loss relevant to the planar Co-N4 sites. Importantly, the film based on Co-N4-O/NCF exhibits light weight, flexibility, excellent mechanical properties, great thermal insulating feature, and excellent EMW absorption with a reflection loss of - 45.82 dB along with an effective absorption bandwidth of 4.8 GHz. The findings of this work offer insight into the relationships between the single-atom coordination environment and the dielectric performance, and the proposed strategy can be extended toward the engineering of asymmetrically coordinated single atoms for various applications.

5.
Angew Chem Int Ed Engl ; : e202408218, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38923694

RESUMEN

Photorechargeable zinc ion batteries (PZIBs), which can directly harvest and store solar energy, are promising technologies for the development of a renewable energy society. However, the incompatibility requirement between narrow band gap and wide coverage has raised severe challenges for high-efficiency dual-functional photocathodes. Herein, half-metallic vanadium (III) oxide (V2O3) was first reported as a dual-functional photocathode for PZIBs. Theoretical and experimental results revealed its unique photoelectrical and zinc ion storage properties for capturing and storing solar energy. To this end, a synergistic protective etching strategy was developed to construct carbon superstructure-supported V2O3 nanospheres (V2O3@CSs). The half-metallic characteristics of V2O3, combined with the three-dimensional superstructure assembled by ultrathin carbon nanosheets, established rapid charge transfer networks and robust framework for efficient and stable solar-energy storage. Consequently, the V2O3@CSs photocathode delivered record zinc ion storage properties, including a photo-assisted discharge capacities of 463 mA ⋅ h ⋅ g-1 at 2.0 A ⋅ g-1 and long-term cycling stability over 3000 cycles. Notably, the PZIBs assembled using V2O3@CSs photocathodes could be photorecharged without an external circuit, exhibiting a high photo conversion efficiency (0.354 %) and photorecharge voltage (1.0 V). This study offered a promising direction for the direct capture and storage of solar energy.

6.
Artículo en Inglés | MEDLINE | ID: mdl-38837926

RESUMEN

Most deep learning approaches to comprehensive semantic modeling of 3D indoor spaces require costly dense annotations in the 3D domain. In this work, we explore a central 3D scene modeling task, namely, semantic scene reconstruction without using any 3D annotations. The key idea of our approach is to design a trainable model that employs both incomplete 3D reconstructions and their corresponding source RGB-D images, fusing cross-domain features into volumetric embeddings to predict complete 3D geometry, color, and semantics with only 2D labeling which can be either manual or machine-generated. Our key technical innovation is to leverage differentiable rendering of color and semantics to bridge 2D observations and unknown 3D space, using the observed RGB images and 2D semantics as supervision, respectively. We additionally develop a learning pipeline and corresponding method to enable learning from imperfect predicted 2D labels, which could be additionally acquired by synthesizing in an augmented set of virtual training views complementing the original real captures, enabling more efficient self-supervision loop for semantics. As a result, our end-to-end trainable solution jointly addresses geometry completion, colorization, and semantic mapping from limited RGB-D images, without relying on any 3D ground-truth information. Our method achieves state-of-the-art performance of semantic scene completion on two large-scale benchmark datasets MatterPort3D and ScanNet, surpasses baselines even with costly 3D annotations in predicting both geometry and semantics. To our knowledge, our method is also the first 2D-driven method addressing completion and semantic segmentation of real-world 3D scans simultaneously.

7.
Adv Mater ; 36(31): e2404828, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38781580

RESUMEN

High-performance fluorescent probes stand as indispensable tools in fluorescence-guided imaging, and are crucial for precise delineation of focal tissue while minimizing unnecessary removal of healthy tissue. Herein, machine-learning-assisted strategy to investigate the current available xanthene dyes is first proposed, and a quantitative prediction model to guide the rational synthesis of novel fluorescent molecules with the desired pH responsivity is constructed. Two novel Si─rhodamine derivatives are successfully achieved and the cathepsin/pH sequentially activated probe Si─rhodamine─cathepsin-pH (SiR─CTS-pH) is constructed. The results reveal that SiR─CTS-pH exhibits higher signal-to-noise ratio of fluorescence imaging, compared to single pH or cathepsin-activated probe. Moreover, SiR─CTS-pH shows strong differentiation abilities for tumor cells and tissues and accurately discriminates the complex hepatocellular carcinoma tissues from normal ones, indicating its significant application potential in clinical practice. Therefore, the continuous development of xanthene dyes and the rational design of superior fluorescent molecules through machine-learning-assisted model broaden the path and provide more advanced methods to researchers.


Asunto(s)
Catepsinas , Colorantes Fluorescentes , Aprendizaje Automático , Rodaminas , Rodaminas/química , Colorantes Fluorescentes/química , Humanos , Concentración de Iones de Hidrógeno , Catepsinas/metabolismo , Silicio/química , Imagen Óptica/métodos , Carcinoma Hepatocelular/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen
8.
Adv Mater ; 36(30): e2403531, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38733356

RESUMEN

Flexible perovskite solar cells (pero-SCs) have the potential to overturn the application scenario of silicon photovoltaic technology. However, their mechanical instability severely impedes their practical applicability, and the corresponding intrinsic degradation mechanism remains unclear. In this study, the degradation behavior of flexible pero-SCs is systematically analyzed under mechanical stress and it is observed that the structural failure first occurs in the polycrystal perovskite film, then extend to interfaces. To suppress the structural failure, pentaerythritol triacrylate, a crosslinked molecule with three stereoscopic crosslink sites, is employed to establish a 3D polymer network in both the interface and bulk perovskite. This network reduced the Young's modulus of the perovskite and simultaneously enhanced the interfacial toughness. As a result, the formation of cracks and delamination, which occur under a high mechanical stress, is significantly suppressed in the flexible pero-SC, which consequently retained 92% of its initial power conversion efficiency (PCE) after 20 000 bending cycles. Notably, the flexible device also shows a record PCE of 24.9% (certified 24.48%).

9.
New Phytol ; 242(6): 2787-2802, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38693568

RESUMEN

Root-knot nematodes (RKN; Meloidogyne species) are plant pathogens that introduce several effectors in their hosts to facilitate infection. The actual targets and functioning mechanism of these effectors largely remain unexplored. This study illuminates the role and interplay of the Meloidogyne javanica nematode effector ROS suppressor (Mj-NEROSs) within the host plant environment. Mj-NEROSs suppresses INF1-induced cell death as well as flg22-induced callose deposition and reactive oxygen species (ROS) production. A transcriptome analysis highlighted the downregulation of ROS-related genes upon Mj-NEROSs expression. NEROSs interacts with the plant Rieske's iron-sulfur protein (ISP) as shown by yeast-two-hybrid and bimolecular fluorescence complementation. Secreted from the subventral pharyngeal glands into giant cells, Mj-NEROSs localizes in the plastids where it interacts with ISP, subsequently altering electron transport rates and ROS production. Moreover, our results demonstrate that isp Arabidopsis thaliana mutants exhibit increased susceptibility to M. javanica, indicating ISP importance for plant immunity. The interaction of a nematode effector with a plastid protein highlights the possible role of root plastids in plant defense, prompting many questions on the details of this process.


Asunto(s)
Complejo III de Transporte de Electrones , Proteínas del Helminto , Proteínas Hierro-Azufre , Inmunidad de la Planta , Plastidios , Especies Reactivas de Oxígeno , Animales , Arabidopsis/parasitología , Arabidopsis/inmunología , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Complejo III de Transporte de Electrones/genética , Complejo III de Transporte de Electrones/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas del Helminto/metabolismo , Proteínas del Helminto/genética , Proteínas Hierro-Azufre/metabolismo , Proteínas Hierro-Azufre/genética , Mutación/genética , Enfermedades de las Plantas/parasitología , Enfermedades de las Plantas/inmunología , Plastidios/metabolismo , Unión Proteica , Especies Reactivas de Oxígeno/metabolismo , Tylenchoidea/genética , Tylenchoidea/patogenicidad
10.
Anal Methods ; 16(23): 3641-3645, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38812419

RESUMEN

Herein, we constructed a novel aminofluorene-based fluorescence probe (FEN-CE) for the detection of carboxylesterase (CE) in living cells by a ratiometric near-infrared (NIR) fluorescence signal. FEN-CE with NIR emission (650 nm) could be hydrolyzed specifically by CE and transformed to FENH with the release of the self-immolative group, which exhibited a red-shifted emission peak of 680 nm. In addition, FEN-CE showed high selectivity for CE and was successfully used in the detection of CE activity in living cells through its ratiometric NIR fluorescence signals.


Asunto(s)
Carboxilesterasa , Fluorenos , Colorantes Fluorescentes , Colorantes Fluorescentes/química , Carboxilesterasa/metabolismo , Carboxilesterasa/análisis , Humanos , Fluorenos/química , Espectroscopía Infrarroja Corta/métodos , Espectrometría de Fluorescencia/métodos , Células HeLa
11.
Proc Natl Acad Sci U S A ; 121(17): e2320777121, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38630719

RESUMEN

The hybrid electrolyzer coupled glycerol oxidation (GOR) with hydrogen evolution reaction (HER) is fascinating to simultaneously generate H2 and high value-added chemicals with low energy input, yet facing a challenge. Herein, Cu-based metal-organic frameworks (Cu-MOFs) are reported as model catalysts for both HER and GOR through doping of atomically dispersed precious and nonprecious metals. Remarkably, the HER activity of Ru-doped Cu-MOF outperformed a Pt/C catalyst, with its Faradaic efficiency for formate formation at 90% at a low potential of 1.40 V. Furthermore, the hybrid electrolyzer only needed 1.36 V to achieve 10 mA cm-2, 340 mV lower than that for splitting pure water. Theoretical calculations demonstrated that electronic interactions between the host and guest (doped) metals shifted downward the d-band centers (εd) of MOFs. This consequently lowered water adsorption and dissociation energy barriers and optimized hydrogen adsorption energy, leading to significantly enhanced HER activities. Meanwhile, the downshift of εd centers reduced energy barriers for rate-limiting step and the formation energy of OH*, synergistically enhancing the activity of MOFs for GOR. These findings offered an effective means for simultaneous productions of hydrogen fuel and high value-added chemicals using one hybrid electrolyzer with low energy input.

12.
PLoS One ; 19(4): e0299940, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38620031

RESUMEN

Injecting carbon dioxide is the most effective means of preventing and extinguishing fires in sealing hazardous areas, but the traditional method slowly and remotely injects carbon dioxide gas into the well after gasification on the ground, which is dependent on the complete mine pipe network without cooling effect. To inject liquid directly from the tank with vacuum interlayer and heat insulating powder for rapid inerting and cooling, a new approach using track mobile platform to go deep into the underground mine disaster area is proposed, so the liquid can be delivered to the nozzle at the end of DN40 large diameter pipe, and the continuous gasification jet can be realized. The experimental results show that: (1) The liquid volume in a tank of vacuum degree within 2.0 Pa and 200 mm interlayer reduced no more than 15.5% after 48 days; (2) Taking the pressure in the tank as the power source, because of environmental differences inside and outside the pipe after 100 m pressure holding delivery, the physical form of liquid and gas could be converted instantly; (3) The continuous discharge time without ice blocking for a tank full of 2 m3 liquid was about 10.5 min under 25 L dual mode nitrogen pressurization, which is 1/12 of injection time after ground gasification; (4) Based on the temperature decrease trend measured at different positions, the cooling characteristics on liquid gasification jet path are quantified, and the calculation formula of temperature changing with time on the center line of liquid gasification jet is obtained. Through this new approach, the integration of vacuum insulated storage, safe mobile transportation, and continuous and rapid release with large flow can be achieved for the liquid carbon dioxide.


Asunto(s)
Dióxido de Carbono , Incendios , Incendios/prevención & control , Nitrógeno , Calor , Frío
13.
Animals (Basel) ; 14(4)2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38396559

RESUMEN

Infections with Enterocytozoon hepatopenaei (EHP), infectious hypodermal and hematopoietic necrosis virus (IHHNV), and Decapod iridescent virus 1 (DIV1) pose significant challenges to the shrimp industry. Here, a melting curve-based triple real-time PCR assay based on the fluorescent dye Eva Green was established for the simultaneous detection of EHP, IHHNV, and DIV1. The assay showed high specificity, sensitivity, and reproducibility. A total of 190 clinical samples from Shandong, Jiangsu, Sichuan, Guangdong, and Hainan provinces in China were evaluated by the triple Eva Green real-time PCR assay. The positive rates of EHP, IHHNV, and DIV1 were 10.5%, 18.9%, and 44.2%, respectively. The samples were also evaluated by TaqMan qPCR assays for EHP, DIV1, and IHHNV, and the concordance rate was 100%. This illustrated that the newly developed triple Eva Green real-time PCR assay can provide an accurate method for the simultaneous detection of three shrimp pathogens.

14.
Angew Chem Int Ed Engl ; 63(12): e202318000, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38226788

RESUMEN

The kinetics and durability of conversion-based anodes greatly depend on the intrinsic stress regulating ability of the electrode materials, which has been significantly neglected. Herein, a stress dissipation strategy driven by multi-interface built-in electric fields (BEFs) and architected structure, is innovatively proposed to design ultrafast and long-term sodium ion storage anodes. Binary Mo/Fe sulfide heterostructured nanorods with multi-interface BEFs and staggered cantilever configuration are fabricated to prove our concept. Multi-physics simulations and experimental results confirm that the inner stress in multiple directions can be dissipated by the multi-interface BEFs at the micro-scale, and by the staggered cantilever structure at the macro-scale, respectively. As a result, our designed heterostructured nanorods anode exhibits superb rate capability (332.8 mAh g-1 at 10.0 A g-1 ) and durable cyclic stability over 900 cycles at 5.0 A g-1 , outperforming other metal chalcogenides. This proposed stress dissipation strategy offers a new insight for developing stable structures for conversion-based anodes.

15.
Small ; 20(26): e2309655, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38243851

RESUMEN

Bifunctional catalysts have inherent advantages in simplifying electrolysis devices and reducing electrolysis costs. Developing efficient and stable bifunctional catalysts is of great significance for industrial hydrogen production. Herein, a bifunctional catalyst, composed of nitrogen and sulfur co-doped carbon-coated trinickel disulfide (Ni3S2)/molybdenum dioxide (MoO2) nanowires (NiMoS@NSC NWs), is developed for seawater electrolysis. The designed NiMoS@NSC exhibited high activity in alkaline electrolyte with only 52 and 191 mV overpotential to attain 10 mA cm-2 for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively. Significantly, the electrolyzer (NiMoS@NSC||NiMoS@NSC) based on this bifunctional catalyst drove 100 mA cm-2 at only 1.71 V along with a robust stability over 100 h in alkaline seawater, which is superior to a platinum/nickel-iron layered double hydroxide couple (Pt||NiFe LDH). Theoretical calculations indicated that interfacial interactions between Ni3S2 and MoO2 rearranged the charge at interfaces and endowed Mo sites at the interfaces with Pt-like HER activity, while Ni sites on Ni3S2 surfaces at non-interfaces are the active centers for OER. Meanwhile, theoretical calculations and experimental results also demonstrated that interfacial interactions improved the electrical conductivity, boosting reaction kinetics for both HER and OER. This study presented a novel insight into the design of high-performance bifunctional electrocatalysts for seawater splitting.

16.
Angew Chem Int Ed Engl ; 63(7): e202316954, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38072899

RESUMEN

Despite the great success of perovskite photovoltaics in terms of device efficiency and stability using laboratory-scale spin-coating methods, the demand for high-throughput and cost-effective solutions remains unresolved and rarely reported because of the complicated nature of perovskite crystallization. In this work, we propose a stable precursor ink design strategy to control the solvent volatilization and perovskite crystallization to enable the wide speed window printing (0.3 to 18.0 m/min) of phase-pure FAPbI3 perovskite solar cells (pero-SCs) in ambient atmosphere. The FAPbI3 perovskite precursor ink uses volatile acetonitrile (ACN) as the main solvent with DMF and DMSO as coordination additives is beneficial to improve the ink stability, inhibit the coffee rings, and the complicated intermediate FAPbI3 phases, delivering high-quality pin-hole free and phase-pure FAPbI3 perovskite films with large-scale uniformity. Ultimately, small-area FAPbI3 pero-SCs (0.062 cm2 ) and large-area modules (15.64 cm2 ) achieved remarkable efficiencies of 24.32 % and 21.90 %, respectively, whereas the PCE of the devices can be maintained at 23.76 % when the printing speed increases to 18.0 m/min. Specifically, the unencapsulated device exhibits superior operational stability with T90 >1350 h. This work represents a step towards the scalable, cost-effective manufacturing of perovskite photovoltaics with both high performance and high throughput.

17.
J Colloid Interface Sci ; 657: 538-549, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38070339

RESUMEN

The exploitation of efficient, stable and cheap electrocatalyst for oxygen evolution reaction (OER) is very significant to the development of energy technology. In this study, Fe-based metal-organic frameworks (MIL-53(Fe)) self-supporting electrode with a 3D hierarchical open structure was developed through a semi-sacrificial strategy. The self-supporting electrode exhibits an excellent OER performance with an overpotential of 328 mV at 100 mA cm-2 in 1 M KOH, which is superior than that of IrO2 catalyst. Importantly, the optimized self-supporting electrode could operate at 100 mA cm-2 for 520 h without visible decrease in activity. It was also found that the structure of MIL-53(Fe) was in-situ self-reconstructed into oxyhydroxides during OER process. However, the 3D hierarchical open structure assembled with nano-microstructures kept well, which ensured the long-term stability of our self-supporting electrode for OER. Furthermore, density functional theory (DFT) calculations reveal that the FeOOH with rich oxygen vacancy transformed from MIL-53(Fe) plays a key role for the OER catalytic activity. And, the uninterrupted formation of oxygen vacancy during OER process ensures the continuous OER catalytic activity, which is the original source for the ultra-long stability of the self-supporting electrode toward OER. This work explores the way for the construction of efficient self-supporting oxygen electrodes based on MOFs.

18.
JACS Au ; 3(12): 3462-3472, 2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-38155649

RESUMEN

Enriching the palette of high-performance fluorescent dyes is vital to support the frontier of biomedical imaging. Although various rhodamine skeletons remain the premier type of small-molecule fluorophores due to the apparent high brightness and flexible modifiability, they still suffer from the inherent defect of small Stokes shift due to the nonideal fluorescence imaging signal-to-background ratio. Especially, the rising class of fluorescent dyes, sulfone-substituted xanthone, exhibits great potential, but low chemical stability is also pointed out as the problem. Molecular engineering of sulfone-xanthone to obtain a large Stokes shift and high stability is highly desired, but it is still scarce. Herein, we present the combination modification method for optimizing the performance of sulfone-xanthone. These redesigned fluorescent skeletons owned greatly improved stability and Stokes shift compared with the parent sulfone-rhodamine. To the proof of bioimaging capacity, annexin protein-targeted peptide LS301 was introduced to the most promising dyes, J-S-ARh, to form the tumor-targeted fluorescent probe, J-S-LS301. The resulting probe, J-S-LS301, can be an outstanding fluorescence tool for the orthotopic transplantation tumor model of hepatocellular carcinoma imaging and on-site pathological analysis. In summary, the combination method could serve as a basis for rational optimization of sulfone-xanthone. Overall, the chemistry reported here broadens the scope of accessible sulfone-xanthone functionality and, in turn, enables to facilitate the translation of biomedical research toward the clinical domain.

19.
Nanoscale ; 15(40): 16403-16412, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37791522

RESUMEN

Alkaline seawater electrolysis offers a way to generate hydrogen without carbon emissions. However, developing highly efficient catalysts that can sustain high performance and stability for the hydrogen evolution reaction (HER) in alkaline seawater is a formidable challenge. Here, a nanowire (NW) of a RuNi/MoC heterojunction embedded in N-doped carbon (RuNi/MoC@NC) was developed as a potent HER catalyst. The catalyst required only 21 mV at 10 mA cm-2 for HER in alkaline seawater, which surpasses 20% Pt/C. Moreover, using nickel foam (NF) as a catalyst carrier, an electrolyzer composed of RuNi/MoC@NC and nickel-iron layered double hydroxide (NiFe LDH) needed only 1.81 V at 500 mA cm-2 for full water splitting and showed long-term stability (over 500 h). Theoretical calculation revealed that the Ru and Ni sites in the catalyst had the optimal adsorption energy for hydrogen and water, respectively, which synergistically lowered the energy barrier for HER. This work offered an efficient method to design a highly effective HER catalyst for alkaline seawater splitting.

20.
ChemSusChem ; 16(24): e202300984, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-37670424

RESUMEN

In alkaline seawater electrolysis, the oxygen evolution reaction (OER) is greatly suppressed by the occurrence of electrode corrosion due to the formation of hypochlorite. Herein, a catalyst consisting of MoC nanowires modified with NiFe alloy nanoparticles (NiFe/MoC) on nickel foam (NF) is prepared. The optimized catalyst can deliver a large current density of 500 mA cm-2 at a very low overpotential of 366 mV in alkaline seawater, respectively, outperforming commercial IrO2 . Remarkably, an electrolyzer assembled with NiFe/MoC/NF as the anode and NiMoN/NF as the cathode only requires 1.77 V to drive a current density of 500 mA cm-2 for alkaline seawater electrolysis, as well as excellent stability. Theory calculation indicates that the initial activity of NiFe/MoC is attributed to increased electrical conductivity and decreased energy barrier for OER due to the introduction of Fe. We find that the change of the catalyst in the composition occurred after the stability test; however, the reconstructed catalyst has an energy barrier close to that of the pristine one, which is responsible for its excellent long-term stability. Our findings provide an efficient way to construct high-performance OER catalysts for alkaline seawater splitting.

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