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1.
Artigo em Inglês | MEDLINE | ID: mdl-39283967

RESUMO

The use of harmful halogenated or aromatic solvents such as chloroform (CF), chlorobenzene (CB), and o-xylene (o-XY) is one of the greatest barriers to the industrial-scale manufacturing of high-performance organic solar cells (OSCs). Therefore, it is necessary to eliminate the effects of these solvents to ensure practical feasibility of OSCs. We found that the anthracene-terminated polymer donor and small-molecule acceptor BO-4Cl had good solubility in 3-methylthiophene (3-MeT). There were no toxicity labels in the SDS and exposure control limits for 3-MeT. An overall power conversion efficiency of 16.87% was achieved by using 3-MeT as the solvent for solar cell fabrication, which was higher than that of the cells made from CF (16.18%) and o-XY (15.69%). The best OSC based on PM6:D18:L8-BO and fabricated with 3-MeT exhibited a high PCE of 18.13%, which is one of the highest values for cells fabricated from halogen-free solvents. These results indicate that 3-MeT is an eco-friendly and low-toxicity solvent for the sustainable fabrication of the OSC active layer.

2.
Inorg Chem ; 63(36): 16888-16896, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39196849

RESUMO

The development of advanced Pt-alternative anode electrocatalysts with high activity and reliable stability is critical to overcoming the technical challenges of direct methanol fuel cells. Here, we propose a robust bottom-up strategy for the spatial construction of mesoporous hollow carbon sphere (HCS)-embedded MXene architectures decorated with ultrafine Rh nanocrystals (Rh/HCS-MX) via stereoscopic coassembly reactions. The rational intercalation of HCS effectively separates the MXene nanowalls to achieve a rapid mass-transfer efficiency, while the intimate coupling of the hybrid carrier with Rh nanocrystals enables their electronic structure optimization, thus contributing to strong synergistic catalytic effects. Accordingly, the resulting Rh/HCS-MX architectures exhibit outstanding methanol electrooxidation properties in terms of large electrochemical active surface areas, high mass/specific activities, and good long-term stability, all of which are significantly superior to the traditional Rh/carbon black, Rh/HCS, and Rh/MXene as well as commercial Pt/carbon balck and Pd/carbon balck electrocatalysts.

3.
Int J Biol Macromol ; 277(Pt 3): 134495, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39111472

RESUMO

Anthracyclines belong to a class of anti-tumor antibiotics, and their severe cardiotoxicity significantly limits their clinical use. Exosomes play key roles in intercellular communication, characterized by high biocompatibility and specific tissue and organ homing effects. In this study, doxorubicin, an anthracycline anticancer drug widely used in clinical chemotherapy, was selected as a model drug. To address the significant cardiotoxicity associated with doxorubicin, tumor exosomes are utilized as drug carriers. The homing effect of autologous exosomes enhances drug uptake by tumor cells and reduces cardiotoxicity. To enhance the stability of exosomes, improve therapeutic effectiveness, and reduce toxic side effects, chitosan was utilized to modify the surface of exosomes. Chitosan has a specific anti-tumor effect because it can target the CD44 receptor of tumor stem cells and interact with tumor cells through charge adsorption. Through in vitro cell experiments, in vivo pharmacokinetic experiments, and an in situ ectopic nude mouse tumor model, the study demonstrated that chitosan-modified tumor exosomes significantly alleviated the severe cardiotoxicity of doxorubicin, while also showing remarkable anti-tumor efficacy. This study introduces a novel approach to reduce the adverse side effects of anthracycline chemotherapeutic drugs and presents a highly promising nanocarrier delivery system.


Assuntos
Cardiotoxicidade , Quitosana , Doxorrubicina , Exossomos , Quitosana/química , Quitosana/farmacologia , Exossomos/metabolismo , Animais , Cardiotoxicidade/prevenção & controle , Cardiotoxicidade/tratamento farmacológico , Humanos , Camundongos , Doxorrubicina/química , Doxorrubicina/farmacologia , Antraciclinas/química , Antraciclinas/efeitos adversos , Camundongos Nus , Linhagem Celular Tumoral , Portadores de Fármacos/química , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Chemistry ; : e202402430, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039628

RESUMO

Although MoS2 quantum dots with abundant edge sites have been regarded as promising eletrode materials for the hydrogen evolution reaction (HER), their electrocatalytic capacity still requires improvements in actual applications. Herein. we demonstrate a controllable and robust bottom-up approach to build 3D crosslinked graphene-Ti3C2Tx MXene frameworks decorated with MoS2 quantum dots (MQD/RGO-MX) via a convenient co-assembly process. The novel structural design gives the MQD/RGO-MX nanoarchitectures a series of superior textural attributes, including 3D interconnected networks, continuous meso- and macropores, well-dispersed quantum dots, ameliorative electronic configuration, and excellent electrical conductivity. Accordingly, the resulting hybrid nanoarchitectures express superior electrocatalytic properties in terms of a low onset potential of only 45 mV, a small Tafel slope of 61 mV dec-1 as well as a long service life towards the HER, which make it quite competitive against bare MoS2 quantum dots, MXene as well as binary MQD/RGO and MQD/MXene electrocatalysts.

5.
ACS Appl Mater Interfaces ; 16(19): 25422-25431, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695314

RESUMO

Flexible piezoresistive pressure sensors are garnering substantial attention, in line with advancements in biointegrated and wearable electronics. However, a significant portion of piezoresistive pressure sensors suffer from the trade-off between sensitivity and pressure range. Moreover, the current piezoresistive sensors generally rely on a rigid metallic electrode, severely deteriorating their long-term durability. Herein, a fully flexible piezoresistive sensor coupling polyurethane (PU) based electrode and active sensing element is proposed to circumvent the aforementioned problems. By rationally regulating the double-permeable conductive networks within the PU matrix, an elastomeric electrode and sensing element are implemented, respectively. The assembled heterostructured configurations enable impressive sensitivity up to 7.023 kPa-1, broad pressure detection (up to 420 kPa), an ultralow pressure sensing limit (0.1 Pa), and extraordinary operation stability over 80000 cyclic pressings along with fast response/relaxation times (60 ms/80 ms). Additionally, the fully flexible sensor is capable of both real-time detection of physiological signals and mimicking keyboards, implying its viability as a high-performance pressure sensor.

6.
Talanta ; 274: 126022, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574538

RESUMO

In this work, a highly sensitive lung cancer biomarkers detection probe was developed based on Ag and MXene co-functionalized magnetic microspheres. By using carboxyl magnetic microspheres as carrier, MXene was coated repeatedly by Poly (allylamine hydrochloride) (PAH) as interlayer adhesive, and silver particles grown on the surface of MXene in situ can efficiently improve the sensitivity of the probe. The detection of neuron specific enolase (NSE) is mainly through the formation of a specific complex between NSE antigen and antibody, and the release of antibody labeled with amino carbon quantum dots (CQDs) from the surface of Ag nanoparticles (AgNPs), so that the fluorescence is restored and "OFF-ON" is formed. The biosensor exhibits excellently wide linear range (0.0001-1500 ng/mL) and the limit of detection (LOD) is up to 0.03 pg/mL, which is superior to most tumor marker probes based on fluorescence mechanism. Furthermore, we constructed dual detection strategy for NSE and carcinoembryonic antigen (CEA) simultaneously.


Assuntos
Biomarcadores Tumorais , Antígeno Carcinoembrionário , Neoplasias Pulmonares , Microesferas , Fosfopiruvato Hidratase , Humanos , Biomarcadores Tumorais/análise , Técnicas Biossensoriais/métodos , Antígeno Carcinoembrionário/análise , Limite de Detecção , Neoplasias Pulmonares/diagnóstico , Nanopartículas Metálicas/química , Fosfopiruvato Hidratase/análise , Pontos Quânticos/química , Prata/química
7.
ACS Nano ; 18(15): 10341-10373, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38572836

RESUMO

Noble-metal nanocrystals have emerged as essential electrode materials for catalytic oxidation of organic small molecule fuels in direct liquid fuel cells (DLFCs). However, for large-scale commercialization of DLFCs, adopting cost-effective techniques and optimizing their structures using advanced matrices are crucial. Notably, noble metal-decorated porous carbon nanoarchitectures exhibit exceptional electrocatalytic performances owing to their three-dimensional cross-linked porous networks, large accessible surface areas, homogeneous dispersion (of noble metals), reliable structural stability, and outstanding electrical conductivity. Consequently, they can be utilized to develop next-generation anode catalysts for DLFCs. Considering the recent expeditious advancements in this field, this comprehensive review provides an overview of the current progress in noble metal-decorated porous carbon nanoarchitectures. This paper meticulously outlines the associated synthetic strategies, precise microstructure regulation techniques, and their application in electrooxidation of small organic molecules. Furthermore, the review highlights the research challenges and future opportunities in this prospective research field, offering valuable insights for both researchers and industry experts.

8.
Carbohydr Polym ; 329: 121780, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38286550

RESUMO

Our research aimed to enhance the oral bioavailability of doxorubicin hydrochloride (DOX·HCl) while minimizing the potential for myocardial toxicity. To achieve this goal, we developed a new method that utilizes a coating material to encapsulate the drug in liposomes, which can specifically target intestinal taurine transporter proteins. This coating material, TAU-CS, was created by combining taurine with chitosan. We characterized TAU-CS using various methods, including 1H NMR, FT-IR, and scanning electron microscopy (SEM). The resulting liposomes exhibited a regular spherical morphology, with a particle size of 195.7 nm, an encapsulation efficiency of 91.23 %, and a zeta potential of +11.65 mV. Under simulated gastrointestinal conditions, TAU-CS/LIP@DOX·HCl exhibited good stability and slow release. Pharmacokinetic studies revealed that, compared with DOX·HCl, TAU-CS/LIP@DOX·HCl had a relative bioavailability of 342 %. Intracellular uptake, immunofluorescence imaging, and permeation assays confirmed that the taurine transporter protein mediates the intestinal uptake of these liposomes. Our study suggested that liposomes coated with TAU-CS could serve as an effective oral delivery system and that targeting the taurine transporter protein shows promise in enhancing drug absorption.


Assuntos
Quitosana , Lipossomos , Quitosana/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Lipossomos/química , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Taurina/efeitos dos fármacos , Taurina/metabolismo
9.
ACS Appl Mater Interfaces ; 15(42): 49195-49203, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37843990

RESUMO

In this study, we demonstrate a facile soft chemistry strategy for the in situ growth of two-dimensional (2D) ultrathin PdMo bimetallene tightly coupled with Ti3C2Tx MXene nanosheets (PdMo/Ti3C2Tx) using a robust stereoassembly process. The 2D PdMo bimetallene offers numerous unsaturated Pd atoms and simultaneously induces combined bimetallic alloy and strain effects, while the Ti3C2Tx matrix effectively optimizes the electronic structure of PdMo bimetallene via a face-to-face interface interaction and guarantees exceptional electrical conductivity. As a consequence, the newly designed PdMo/Ti3C2Tx nanoarchitecture expresses remarkable electrocatalytic properties for the formic acid and methanol electro-oxidation, in terms of large electrochemically active surface areas, ultrahigh catalytic activity, strong antipoisoning ability, and dependable long-term stability, all of which are better than those of conventional Pd nanoparticle catalysts supported by Ti3C2Tx and carbon matrices.

10.
Dalton Trans ; 52(38): 13644-13652, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37702016

RESUMO

Currently, the state-of-the-art anode catalysts employed in direct methanol fuel cells (DMFCs) consist of nanosize Pt dispersed on a carbonaceous support; however, the relatively weak Pt-carbon interfacial interactions severely affect their overall electrocatalytic activity and service life. Herein, we demonstrate a convenient and robust stereo-assembly strategy for the efficient immobilization of ultrasmall Pt nanocrystals on 3D interweaving porous B-doped g-C3N4 nanosheet-graphene networks (Pt/BCN-G) by combining thermal annealing and solvothermal processes. This delicate configuration endowed the resulting hybrid nanoarchitecture with unusual textural merits, including 3D crosslinked porous skeletons, well-separated ultrathin nanosheets, rich B and N species, homogeneous Pt dispersion, stable heterointerface, and high electrical conductivity. Consequently, the 3D Pt/BCN-G nanoarchitecture with an optimized composition exhibited a large electrochemically active surface area of up to 121.2 m2 g-1, high mass activity of 1782.2 mA mg-1, superior poison tolerance, and excellent cycling stability towards the electrooxidation of methanol, all of which exceeded that of the reference Pt/graphene, Pt/BCN, Pt/carbon nanotube, Pt/carbon black, and Pt/g-C3N4 catalysts.

11.
Chem Sci ; 14(36): 9854-9862, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37736638

RESUMO

Two-dimensional (2D) Pd nanosheet-based catalysts have recently garnered widespread attention due to their high atom utilization efficiency. However, their catalytic ability and structural stability still require significant enhancement before they can be widely applied. In this study, we presented the rational design and controllable fabrication of a novel 2D/2D heterojunction, which consists of ultrathin Pd nanosheets (NSs) grown on the Ti3C2Tx MXene surface (Pd NSs/MXene). This heterostructure was achieved through a robust and convenient stereo-assembly strategy. The newly developed Pd NSs/MXene heterojunction not only provides numerous exposed active Pd atoms with an optimized electronic structure but also enables an intimate Pd/MXene interfacial interaction, ensuring a stable hybrid configuration. Consequently, the resulting Pd NSs/MXene heterojunction exhibits exceptional methanol oxidation properties. It possesses a large electrochemically active surface area, high mass and specific activities, and a long operating life, which are significantly superior to those of traditional Pd nanoparticle/carbon and Pd nanosheet/carbon catalysts. Theoretical simulations further reveal strong electronic interactions between the Pd nanosheet and MXene, which dramatically enhance the adsorption energy of the Pd component and simultaneously lower its d-band center. As a result, the Pd NSs/MXene heterojunction is less susceptible to CO poisoning. This work introduces a new 2D/2D heterojunction based on MXene and noble metallic materials and holds significance for the development of other novel heterojunctions, particularly within the realm of 2D material nanoarchitectonics.

12.
Dalton Trans ; 52(36): 12899-12908, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37642527

RESUMO

Photoinduced electron-separation and -transport processes are two independent crucial factors for determining the efficiency of photocatalytic hydrogen production. Herein, a sulfur vacancy defect-decorated CoSx@In2S3 (CoSx@VS-In2S3) core/shell heterojunction photocatalyst was synthesized via an in situ sulfidation method followed by a liquid-phase corrosion process. Photocatalytic hydrogen evolution experiments showed that the CoSx@VS-In2S3 nanohybrids delivered an attractive photocatalytic activity of 4.136 mmol h-1 g-1 under visible-light irradiation, which was 8.23 times higher than that of the pristine In2S3 samples. As expected, VS could enhance the charge-separation efficiency of In2S3 through rearranging the electrons of the In2S3 basal plane, in addition to improving the electron-transfer efficiency, as visually verified by transient absorption spectroscopy. Mechanism studies based on density functional theory calculations confirmed that the In atoms adjacent to VS played a key role in the translation, rotation, and transformation of electrons for water reduction. This scalable strategy focused on defect engineering paves a new avenue for the design and assembly of 2D core/shell heterostructures for efficient and robust water-splitting photocatalysts.

13.
Small ; 19(20): e2300402, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36808810

RESUMO

Design and preparation of an efficient and nonprecious cocatalysts, with structural features and functionality necessary for improving photocatalytic performance of semiconductors, remain a formidable challenge until now. Herein, for the first time, a novel CoP cocatalyst with single-atom phosphorus vacancies defects (CoP-Vp ) is synthesized and coupled with Cd0.5 Zn0.5 S to build CoP-Vp @Cd0.5 Zn0.5 S (CoP-Vp @CZS) heterojunctions photocatalysts via a liquid phase corrosion method following by an in suit growth process. The nanohybrids deliver an attractive photocatalytic hydrogen production activity of 2.05 mmol h-1 30 mg-1 under visible-light irradiation, which is 14.66 times higher than that of the pristine ZCS samples. As expected, CoP-Vp further enhances the charge-separation efficiency of ZCS, in addition to the improvement of the electron transfer efficiency, which is confirmed by the ultrafast spectroscopies. Mechanism studies based on density functional theory calculations verify that Co atoms adjacent with single-atom Vp play the key role in translation, rotation, and transformation of electrons for H2 O reduction. This scalable strategy focusing defect engineering provides a new insight into designing the highly active cocatalysts to boost the photocatalytic application.

14.
Hum Genomics ; 16(1): 64, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36457118

RESUMO

BACKGROUND: Aneuploidies are the most common chromosomal abnormality and the main genetic cause of adverse pregnancy outcomes. Since numerous studies have focused on common trisomies, relatively little is known about the association between phenotypic findings and rare autosomal aneuploidies (RAAs). We conducted a retrospective study of 48,904 cases for chromosomal microarray analysis in a large tertiary referral center and reported the overall frequencies, clinical manifestations, and outcomes of prenatal RAAs. RESULTS: A total of 90 RAAs were detected, of which 83 cases were mosaic trisomies and 7 were non-mosaic trisomies. Chromosomes 16, 22, and 9 were identified as the major chromosomes involving RAAs. The four predominant indications for prenatal diagnosis in our RAA cases were RAA-positive in noninvasive prenatal screening, advanced maternal age, ultrasound abnormalities, and high-risk for serum prenatal screening. Cardiovascular defects were the most frequently observed structural abnormalities, followed by musculoskeletal anomalies. Increased nuchal translucency and persistent left superior vena cava, the major soft marker abnormalities involved, were also observed in our RAA cases. Clinical outcomes were available for all RAAs, with 63 induced abortions and 27 live births recorded. CONCLUSIONS: Variable phenotypes and outcomes were observed, which were highly heterogeneous in cases of prenatal RAAs. Thus, a cautious and comprehensive strategy should be implemented during prenatal counseling for RAAs.


Assuntos
Resultado da Gravidez , Trissomia , Feminino , Gravidez , Humanos , Estudos Retrospectivos , Veia Cava Superior , Análise em Microsséries , Fenótipo , Aneuploidia , Cromossomos Humanos Par 16
15.
Inorg Chem ; 61(51): 21087-21094, 2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36516980

RESUMO

Along with the widespread utilization of hydrogen energy, the rise of highly active hydrogen evolution electrocatalysts with affordable costs presently becomes a substantial crux of this emerging domain. In this work, we demonstrate a feasible and convenient in situ seed-induced growth strategy for the construction of small-sized FeSe2 nanoparticles decorated on two-dimensional (2D) superthin Ti3C2Tx MXene sheets (FeSe2/Ti3C2Tx) through a manipulated bottom-up synthetic procedure. By virtue of the distinctive 0D/2D heterostructures, abundant exposed surface area, well-distributed FeSe2 catalytic centers, strong surface electronic coupling, and high electrical conductivity, the resultant FeSe2/Ti3C2Tx nanoarchitectures are endowed with a superior electrocatalytic hydrogen evolution capacity including a competitive onset potential of 89 mV, a favorable Tafel slope of 78 mV dec-1, and a long-period stability, significantly better than that of the pristine FeSe2 and Ti3C2Tx catalysts.

16.
Small ; 18(47): e2204557, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36216775

RESUMO

Defect engineering of transition metal dichalcogenides (TMDCs) is important for improving electrocatalytic hydrogen evolution reaction (HER) performance. Herein, a facile and scalable atomic-level di-defect strategy over thermodynamically stable VSe2 nanoflakes, yielding attractive improvements in the electrocatalytic HER performance over a wide electrolyte pH range is reported. The di-defect configuration with controllable spatial relation between single-atom (SA) V defects and single Se vacancy defects effectively triggers the electrocatalytic HER activity of the inert VSe2 basal plane. When employed as a cathode, this di-defects decorated VSe2 electrocatalyst requires overpotentials of 67.2, 72.3, and 122.3 mV to reach a HER current density of 10 mA cm-2 under acidic, alkaline, and neutral conditions, respectively, which are superior to most previously reported non-noble metal HER electrocatalysts. Theoretical calculations reveal that the reactive microenvironment consists of two adjacent SA Mo atoms with two surrounding symmetric Se vacancies, yielding optimal water dissociation and hydrogen desorption kinetics. This study provides a scalable strategy for improving the electrocatalytic activity of other TMDCs with inert atoms in the basal plane.

17.
Dalton Trans ; 51(44): 16982-16989, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36301151

RESUMO

The design and fabrication of non-Pt catalysts with excellent electrocatalytic performance toward methanol oxidation play a crucial role in the commercialization of direct methanol fuel cells (DMFCs). Herein, we propose a facile and robust strategy for the preparation of ultrafine Rh nanocrystals grown onto a boron and nitrogen codoped carbon support with a horn-shaped structure as Pt-alternative anode catalysts for DMFCs. The as-obtained hybrid nanoarchitecture possesses interesting structural features, including large specific surface area, numerous internal open pores, abundant B and N species, and homogeneous Rh dispersion. Benefiting from these superior properties, the resulting catalyst exhibits exceptional methanol oxidation performance with a large electrochemically active surface area of 182.4 m2 g-1, a high mass activity of 2350.5 mA mg-1, and good long-term durability, significantly outperforming Rh catalysts supported by conventional carbon supports and widely used Pt/carbon black and Pd/carbon black catalysts.

18.
IEEE Trans Biomed Circuits Syst ; 16(5): 867-881, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36070274

RESUMO

It has proved that the auscultation of respiratory sound has advantage in early respiratory diagnosis. Various methods have been raised to perform automatic respiratory sound analysis to reduce subjective diagnosis and physicians' workload. However, these methods highly rely on the quality of respiratory sound database. In this work, we have developed the first open-access paediatric respiratory sound database, SPRSound. The database consists of 2,683 records and 9,089 respiratory sound events from 292 participants. Accurate label is important to achieve a good prediction for adventitious respiratory sound classification problem. A custom-made sound label annotation software (SoundAnn) has been developed to perform sound editing, sound annotation, and quality assurance evaluation. A team of 11 experienced paediatric physicians is involved in the entire process to establish golden standard reference for the dataset. To verify the robustness and accuracy of the classification model, we have investigated the effects of different feature extraction methods and machine learning classifiers on the classification performance of our dataset. As such, we have achieved a score of 75.22%, 61.57%, 56.71%, and 37.84% for the four different classification challenges at the event level and record level.


Assuntos
Algoritmos , Sons Respiratórios , Humanos , Criança , Auscultação , Aprendizado de Máquina , Bases de Dados Factuais
19.
Dalton Trans ; 51(18): 7135-7141, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35466966

RESUMO

Hydrogen energy has attracted sustainable attention in the exploitation and application of advanced power-generator devices, and electrocatalysts for the hydrogen evolution reaction (HER) have been regarded as one of the core components in the current electrochemical hydrogen production systems. In this work, a facile and cost-effective bottom-up strategy is developed for the construction of 1D ultrafine cobalt selenide nanowires tangled with 2D Ti3C2Tx MXene nanosheets (CoSe NW/Ti3C2Tx) through an in situ stereo-assembly process. Such an architectural design endows the hybrid system not only with a large accessible surface for the rapid transportation of reactants, but also with numerous exposed CoSe edge sites, thereby generating substantial synergic coupling effects. The as-derived CoSe NW/Ti3C2Tx hybrid demonstrates competitive electrocatalytic properties toward the HER with a small onset potential of 84 mV, a low Tafel slope of 56 mV dec-1 and exceptional cycling performance, which are superior to those of bare CoSe and Ti3C2Tx materials. It is believed this promising nanoarchitecture may provide new possibilities for the design and construction of precious-metal-free electrocatalysts with high efficiency and great stability in the energy-conversion field.

20.
J Colloid Interface Sci ; 616: 781-790, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35247815

RESUMO

The development of high-efficiency methanol oxidation electrocatalysts with acceptable costs is central to the practical use of direct methanol fuel cell. In this work, a convenient interfacial engineering strategy is developed to the design and construction of quasi-one-dimensional worm-shaped palladium nanocrystals strongly coupled with positively-charged polyelectrolyte-modified Ti3C2Tx MXene (Pd NWs/PDDA-MX) via the direct electrostatic attractions. Because of the intriguing structural features including ultrathin-sheet nature, homogeneous Pd dispersion, numerous grain boundaries, strong electronic interaction, and high metallic conductivity, the as-fabricated Pd NWs/PDDA-MX hybrid shows superior electrocatalytic performance with a large electrochemically active surface area of 105.3 m2 g-1, a high mass activity of 1526.5 mA mg-1, and reliable long-term durability towards alkaline methanol oxidation reaction, far outperforming the commercial Pd nanoparticle/carbon catalysts. Density functional theory calculation further demonstrate that there are strong electronic interactions in the Pd nanoworm/Ti3C2Tx model with a depressed CO adsorption energy, thereby guaranteeing a stable interfacial contact as well as strong antitoxic ability.

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