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1.
J Fluoresc ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951306

RESUMO

The development of ecofriendly fabrication phenomenon is essential requirement for commercialization of non-fullerene acceptors. Recently, end-capped modeling is employed for computational design of five non-fullerene acceptors to elevate various photovoltaic properties. All new molecules are formulated by altering the peripheral acceptors of CH3-2F and DFT methodology is employed to explore the opto-electronic, morphological and charge transfer analysis. From the computational investigation, all reported molecules manifested red shifted absorption with remarkable reduced band gap. Among investigated molecules, FA1-FA3 evinced effectively decreased value of band gaps and designed molecules have low excitation energy justifying proficient charge transference. The lower values of binding energy of FA1 and FA2 suggest their facile exciton dissociation leading to improved charge mobility. By blending with J61 donor, FA4 have sufficiently enhanced value of VOC (1.72 eV) and fill factor (0.9228). Energy loss of the model (R) is 0.57 eV and statistical calculation demonstrate that all our modified molecules except FA3 has profoundly reduced energy loss compelling in its pivotal utilization. From accessible supportive outcomes of recent investigation, it is recommended that our modified chromophore exhibit remarkable noteworthy applications in solar cells for forthcoming innovations.

2.
Chem Rec ; 23(2): e202200149, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36408911

RESUMO

Recently, the growing demand for a renewable and sustainable fuel alternative is contingent on fuel cell technologies. Even though it is regarded as an environmentally sustainable method of generating fuel for immediate concerns, it must be enhanced to make it extraordinarily affordable, and environmentally sustainable. Hydrogen (H2 ) synthesis by electrochemical water splitting (ECWS) is considered one of the foremost potential prospective methods for renewable energy output and H2 society implementation. Existing massive H2 output is mostly reliant on the steaming reformation of carbon fuels that yield CO2 together with H2 and is a finite resource. ECWS is a viable, efficient, and contamination-free method for H2 evolution. Consequently, developing reliable and cost-effective technology for ECWS was a top priority for scientists around the globe. Utilizing renewable technologies to decrease total fuel utilization is crucial for H2 evolution. Capturing and transforming the fuel from the ambient through various renewable solutions for water splitting (WS) could effectively reduce the need for additional electricity. ECWS is among the foremost potential prospective methods for renewable energy output and the achievement of a H2 -based economy. For the overall water splitting (OWS), several transition-metal-based polyfunctional metal catalysts for both cathode and anode have been synthesized. Furthermore, the essential to the widespread adoption of such technology is the development of reduced-price, super functional electrocatalysts to substitute those, depending on metals. Many metal-premised electrocatalysts for both the anode and cathode have been designed for the WS process. The attributes of H2 and oxygen (O2 ) dynamics interactions on the electrodes of water electrolysis cells and the fundamental techniques for evaluating the achievement of electrocatalysts are outlined in this paper. Special emphasis is paid to their fabrication, electrocatalytic performance, durability, and measures for enhancing their efficiency. In addition, prospective ideas on metal-based WS electrocatalysts based on existing problems are presented. It is anticipated that this review will offer a straight direction toward the engineering and construction of novel polyfunctional electrocatalysts encompassing superior efficiency in a suitable WS technique.

3.
Chem Rec ; 23(1): e202200143, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36285706

RESUMO

The increasing demand for searching highly efficient and robust technologies in the context of sustainable energy production totally rely onto the cost-effective energy efficient production technologies. Solar power technology in this regard will perceived to be extensively employed in a variety of ways in the future ahead, in terms of the combustion of petroleum-based pollutants, CO2 reduction, heterogeneous photocatalysis, as well as the formation of unlimited and sustainable hydrogen gas production. Semiconductor-based photocatalysis is regarded as potentially sustainable solution in this context. g-C3 N4 is classified as non-metallic semiconductor to overcome this energy demand and enviromental challenges, because of its superior electronic configuration, which has a median band energy of around 2.7 eV, strong photocatalytic stability, and higher light performance. The photocatalytic performance of g-C3 N4 is perceived to be inadequate, owing to its small surface area along with high rate of charge recombination. However, various synthetic strategies were applied in order to incorporate g-C3 N4 with different guest materials to increase photocatalytic performance. After these fabrication approaches, the photocatalytic activity was enhanced owing to generation of photoinduced electrons and holes, by improving light absorption ability, and boosting surface area, which provides more space for photocatalytic reaction. In this review, various metals, non-metals, metals oxide, sulfides, and ferrites have been integrated with g-C3 N4 to form mono, bimetallic, heterojunction, Z-scheme, and S-scheme-based materials for boosting performance. Also, different varieties of g-C3 N4 were utilized for different aspects of photocatalytic application i. e., water reduction, water oxidation, CO2 reduction, and photodegradation of dye pollutants, etc. As a consequence, we have assembled a summary of the latest g-C3 N4 based materials, their uses in solar energy adaption, and proper management of the environment. This research will further well explain the detail of the mechanism of all these photocatalytic processes for the next steps, as well as the age number of new insights in order to overcome the current challenges.

4.
Inorg Chem ; 62(16): 6411-6420, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37036319

RESUMO

Developing cost-efficient and noble metal free electrocatalysts is vastly anticipated for the oxygen evolution reaction (OER). Therefore, in this study, to lift the thermodynamic and kinetic activity of the OER, we attempted to synthesize a bimetallic nickel and manganese-based zeolite imidazolate framework system in a fiber form. For this synthesis, a bottom-up approach has been followed through wet chemical analysis, and electrospinning was utilized for fiber formation. The resultant fiber has shown a lesser overpotential of 256 mV at a benchmarking current density of 10 mA cm-2 under 1 M KOH conditions. As expected, the attained Tafel slope and charge transfer resistance values are lesser. The observed results reveal that the synergism between the Ni and Mn nodes on the imidazolate framework successfully promotes the thermodynamic formation of *O and *OOH intermediates, which significantly helps to improve the faster OER kinetics at the electrode-electrolyte interface.

5.
Molecules ; 28(12)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37375293

RESUMO

Electrolytes are one of the most influential aspects determining the efficiency of electrochemical supercapacitors. Therefore, in this paper, we investigate the effect of introducing co-solvents of ester into ethylene carbonate (EC). The use of ester co-solvents in ethylene carbonate (EC) as an electrolyte for supercapacitors improves conductivity, electrochemical properties, and stability, allowing greater energy storage capacity and increased device durability. We synthesized extremely thin nanosheets of niobium silver sulfide using a hydrothermal process and mixed them with magnesium sulfate in different wt% ratios to produce Mg(NbAgS)x)(SO4)y. The synergistic effect of MgSO4 and NbS2 increased the storage capacity and energy density of the supercapattery. Multivalent ion storage in Mg(NbAgS)x(SO4)y enables the storage of a number of ions. The Mg(NbAgS)x)(SO4)y was directly deposited on a nickel foam substrate using a simple and innovative electrodeposition approach. The synthesized silver Mg(NbAgS)x)(SO4)y provided a maximum specific capacity of 2087 C/g at 2.0 A/g current density because of its substantial electrochemically active surface area and linked nanosheet channels which aid in ion transportation. The supercapattery was designed with Mg(NbAgS)x)(SO4)y and activated carbon (AC) achieved a high energy density of 79 Wh/kg in addition to its high power density of 420 W/kg. The supercapattery (Mg(NbAgS)x)(SO4)y//AC) was subjected to 15,000 consecutive cycles. The Coulombic efficiency of the device was 81% after 15,000 consecutive cycles while retaining a 78% capacity retention. This study reveals that the use of this novel electrode material (Mg(NbAgS)x(SO4)y) in ester-based electrolytes has great potential in supercapattery applications.

6.
Small ; 18(8): e2104387, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34716658

RESUMO

Metal-organic frameworks (MOFs) have potential applications in removing pollutants such as heavy metals, oils, and toxins from water. However, due to the intrinsic fragility of MOFs and their fine powder form, there are still technical barriers to their practical application such as blockage of pipes, difficulty in recovery, and potential environmental toxicity. Therefore, attention has focused on approaches to convert nanocrystalline MOFs into macroscopic materials to overcome these limitations. Recently, strategies for shaping MOFs into beads (0D), nanofibers (1D), membranes (2D), and gels/sponges (3D) with macrostructures are developed including direct mixing, in situ growth, or deposition of MOFs with polymers, cotton, foams or other porous substrates. In this review, successful strategies for the fabrication of macroscopic materials from MOFs and their applications in removing pollutants from water including adsorption, separation, and advanced oxidation processes, are discussed. The relationship between the macroscopic performance and the microstructure of materials, and how the range of 0D to 3D macroscopic materials can be used for water treatment are also outlined.


Assuntos
Poluentes Ambientais , Estruturas Metalorgânicas , Metais Pesados , Purificação da Água , Adsorção , Estruturas Metalorgânicas/química , Metais Pesados/química
7.
Small ; 18(33): e2203411, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35863911

RESUMO

Controlling the morphology, composition, and crystalline phase of mesoporous nonnoble metal catalysts is essential for improving their performance. Herein, well-defined P- and B-codoped NiFe alloy mesoporous nanospheres (NiFeB-P MNs) with an adjustable Ni/Fe ratio and large mesopores (11 nm) are synthesized via soft-template-based chemical reduction and a subsequent phosphine-vapor-based phosphidation process. Earth-abundant NiFe-based materials are considered promising electrocatalysts for the oxygen evolution reaction (OER) because of their low cost and high intrinsic catalytic activity. The resulting NiFeB-P MNs exhibit a low OER overpotential of 252 mV at 10 mA cm-2 , which is significantly smaller than that of B-doped NiFe MNs (274 mV) and commercial RuO2 (269 mV) in alkaline electrolytes. Thus, this work highlights the practicality of designing mesoporous nonnoble metal structures and the importance of incorporating P in metallic-B-based alloys to modify their electronic structure for enhancing their intrinsic activity.

8.
Small ; 18(26): e2107571, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35620959

RESUMO

The integration of nanoarchitectonics and hydrogel into conventional biosensing platforms offers the opportunities to design physically and chemically controlled and optimized soft structures with superior biocompatibility, better immobilization of biomolecules, and specific and sensitive biosensor design. The physical and chemical properties of 3D hydrogel structures can be modified by integrating with nanostructures. Such modifications can enhance their responsiveness to mechanical, optical, thermal, magnetic, and electric stimuli, which in turn can enhance the practicality of biosensors in clinical settings. This review describes the synthesis and kinetics of gel networks and exploitation of nanostructure-integrated hydrogels in biosensing. With an emphasis on different integration strategies of hydrogel with nanostructures, this review highlights the importance of hydrogel nanostructures as one of the most favorable candidates for developing ultrasensitive biosensors. Moreover, hydrogel nanoarchitectonics are also portrayed as a promising candidate for fabricating next-generation robust biosensors.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Hidrogéis/química , Nanoestruturas/química
9.
Chem Rec ; 22(12): e202200097, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36103617

RESUMO

Use of MXenes (Ti3 C2 Tx ), which belongs to the family of two-dimensional transition metal nitrides and carbides by encompassing unique combination of metallic conductivity and hydrophilicity, is receiving tremendous attention, since its discovery as energy material in 2011. Owing to its precursor selective chemical etching, and unique intrinsic characteristics, the MXene surface properties are further classified into highly chemically active compound, which further produced different surface functional groups i. e., oxygen, fluorine or hydroxyl groups. However, the role of surface functional groups doesn't not only have a significant impact onto its electrochemical and hydrophilic characteristics (i. e., ion adsorption/diffusion), but also imparting a noteworthy effect onto its conductivity, work function, electronic structure and properties. Henceforth, such kind of inherent chemical nature, robust electrochemistry and high hydrophilicity ultimately increasing the MXene application as a most propitious material for overall environment-remediation, electrocatalytic sensors, energy conversion and storage application. Moreover, it is well documented that the role of MXenes in all kinds of research fields is still on a progress stage for their further improvement, which is not sufficiently summarized in literature till now. The present review article is intended to critically discuss the different chemical aptitudes and the diversity of MXenes and its derivates (i. e., hybrid composites) in all aforesaid application with special emphasis onto the improvement of its surface characteristics for the multidimensional application. However, this review article is anticipated to endorse MXenes and its derivates hybrid configuration, which is discussed in detail for emerging environmental decontamination, electrochemical use, and pollutant detection via electrocatalytic sensors, photocatalysis, along with membrane distillation and the adsorption application. Finally, it is expected, that this review article will open up new window for the effective use of MXene in a broad range of environmental remediation, energy conversion and storage application as a novel, robust, multidimensional and more proficient materials.

10.
Chem Rec ; 22(7): e202100310, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35138017

RESUMO

Being one of the foremost enticing and intriguing innovations, heterogeneous photocatalysis has also been used to effectively gather, transform, and conserve sustainable sun's radiation for the production of efficient and clean fossil energy as well as a wide range of ecological implications. The generation of solar fuel-based water splitting and CO2 photoreduction is excellent for generating alternative resources and reducing global warming. Developing an inexpensive photocatalyst can effectively split water into hydrogen (H2 ), oxygen (O2 ) sources, and carbon dioxide (CO2 ) into fuel sources, which is a crucial problem in photocatalysis. The metal-free g-C3 N4 photocatalyst has a high solar fuel generation potential. This review covers the most recent advancements in g-C3 N4 preparation, including innovative design concepts and new synthesis methods, and novel ideas for expanding the light absorption of pure g-C3 N4 for photocatalytic application. Similarly, the main issue concerning research and prospects in photocatalysts based g-C3 N4 was also discussed. The current dissertation provides an overview of comprehensive understanding of the exploitation of the extraordinary systemic and characteristics, as well as the fabrication processes and uses of g-C3 N4 .

11.
Environ Res ; 210: 112909, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35157915

RESUMO

The design of high-performance electrode materials with excellent desalination ability has always been a research goal for efficient capacitive deionization (CDI). Herein, a hybrid architecture with Cu/Cu2O nanospheres anchored on porous carbon nanosheets (Cu/Cu2O/C) was first synthesized by pyrolyzing a two-dimensional (2D) Cu-based metal-organic framework and then evaluated as a cathode for hybrid CDI. The as-prepared Cu/Cu2O/C exhibits a hierarchically porous structure with a high specific surface area of 305 m2 g-1 and large pore volume of 0.55 cm3 g-1, which is favorable to accelerating ion migration and diffusion. The porous carbon nanosheet matrix with enhanced conductivity will facilitate the Faradaic reactions of Cu/Cu2O nanospheres during the desalination process. The Cu/Cu2O/C hybrid architecture displays a high specific capacitance of 142.5 F g-1 at a scan rate of 2 mV s-1 in 1 M NaCl solution. The hybrid CDI constructed using the Cu/Cu2O/C cathode and a commercial activated carbon anode exhibits a high desalination capacity of 16.4 mg g-1 at an operation voltage of 1.2 V in 500 mg L-1 NaCl solution. Additionally, the hybrid CDI exhibits a good cycling stability with 18.3% decay in the desalination capacity after 20 electrosorption-desorption cycles. Thus, the Cu/Cu2O/C composite is expected to be a promising cathode material for hybrid CDI.

12.
Environ Res ; 212(Pt C): 113331, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35472462

RESUMO

Mn-based oxides are efficient pseudocapacitive electrode materials and have been investigated for capacitive deionization (CDI). However, their poor conductivity seriously affects their desalination performance. In this work, polyaniline coated Mn2O3 nanorods (PANI/Mn2O3) are synthesized by oxidizing a Mn-based metal organic framework (MOF) and subsequent in-situ chemical polymerization. The polyaniline not only acts as a conductive network for faradaic reactions of Mn2O3, but also enhances the desalination rate. PANI/Mn2O3 has a specific capacitance of 87 F g-1 (at 1 A g-1), superior to that of Mn2O3 nanorod (52 F g-1 at 1 A g-1). The hybrid CDI cell constructed with a PANI/Mn2O3 cathode and an active carbon anode shows a high desalination capacity of 21.6 mg g-1, superior recyclability with only 11.3% desalination capacity decay after 30 desalination cycles and fast desalination rate of 2.2 mg g-1 min-1. PANI/Mn2O3 is a potential candidate for high performance CDI applications.

13.
Molecules ; 27(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36080500

RESUMO

Novel cyano-benzylidene xanthene derivatives were synthesized using one-pot and condensation reactions. A diprotic Brønsted acid (i.e., oxalic acid) was used as an effective catalyst for the promotion of the synthesis process of the new starting xanthene-aldehyde compound. Different xanthene concentrations (ca. 0.1-2.0 mM) were applied as corrosion inhibitors to control the alkaline uniform corrosion of aluminum. Measurements were conducted in 1.0 M NaOH solution using Tafel extrapolation and linear polarization resistance (LPR) methods. The investigated xanthenes acted as mixed-type inhibitors that primarily affect the anodic process. Their inhibition efficiency values were enhanced with inhibitor concentration, and varied according to their chemical structures. At a concentration of 2.0 mM, the best-performing studied xanthene derivative recorded maximum inhibition efficiency values of 98.9% (calculated via the Tafel extrapolation method) and 98.4% (estimated via the LPR method). Scanning electron microscopy (SEM) was used to examine the morphology of the corroded and inhibited aluminum surfaces, revealing strong inhibitory action of each studied compound. High-resolution X-ray photoelectron spectroscopy (XPS) profiles validated the inhibitor compounds' adsorption on the Al surface. Density functional theory (DFT) and Monte Carlo simulations were applied to investigate the distinction of the anticorrosive behavior among the studied xanthenes toward the Al (111) surface. The non-planarity of xanthenes and the presence of the nitrile group were the key players in the adsorption process. A match between the experimental and theoretical findings was evidenced.


Assuntos
Alumínio , Xantenos , Ácidos/química , Adsorção , Alumínio/química , Corrosão , Xantenos/química
14.
Molecules ; 26(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34684893

RESUMO

The present work aimed to assess six diaryl sulfide derivatives as potential corrosion inhibitors. These derivatives were compared with dapsone (4,4'-diaminodiphenyl sulfone), a common leprosy antibiotic that has been shown to resist the corrosion of mild steel in acidic media with a corrosion efficiency exceeding 90%. Since all the studied compounds possess a common molecular backbone (diphenyl sulfide), dapsone was taken as the reference compound to evaluate the efficiency of the remainder. In this respect, two structural factors were examined, namely, (i) the effect of replacement of the S-atom of diaryl sulfide by SO or SO2 group, (ii) the effect of the introduction of an electron-withdrawing or an electron-donating group in the aryl moiety. Two computational chemical approaches were used to achieve the objectives: the density functional theory (DFT) and the Monto Carlo (MC) simulation. First, B3LYP/6-311+G(d,p) model chemistry was employed to calculate quantum chemical descriptors of the studied molecules and their geometric and electronic structures. Additionally, the mode of adsorption of the tested molecules was investigated using MC simulation. In general, the adsorption process was favorable for molecules with a lower dipole moment. Based on the adsorption energy results, five diaryl sulfide derivatives are expected to act as better corrosion inhibitors than dapsone.

15.
J Biol Chem ; 293(16): 5755-5765, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29475948

RESUMO

Chromosome alignment and segregation during mitosis require kinetochore-microtubule (kMT) attachments that are mediated by the molecular motor dynein and the kMT-binding complex Ndc80. The Rod-ZW10-Zwilch (RZZ) complex is central to this coordination as it has an important role in dynein recruitment and has recently been reported to have a key function in the regulation of stable kMT attachments in Caenorhabditis elegans besides its role in activating the spindle assembly checkpoint (SAC). However, the mechanism by which these protein complexes control kMT attachments to drive chromosome motility during early mitosis is still unclear. Here, using in vitro total internal reflection fluorescence microscopy, we observed that higher concentrations of Ndc80 inhibited dynein binding to MTs, providing evidence that Ndc80 and dynein antagonize each other's function. High-resolution microscopy and siRNA-mediated functional disruption revealed that severe defects in chromosome alignment induced by depletion of dynein or the dynein adapter Spindly are rescued by codepletion of the RZZ component Rod in human cells. Interestingly, rescue of the chromosome alignment defects was independent of Rod function in SAC activation and was accompanied by a remarkable restoration of stable kMT attachments. Furthermore, the chromosome alignment rescue depended on the plus-end-directed motility of centromere protein E (CENP-E) because cells codepleted of CENP-E, Rod, and dynein could not establish stable kMT attachments or align their chromosomes properly. Our findings support the idea that dynein may control the function of the Ndc80 complex in stabilizing kMT attachments directly by interfering with Ndc80-MT binding or indirectly by controlling the Rod-mediated inhibition of Ndc80.


Assuntos
Dineínas/metabolismo , Cinetocoros/metabolismo , Microtúbulos/metabolismo , Mitose , Proteínas Nucleares/metabolismo , Proteínas do Citoesqueleto , Células HeLa , Humanos , Cinetocoros/ultraestrutura , Microtúbulos/ultraestrutura , Ligação Proteica
17.
Blood Cancer J ; 14(1): 42, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453907

RESUMO

As key developmental regulators, HOX cluster genes have varied and context-specific roles in normal and malignant hematopoiesis. A complex interaction of transcription factors, epigenetic regulators, long non-coding RNAs and chromatin structural changes orchestrate HOX expression in leukemia cells. In this review we summarize molecular mechanisms underlying HOX regulation in clinical subsets of AML, with a focus on NPM1 mutated (NPM1mut) AML comprising a third of all AML patients. While the leukemia initiating function of the NPM1 mutation is clearly dependent on HOX activity, the favorable treatment responses in these patients with upregulation of HOX cluster genes is a poorly understood paradoxical observation. Recent data confirm FOXM1 as a suppressor of HOX activity and a well-known binding partner of NPM suggesting that FOXM1 inactivation may mediate the effect of cytoplasmic NPM on HOX upregulation. Conversely the residual nuclear fraction of mutant NPM has also been recently shown to have chromatin modifying effects permissive to HOX expression. Recent identification of the menin-MLL interaction as a critical vulnerability of HOX-dependent AML has fueled the development of menin inhibitors that are clinically active in NPM1 and MLL rearranged AML despite inconsistent suppression of the HOX locus. Insights into context-specific regulation of HOX in AML may provide a solid foundation for targeting this common vulnerability across several major AML subtypes.


Assuntos
Proteínas de Homeodomínio , Leucemia Mieloide Aguda , Humanos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Leucemia Mieloide Aguda/patologia , Proteínas Nucleares/genética , Nucleofosmina , Regulação Leucêmica da Expressão Gênica , Fatores de Transcrição/genética , Cromatina , Expressão Gênica
18.
J Colloid Interface Sci ; 664: 178-185, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38460382

RESUMO

H2 produced through hydrogen evolution reaction (HER) is a shining star in the field of clean energy. Significant efforts have been dedicated to develop efficient and stable electrocatalysts to reduce the energy barrier and accelerate the kinetics of Hydrogen evolution reaction (HER) under various environments. Herein, we propose a strategy to accelerate the kinetics of HER under acid and alkaline environments by combining heterostructure engineering with defect engineering. We have successfully synthesized a series of WS2/WO3-x heterostructured catalysts, accompanied with substantial oxygen vacancies using a two-step synthesis method. With the partially sulfurization of WO3-x, the heterojunction interface of WS2 and WO3-x was formed along with the appearance of oxygen vacancies, which can facilitate the migration of electrons. The heterostructured catalyst enriched with oxygen vacancies (defined as WS2/WO3-x-2) demonstrates superior HER performance in acidic and alkaline electrolytes. At a current density of 10 mA cm-2, the WS2/WO3-x-2 heterostructured catalyst manifests an overpotential of 120 mV in the acidic electrolytes and a slightly higher overpotential of 150 mV in an alkaline environment. The overpotentials offer an improvement compared to reported W-based catalysts in terms of HER performance. This work provides guiding significance on the design of heterostructured catalysts with promising performance for HER in acidic and alkaline environments.

19.
ChemSusChem ; : e202400056, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38525654

RESUMO

The development of low-cost transition metal compounds with high-performance for efficient oxygen evolution reaction (OER) is of great significance in promoting the development of electrocatalysis. In this study, a Ce-doped Ni3S4 catalyst (Ce0.2-Ni3S4) was synthesized through a one-step solvothermal method, where the doped rare earth element Ce induced the transformation of NiS to Ni3S4. The Ce0.2-Ni3S4 catalyst exhibited excellent OER performance in 1 M KOH. At a current density of 10 mA cm-2, it showed a low overpotential of 230 mV and a low Tafel slope of 52.39 mV dec-1. Long-term OER tests at the same potential lasted for 24 h without significant loss of current density. This work introduces a novel method of Ce element doping for modifying transition metal sulfides, providing new insights into the effective utilization of rare earth elements in the field of electrochemistry. It creates more chances for the progress of highly efficient catalysts for efficient OER, contributing to the advancement of electrocatalysis.

20.
J Mol Model ; 30(6): 190, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809306

RESUMO

CONTEXT: For the advancement in fields of organic and perovskite solar cells, various techniques of structural alterations are being employed on previously reported chromophores. In this study, the end-capped engineering is carried out on DBT-4F (R) by modifying terminal acceptors to improve optoelectronic and photovoltaic attributes. Seven molecules (AD1-AD7) are modeled using different push-pull acceptors. DFT/B3LYP/6-31G along with its time-dependent approach (TD-DFT) are on a payroll to investigate ground state geometries, absorption maxima (λmax), energy gap (Eg), excitation energy (Ex), internal reorganization energy, light harvesting efficiency (LHE), dielectric constant, open circuit voltage (VOC), fill factor (FF), etc. of OSCs. AD1 displayed the lowest band gap (1.76 eV), highest λmax (876 nm), lowest Ex (1.41 eV), and lowest binding energy (0.21 eV). Among various calculated parameters, all of the sketched molecules demonstrated greater dielectric constant when compared to R. The highest dielectric constant was exhibited by AD3 (56.26). AD5 exhibited maximum LHE (0.9980). Lower reorganization energies demonstrated improved charge mobility. AD5 and AD7 (1.63 and 1.68 eV) have higher values of VOC than R (1.51 eV). All novel molecules having outperforming attributes will be better candidates to enhance the efficacy of OSCs for future use. METHODS: Precisely, a DFT and TD-DFT analysis on all of the proposed organic molecules were conducted, using the functional MPW1PW91 at 6-31G (d,p) basis set to examine their optoelectronic aspects, additionally the solvent-state computations were studied with a TD-SCF simulation. For all these simulations, Guassian 09 and GuassView 5.0 were employed. Moreover, the Origin 6.0, Multiwfn 3.8, and PyMOlyze 1.1 software were utilized for the visual depiction of the graphs of absorption, TDM, and DOS, respectively of the studied molecules. A number of crucial aspects such as FMOs, bandgaps, light-harvesting efficiency, electrostatic potential, dipole moment, ionization potential, open-circuit voltage, fill factor, binding energy, interaction coefficient, chemical hardness-softness, and electrophilicity index were also investigated for the studied molecules.

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