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1.
Cell ; 175(2): 347-359.e14, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30290141

RESUMO

We analyze whole-genome sequencing data from 141,431 Chinese women generated for non-invasive prenatal testing (NIPT). We use these data to characterize the population genetic structure and to investigate genetic associations with maternal and infectious traits. We show that the present day distribution of alleles is a function of both ancient migration and very recent population movements. We reveal novel phenotype-genotype associations, including several replicated associations with height and BMI, an association between maternal age and EMB, and between twin pregnancy and NRG1. Finally, we identify a unique pattern of circulating viral DNA in plasma with high prevalence of hepatitis B and other clinically relevant maternal infections. A GWAS for viral infections identifies an exceptionally strong association between integrated herpesvirus 6 and MOV10L1, which affects piwi-interacting RNA (piRNA) processing and PIWI protein function. These findings demonstrate the great value and potential of accumulating NIPT data for worldwide medical and genetic analyses.


Assuntos
Povo Asiático/genética , Diagnóstico Pré-Natal/métodos , Adulto , Alelos , China , DNA/genética , Etnicidade/genética , Feminino , Frequência do Gene/genética , Testes Genéticos , Variação Genética/genética , Genética Populacional/métodos , Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Migração Humana , Humanos , Gravidez , Análise de Sequência de DNA
2.
Genome Res ; 31(7): 1150-1158, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34155038

RESUMO

Protein-truncating variants (PTVs) have important impacts on phenotype diversity and disease. However, their population genetics characteristics in more globally diverse populations are not well defined. Here, we describe patterns of PTVs in 1320 genes sequenced in 10,539 healthy controls and 9434 patients with psoriasis, all of Han Chinese ancestry. We identify 8720 PTVs, of which 77% are novel, and estimate 88% of all PTVs are deleterious and subject to purifying selection. Furthermore, we show that individuals with psoriasis have a significantly higher burden of PTVs compared to controls (P = 0.02). Finally, we identified 18 PTVs in 14 genes with unusually high levels of population differentiation, consistent with the action of local adaptation. Our study provides insights into patterns and consequences of PTVs.

3.
Small ; : e2404000, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809060

RESUMO

Multifunctional electrocatalysts for hydrogen evolution reaction (HER), hydrogen oxidation reaction (HOR), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) have broad application prospects; However, realization of such kinds of materials remain difficulties because it requires the materials to have not only unique electronic properties, but multiple active centers to deal with different reactions. Here, employing density functional theory (DFT) computations, it is demonstrated that by decorating the Janus-type 2D transition metal dichalcogenide (TMD) of TaSSe with the single atoms, the materials can achieve multifunctionality to catalyze the ORR/OER/HER/HOR. Out of sixteen catalytic systems, Pt-VS (i.e., Pt atom embedded in the sulfur vacancy), Pd-VSe, and Pt-VSe@TaSSe are promising multifunctional catalysts with superior stability. Among them, the Pt-VS@TaSSe catalyst exhibits the highest activity with theoretical overpotentials ηORR = 0.40 V, ηOER = 0.39 V, and ηHER/HOR = 0.07 V, respectively, better than the traditional Pt (111), IrO2 (110). The interplays between the catalyst and the reaction intermediate over the course of the reaction are then systematically investigated. Generally, this study presents a viable approach for the design and development of advanced multifunctional electrocatalysts. It enriches the application of Janus, a new 2D material, in electrochemical energy storage and conversion technology.

4.
Planta ; 260(1): 33, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896325

RESUMO

MAIN CONCLUSION: γ-Aminobutyric acid alleviates acid-aluminum toxicity to roots associated with enhanced antioxidant metabolism as well as accumulation and transportation of citric and malic acids. Aluminum (Al) toxicity has become the main limiting factor for crop growth and development in acidic soils and is further being aggravated worldwide due to continuous industrial pollution. The current study was designed to examine effects of GABA priming on alleviating acid-Al toxicity in terms of root growth, antioxidant defense, citrate and malate metabolisms, and extensive metabolites remodeling in roots under acidic conditions. Thirty-seven-day-old creeping bentgrass (Agrostis stolonifera) plants were used as test materials. Roots priming with or without 0.5 mM GABA for 3 days were cultivated in standard nutrient solution for 15 days as control or subjected to nutrient solution containing 5 mM AlCl3·6H2O for 15 days as acid-Al stress treatment. Roots were sampled for determinations of root characteristics, physiological and biochemical parameters, and metabolomics. GABA priming significantly alleviated acid-Al-induced root growth inhibition and oxidative damage, despite it promoted the accumulation of Al in roots. Analysis of metabolomics showed that GABA priming significantly increased accumulations of organic acids, amino acids, carbohydrates, and other metabolites in roots under acid-Al stress. In addition, GABA priming also significantly up-regulated key genes related to accumulation and transportation of malic and citric acids in roots under acid-Al stress. GABA-regulated metabolites participated in tricarboxylic acid cycle, GABA shunt, antioxidant defense system, and lipid metabolism, which played positive roles in reactive oxygen species scavenging, energy conversion, osmotic adjustment, and Al ion chelation in roots.


Assuntos
Agrostis , Alumínio , Antioxidantes , Malatos , Raízes de Plantas , Ácido gama-Aminobutírico , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Antioxidantes/metabolismo , Ácido gama-Aminobutírico/metabolismo , Alumínio/toxicidade , Agrostis/efeitos dos fármacos , Agrostis/metabolismo , Agrostis/fisiologia , Malatos/metabolismo , Ácido Cítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos
5.
Mol Ecol ; 33(2): e17205, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37971141

RESUMO

Genomic studies of species threatened by extinction are providing crucial information about evolutionary mechanisms and genetic consequences of population declines and bottlenecks. However, to understand how species avoid the extinction vortex, insights can be drawn by studying species that thrive despite past declines. Here, we studied the population genomics of the muskox (Ovibos moschatus), an Ice Age relict that was at the brink of extinction for thousands of years at the end of the Pleistocene yet appears to be thriving today. We analysed 108 whole genomes, including present-day individuals representing the current native range of both muskox subspecies, the white-faced and the barren-ground muskox (O. moschatus wardi and O. moschatus moschatus) and a ~21,000-year-old ancient individual from Siberia. We found that the muskox' demographic history was profoundly shaped by past climate changes and post-glacial re-colonizations. In particular, the white-faced muskox has the lowest genome-wide heterozygosity recorded in an ungulate. Yet, there is no evidence of inbreeding depression in native muskox populations. We hypothesize that this can be explained by the effect of long-term gradual population declines that allowed for purging of strongly deleterious mutations. This study provides insights into how species with a history of population bottlenecks, small population sizes and low genetic diversity survive against all odds.


Assuntos
Metagenômica , Resiliência Psicológica , Humanos , Animais , Recém-Nascido , Evolução Biológica , Genômica , Ruminantes/genética , Variação Genética/genética
6.
Langmuir ; 40(27): 14099-14109, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38920408

RESUMO

With the wide application of lithium-ion batteries (LIBs) in different fields, safety accidents occur frequently. Therefore, it is necessary to monitor the thermal runaway gas for an early warning. In this article, the adsorption properties of the characteristic gases of LIBs thermal runaway gases are studied by density functional theory (DFT). The adsorption structure of TM (Co/Rh/Ir)-decorated HfS2 (TM@HfS2) is established, and its adsorption properties for C2H4, CH4, and CO are studied. The adsorption energy, charge transfer, band, DOS, charge difference density, work function, and recovery time are discussed in detail. The results show that Ir@HfS2 has the strongest adsorption performance for C2H4 and CO, so C2H4 and CO can be stably adsorbed on the surface of the Ir@HfS2 monolayer. The adsorption energy of CH4 on Co@HfS2 is stronger than those of Rh@HfS2 and Ir@HfS2, but the adsorption energy is still very small. By applying biaxial strain to Co@HfS2, we found that the adsorption energy increases with the increase in negative strain. This study provides a theoretical basis for the regulation of the adsorption properties of HfS2 by different transition metals.

7.
Physiol Plant ; 176(4): e14433, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38994561

RESUMO

Cadmium (Cd) is a leading environmental issue worldwide. The current study was conducted to investigate Cd tolerance of 10 commercial white clover (Trifolium repens) cultivars during seed germination and to further explore differences in lipid remodelling, glycometabolism, and the conversion of lipids into sugars contributing to Cd tolerance in the early phase of seedling establishment as well as the accumulation of Cd in seedlings and mature plants. The results show that Cd stress significantly reduced seed germination of 10 cultivars. Compared to Cd-sensitive Sulky, Cd-tolerant Pixie accelerated amylolysis to produce more glucose, fructose, and sucrose by maintaining higher amylase and sucrase activities under Cd stress. Pixie maintained higher contents of various lipids, higher DGDG/MGDG ratio, and lower unsaturation levels of lipids, which could be beneficial to membrane stability and integrity as well as signal transduction in cells after being subjected to Cd stress. In addition, Pixie upregulated expression levels of key genes (TrACX1, TrACX4, TrSDP6, and TrPCK1) involved in the conversion of lipids into sugars for early seedling establishment under Cd stress. These findings indicate that lipid remodelling, enhanced glycometabolism, and accelerated conversion of lipids into sugars are important adaptive strategies for white clover seed germination and subsequent seedling establishment under Cd stress. In addition, Pixie not only accumulated more Cd in seedlings and mature plants than Sulky but also had significantly better growth and phytoremediation efficiency under Cd stress. Pixie could be used as a suitable and critical germplasm for the rehabilitation and re-establishment of Cd-contaminated areas.


Assuntos
Cádmio , Germinação , Sementes , Trifolium , Cádmio/toxicidade , Germinação/efeitos dos fármacos , Trifolium/efeitos dos fármacos , Trifolium/metabolismo , Trifolium/genética , Trifolium/crescimento & desenvolvimento , Trifolium/fisiologia , Sementes/efeitos dos fármacos , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Açúcares/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
8.
Phys Chem Chem Phys ; 26(3): 2082-2092, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38131401

RESUMO

Nitrogen fixation using electrochemical methods on the surface of single-atom catalysts (SACs) provides a highly feasible strategy for green and low-energy-consumption ammonia (NH3) production. Herein, using density functional theory (DFT) calculations, we explored in detail the potential of monolayer BC3N2 SACs supported with 3d transition metal (TM) atoms (TM@BC3N2) to facilitate nitrogen reduction. The results revealed that the TM@BC3N2 systems exhibited remarkable catalytic activity in the nitrogen-reduction reaction (NRR). The fine NRR activity was related to the just-right bonding/antibonding orbital interactions between the 2π* of N2 and the d orbitals of the TM ions. The nitrogen-adsorption configurations were found to have different activation mechanisms. In addition, the effects of convectively formed convex nitrogen defects (VN) on the interaction between N2 and VN-TM@BC3N2 and the NRR process of VN-TM@BC3N2 were studied, and it was found that VN could fine-tune the reaction efficiency of the eNRR because after N atom dissociation to form VN, the interaction of TM-C3 was enhanced, and the activation of nitrogen and adsorption of NH3 by the TM-active centers were weakened. The present study can be used as a motivation for further experimental and theoretical research of 2D monolayers as NRR electrocatalysts.

9.
J Chem Phys ; 160(21)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38828804

RESUMO

Fullerene-chromophore dyads have attracted a great deal of research interest because these complexes can be potentially designed as nanoscale artificial photosynthetic centers, in which the chromophore and fullerene function as the electron donor and acceptor, respectively. The basic operation of this dyad-type artificial reaction center is photoinduced electron transfer from the donor to the acceptor. The fullerene and chromophore are usually covalently linked so that sufficient electronic coupling between these two moieties can facilitate the electron transfer. However, other deactivation pathways for the chromophore excited state, such as energy transfer to the fullerene, may reduce the quantum yield of the photoinduced electron transfer. Here, a series of C60-perylene dyads is exploited to interrogate the effect of the linkage on deactivation mechanisms of the chromophore excited state. For the C60-perylene dyads with a single or double bond bridge, we find that the decay of the singlet state of the chromophore is dominated by the electron transfer, and the corresponding time constant is determined to be 45 ps. On the other hand, for the dyad with a triple bond bridge, the singlet state of the chromophore is quickly quenched through energy transfer to fullerene, and the time constant is as short as 7.9 ps. Our finding suggests that the bond order of the bridge in the fullerene-chromophore dyads can be utilized to control the deactivation pathways of the excited state.

10.
Ergonomics ; : 1-19, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38781044

RESUMO

Technological breakthroughs such as artificial intelligence and sensors make human-robot collaboration a reality. Robots with highly reliable, specialised skills gain informal status in collaborative teams, but factors such as unstructured work environments and task requirements make robot error inevitable. So how do status differences of errant robots affect the desire for contact, and do team characteristics also have an impact? This paper describes an intergroup experiment using the Experimental Vignette Method (EVM), based on the Expectation Violation Theory, 214 subjects were invited to test the following hypotheses: (1) Errant robot status has an influence on employees' desire for contact and support for robotics research through negative emotions; (2) Team interdependence is a boundary condition for the effect of errant robot status on negative emotions. This paper contributes to the literature on employee reactions to robot errors in human-robot collaboration and provides suggestions for robot status design.


Complex human-robot collaboration inevitably leads to the phenomenon of robot errors. Based on this, we used an Experimental Vignette Method and found that differences in robot status design and human-robot team design features significantly affect employees' cognitive psychology after robot errors and reduce the negative consequences.

11.
Zhongguo Zhong Yao Za Zhi ; 49(8): 2117-2127, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38812227

RESUMO

Piperlongumine(PL), a natural alkaloid extracted from Piperis Longi Fructus, has attracted much attention in recent years because of its strong anti-tumor activity, little toxicity to normal cells, and excellent sensitizing effect combined with chemotherapy and radiotherapy, which endow PL with unique advantages as an anti-tumor drug. However, similar to other alkaloids, PL has low water solubility and poor bioavailability. To improve the application of PL in the clinical treatment of tumors, researchers have constructed various nano-drug delivery systems to increase the efficiency of PL delivery. This paper reviewed the physicochemical properties, anti-tumor mechanism, combined therapies, and nano-drug delivery systems of PL in recent years. The review aimed to provide a reference for further research on the anti-tumor effect and nano-drug delivery system of PL. Moreover, this review is expected to provide a reference for the development and application of PL in the anti-tumor therapies.


Assuntos
Dioxolanos , Neoplasias , Dioxolanos/química , Humanos , Animais , Neoplasias/tratamento farmacológico , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/administração & dosagem , Sistemas de Liberação de Fármacos por Nanopartículas/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Piperidonas
12.
J Cell Sci ; 134(24)2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34817059

RESUMO

The disruption of endosomal actin architecture negatively affects endocytic recycling. However, the underlying homeostatic mechanisms that regulate actin organization during recycling remain unclear. In this study, we identified a synergistic endosomal actin assembly restricting mechanism in C. elegans involving WTS-1, the homolog of LATS kinases, which is a core component of the Hippo pathway. WTS-1 resides on the sorting endosomes and colocalizes with the actin polymerization regulator PTRN-1 [the homolog of the calmodulin-regulated spectrin-associated proteins (CAMSAPs)]. We observed an increase in PTRN-1-labeled structures in WTS-1-deficient cells, indicating that WTS-1 can limit the endosomal localization of PTRN-1. Accordingly, the actin overaccumulation phenotype in WTS-1-depleted cells was mitigated by the associated PTRN-1 loss. We further demonstrated that recycling defects and actin overaccumulation in WTS-1-deficient cells were reduced by the overexpression of constitutively active UNC-60A(S3A) (a cofilin protein homolog), which aligns with the role of LATS as a positive regulator of cofilin activity. Altogether, our data confirmed previous findings, and we propose an additional model, that WTS-1 acts alongside the UNC-60A-mediated actin disassembly to restrict the assembly of endosomal F-actin by curbing PTRN-1 dwelling on endosomes, preserving recycling transport.


Assuntos
Actinas , Proteínas de Caenorhabditis elegans , Proteínas Serina-Treonina Quinases , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Endossomos , Proteínas dos Microfilamentos/genética
13.
Mol Genet Genomics ; 298(4): 823-836, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37059908

RESUMO

Coronavirus 2019 (COVID-19) is a complex disease that affects billions of people worldwide. Currently, effective etiological treatment of COVID-19 is still lacking; COVID-19 also causes damages to various organs that affects therapeutics and mortality of the patients. Surveillance of the treatment responses and organ injury assessment of COVID-19 patients are of high clinical value. In this study, we investigated the characteristic fragmentation patterns and explored the potential in tissue injury assessment of plasma cell-free DNA in COVID-19 patients. Through recruitment of 37 COVID-19 patients, 32 controls and analysis of 208 blood samples upon diagnosis and during treatment, we report gross abnormalities in cfDNA of COVID-19 patients, including elevated GC content, altered molecule size and end motif patterns. More importantly, such cfDNA fragmentation characteristics reflect patient-specific physiological changes during treatment. Further analysis on cfDNA tissue-of-origin tracing reveals frequent tissue injuries in COVID-19 patients, which is supported by clinical diagnoses. Hence, our work demonstrates and extends the translational merit of cfDNA fragmentation pattern as valuable analyte for effective treatment monitoring, as well as tissue injury assessment in COVID-19.


Assuntos
COVID-19 , Ácidos Nucleicos Livres , Humanos , COVID-19/diagnóstico , Ácidos Nucleicos Livres/genética
14.
Small ; 19(12): e2206662, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36587975

RESUMO

The development of high-performance lead-free dielectric ceramic capacitors is essential in the field of advanced electronics and electrical power systems. A huge challenge, however, is how to simultaneously realize large recoverable energy density (Wrec ), ultrahigh efficiency (η), and satisfactory temperature stability to effectuate next-generation high/pulsed power capacitors applications. Here, a strategy of utilizing nanoscale polarization heterogeneous regions is demonstrated for high-performance dielectric capacitors, showing comprehensive properties of large Wrec (≈6.39 J cm-3 ) and ultrahigh η (≈94.4%) at 700 kV cm-1 accompanied by excellent thermal endurance (20-160 °C), frequency stability (5-200 Hz), cycling reliability (1-105 cycles) at 500 kV cm-1 , and superior charging-discharging performance (discharge rate t0.9 ≈ 28.4 ns, power density PD ≈161.3 MW cm-3 ). The observations reveal that constructing the polarization heterogeneous regions in a linear dielectric to form novel relaxor ferroelectrics produces favorable microstructural characters, including extremely small polar nanoregions with high dynamics and multiphase coexistence and stable local structure symmetry, which enables large breakdown strength and ultralow polarization switching hysteresis, hence synergistically contributing to high-efficient capacitive energy storage. This study thus opens up a novel strategy to design lead-free dielectrics with comprehensive high-efficient energy storage performance for advanced pulsed power capacitors applications.

15.
Langmuir ; 39(7): 2618-2630, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36775933

RESUMO

The application of intrinsic and transition metals (TM)-doped VSe2 monolayers for the detection of faulty gases in SF6 electrical insulated equipment is investigated based on first-principles calculations. The electron density difference, density of state, and adsorption energy are analyzed to further clarify the reaction mechanism. The results show that the intrinsic VSe2 monolayer has weak adsorption performance for SO2 and SOF2 molecules, but the adsorption properties of the system are significantly improved after doping TM atoms. Among them, the TM-doped VSe2 monolayer has better sensing performance for SO2 than for SOF2 molecules. Furthermore, the modulating effect of biaxial strain on the gas-sensitive properties of TM-doped VSe2 system is also analyzed. Finally, the recovery time of the gas molecules on the solid adsorbent is evaluated. The results confirm that the TM-doped VSe2 monolayer can be used as a novel sensing material or scavenger to ensure the normal operation of SF6 electrical insulated equipment. This will provide a prospective insight for experimenters to implement VSe2-based sensing materials or scavengers.

16.
Langmuir ; 39(25): 8879-8888, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37310231

RESUMO

The adsorption of five small gas molecules (CO, CO2, NO, NO2, and NH3) on transition metal (TM)-modified ZrSe2 monolayers (Au-ZrSe2 and Pt-ZrSe2) are studied based on first principles. The adsorption structure, adsorption energy (Eads), electron transfer (Qt), and density of states (DOS) with intrinsic ZrSe2, Au-ZrSe2, and Pt-ZrSe2 monolayers are discussed, and their sensing performance is evaluated. The results show that the electrical conductivity of ZrSe2 is obviously increased after Au and Pt atom modification. The intrinsic ZrSe2 adsorbs the five kinds of gas molecules weakly, while ZrSe2 modified by the Au or Pt atom improves the adsorption of the gas molecules in different degrees. Au-ZrSe2 has the best adsorption effect on NO2 gas molecules, while Pt-ZrSe2 shows strong sensitivity to CO gas molecules. Moreover, Au-ZrSe2 and Pt-ZrSe2 are of great significance for the adsorption sensing mechanism and also offer prospective materials for the advancement of gas-sensitive sensors.

17.
Langmuir ; 39(36): 12662-12670, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37652891

RESUMO

This paper reports the adsorption of toxic gases (NO2, SO2, and NH3) on a MoSeTe structure based on first principles. It was found that the gas (NO2, SO2, and NH3) adsorption on a pure MoSeTe monolayer was weak; however, the adsorption performance of these gas molecules on transition-metal-atom-supported MoSeTe monolayers (TM-MoSeTe) was better than that on pure MoSeTe monolayers. In addition, there was more charge transfer between gas molecules and TM-MoSeTe. By comparing the adsorption energy and charge transfer values, the trend of adsorption energy and charge transfer in the adsorption of NO2 and SO2 was determined to be Fe-MoSeTe > Co-MoSeTe > Ni-MoSeTe. For the adsorption of NH3, the effect trend was as follows: Co-MoSeTe > Ni-MoSeTe > Fe-MoSeTe. Finally, by comparing their response times, the better gas sensor was selected. The Ni-MoSeTe system is suitable for NO2 gas sensors, and the Fe-MoSeTe and Co-MoSeTe systems are suitable for SO2 gas sensors. The Fe-MoSeTe, Co-MoSeTe, and Ni-MoSeTe systems are all suitable for NH3 gas sensors. Janus transition-metal dichalcogenides have the potential to be used as gas-sensing and scavenging materials.

18.
Langmuir ; 39(42): 15142-15151, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37812576

RESUMO

In this study, DFT calculations are used to analyze the adsorption of industrial waste gases (NO2, SO2, H2S, and NH3) on WSe2 monolayers. The adsorption energy, energy band, density of states, charge transfer, and recovery time of the adsorption structures between the target gas molecules and the Os-doped WSe2 are studied. Compared with pure WSe2 monolayer, Os surface bonding doping WSe2 (Os-modified WSe2) and Os doping with Se vacancy of WSe2 (Os-embedded WSe2) exhibit improved gas molecule adsorption ability. Among them, the adsorption energy of the Os-modified WSe2 monolayer on NO2, SO2, H2S, and NH3 is greater than that of the WSe2 monolayer. At the same time, it is proved that the Os-embedded WSe2 can be used as a gas sensor for H2S and NH3 gas molecules at a high temperature.

19.
Langmuir ; 39(31): 10769-10778, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37491738

RESUMO

Building two-dimensional (2D) vertical van der Waals heterostructures (vdWHs) is one of the effective methods to regulate the properties of single 2D materials. In this paper, we stack the hexagonal boron nitride (h-BN) monolayer (ML) on the SnSe2 ML to construct the stable h-BN/SnSe2 vdWH, of which the crystal and electronic structures, together with the optical properties, are also analyzed by the first-principles calculations. The results show that the h-BN/SnSe2 vdWH belongs to a type-I heterostructure with an indirect bandgap of 1.33 eV, in which the valence band maximum and conduction band minimum are both determined by the component SnSe2 ML. Interestingly, the h-BN/SnSe2 vdWH under the tensile strain or electric field undergoes the transitions both from type-I to type-II heterostructure and from the indirect to direct bandgap semiconductor. In addition, the carrier mobility of the h-BN/SnSe2 heterostructure has a significant enhancement relative to that of the SnSe2 ML, up to 104 cm2 V-1 s-1. Meanwhile, the h-BN/SnSe2 heterostructure presents the superb optical absorption and unique type-II hyperbolic property. Our findings will broaden the potential applications of SnSe2 ML and provide theoretical guidance for the related experimental studies.

20.
Phys Chem Chem Phys ; 25(36): 24721-24732, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37670691

RESUMO

The rational design and development of an efficient bifunctional catalyst for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is the key to developing new renewable energy storage and conversion technologies. Transition metal nitrides (TMNs) have shown excellent energy storage and electrochemistry potential due to their unique electronic structure and physicochemical properties. In this paper, based on the first-principles method of density functional theory (DFT), a series of efficient and stable bifunctional single-atom catalysts (SACs) were designed on Mo2N by introducing transition metal atoms as active sites, and the effects of different TM atoms on the catalytic performance of 2D-Mo2N (Two dimensional Mo2N) were evaluated. The calculation results show that TM@Mo2N exhibits excellent stability and good conductivity, which is conducive to electron transfer during the electrocatalytic reaction. Among these SACs, the Au@Mo2N single-atom catalyst has a very low OER overpotential (0.36 V), exhibiting high OER activity. Meanwhile, Au@Mo2N also exhibits excellent ORR performance with a low overpotential of 0.4 V, indicating that Au@Mo2N is the best OER/ORR bifunctional catalyst. This work provides a feasible solution for developing transition metal bifunctional electrocatalysts. Au@Mo2N is expected to replace traditional commercial Pt catalyst materials and become a catalyst with excellent performance in fuel cell modules.

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