Publications by authors named "Tuan V Vu"

15 Publications

  • Page 1 of 1

Interfacial Electronic Properties and Tunable Contact Types in Graphene/Janus MoGeSiN Heterostructures.

J Phys Chem Lett 2021 Apr 19;12(16):3934-3940. Epub 2021 Apr 19.

Department of Materials Science and Engineering, Le Quy Don Technical University, Hanoi 100000, Vietnam.

Two-dimensional MoSiN is an emerging class of 2D MAN family, which has recently been synthesized in experiment. Herein, we construct ultrathin van der Waals heterostructures between graphene and a new 2D Janus MoGeSiN material and investigate their interfacial electronic properties and tunable Schottky barriers and contact types using first-principles calculations. The GR/MoGeSiN vdWHs are expected to be energetically favorable and stable. The high carrier mobility in graphene/MoGeSiN vdWHs makes them suitable for high-speed nanoelectronic devices. Furthermore, depending on the stacking patterns, either an n-type or a p-type Schottky contact is formed at the GR/MoGeSiN interface. The strain engineering and electric field can lead to the transformation from an n-type to a p-type Schottky contact or from Schottky to Ohmic contact in graphene/MoGeSiN heterostructure. These findings provide useful guidance for designing controllable Schottky nanodevices based on graphene/MoGeSiN heterostructures with high-performance.
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http://dx.doi.org/10.1021/acs.jpclett.1c00682DOI Listing
April 2021

Electronic, optical, and thermoelectric properties of Janus In-based monochalcogenides.

J Phys Condens Matter 2021 May 4;33(22). Epub 2021 May 4.

Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam.

Inspired by the successfully experimental synthesis of Janus structures recently, we systematically study the electronic, optical, and electronic transport properties of Janus monolayers In(/= S, Se, Te with≠) in the presence of a biaxial strain and electric field using density functional theory. Monolayers Inare dynamically and thermally stable at room temperature. At equilibrium, both InSTe and InSeTe are direct semiconductors while InSSe exhibits an indirect semiconducting behavior. The strain significantly alters the electronic structure of Inand their photocatalytic activity. Besides, the indirect-direct gap transitions can be found due to applied strain. The effect of the electric field on optical properties of Inis negligible. Meanwhile, the optical absorbance intensity of the Janus Inmonolayers is remarkably increased by compressive strain. Also, Inmonolayers exhibit very low lattice thermal conductivities resulting in a high figure of merit, which makes them potential candidates for room-temperature thermoelectric materials.
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http://dx.doi.org/10.1088/1361-648X/abf381DOI Listing
May 2021

An evaluation of source apportionment of fine OC and PM by multiple methods: APHH-Beijing campaigns as a case study.

Faraday Discuss 2021 Mar 26;226:290-313. Epub 2020 Nov 26.

School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, B15 2TT, UK.

This study aims to critically evaluate the source apportionment of fine particles by multiple receptor modelling approaches, including carbon mass balance modelling of filter-based radiocarbon (C) data, Chemical Mass Balance (CMB) and Positive Matrix Factorization (PMF) analysis on filter-based chemical speciation data, and PMF analysis on Aerosol Mass Spectrometer (AMS-PMF) or Aerosol Chemical Speciation Monitor (ACSM-PMF) data. These data were collected as part of the APHH-Beijing (Atmospheric Pollution and Human Health in a Chinese Megacity) field observation campaigns from 10 November to 12 December in winter 2016 and from 22 May to 24 June in summer 2017. C analysis revealed the predominant contribution of fossil fuel combustion to carbonaceous aerosols in winter compared with non-fossil fuel sources, which is supported by the results from other methods. An extended Gelencsér (EG) method incorporating C data, as well as the CMB and AMS/ACSM-PMF methods, generated a consistent source apportionment for fossil fuel related primary organic carbon. Coal combustion, traffic and biomass burning POC were comparable for CMB and AMS/ACSM-PMF. There are uncertainties in the EG method when estimating biomass burning and cooking OC. The POC from cooking estimated by different methods was poorly correlated, suggesting a large uncertainty when differentiating this source type. The PM source apportionment results varied between different methods. Through a comparison and correlation analysis of CMB, PMF and AMS/ACSM-PMF, the CMB method appears to give the most complete and representative source apportionment of Beijing aerosols. Based upon the CMB results, fine aerosols in Beijing were mainly secondary inorganic ion formation, secondary organic aerosol formation, primary coal combustion and from biomass burning emissions.
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http://dx.doi.org/10.1039/d0fd00095gDOI Listing
March 2021

Proposal of new spinel oxides semiconductors ZnGaO, [ZnGaO]:Mn and Rh: ab-initio calculations and prospects for thermophysical and optoelectronic applications.

J Mol Graph Model 2020 12 10;101:107750. Epub 2020 Sep 10.

Department of Basic Sciences, Military College of Engineering, National University of Science and Technology (NUST), Islamabad, Pakistan.

Transparent conducting oxides (TCOs) of semiconductor family gained significant attention due to increasing trends in the optoelectronic and thermo-physical applications. In current work, we reported electronic, optical, transport and thermodynamical properties of spinel oxides ZnGaO, [ZnGaO]:Mn and [ZnGaO]:Rh compounds. Based on DFT, we employed first-principles calculations implemented in Wien 2k using the modified-Becke-Johnson (mBJ) on parent spinel and generalized-gradient-approximation plus Hubbard potential U (GGA + U) on doped materials, respectively. The calculated band structure shows insulating nature of parent compound, while doped material observed semiconducting nature contains direct band gap for both spin channels with band gaps of [ZnGaO]:Mn (0.59 up, 2.4 eV dn) and [ZnGaO]:Rh (2.1 eV up/dn) respectively. The electronic and optical results reveal that hybridization occurred mainly due to O-p/Zn, Mn-d, Rh-d and Ga-s orbitals. It is analyzed that Mn-doped material shows good absorption in the visible region while other are good in UV region. The effective masses of spinel oxides are also computed at high symmetry directions hence varied nonlinearly with the doping. The stability of materials is checked by calculating formation energies which indicate Mn-doped spinel oxide is most stable as that of others. The thermoelectric properties of spinel oxides were carried out by Post-DFT (Boltztrap) calculations. Large values of Seebeck coefficient and power factor of Mn-doped spinel oxide indicate that this material can be used for thermoelectric devices. The thermodynamical properties are calculated by quasi-harmonic Debye model implemented in GIBBS 2 code. Moreover, the pressure and temperature dependence of all (TD) parameters of investigated spinel oxides are analyzed using quasi-harmonic Debye model.
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http://dx.doi.org/10.1016/j.jmgm.2020.107750DOI Listing
December 2020

Source apportionment of fine organic carbon (OC) using receptor modelling at a rural site of Beijing: Insight into seasonal and diurnal variation of source contributions.

Environ Pollut 2020 Nov 26;266(Pt 1):115078. Epub 2020 Jun 26.

Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom. Electronic address:

This study was designed to investigate the seasonal characteristics and apportion the sources of organic carbon during non-haze days (<75 μg m) and haze (≥75 μg m) events at Pinggu, a rural Beijing site. Time-resolved concentrations of carbonaceous aerosols and organic molecular tracers were measured during the winter of 2016 and summer 2017, and a Chemical Mass Balance (CMB) model was applied to estimate the average source contributions. The concentration of OC in winter is comparable with previous studies, but relatively low during the summer. The CMB model apportioned seven separate primary sources, which explained on average 73.8% on haze days and 81.2% on non-haze days of the organic carbon in winter, including vegetative detritus, biomass burning, gasoline vehicles, diesel vehicles, industrial coal combustion, residential coal combustion and cooking. A slightly lower percentage of OC was apportioned in the summer campaign with 64.5% and 78.7% accounted for. The other unapportioned OC is considered to consist of secondary organic carbon (SOC). During haze episodes in winter, coal combustion and SOC were the dominant sources of organic carbon with 23.3% and 26.2%, respectively, followed by biomass burning emissions (20%), whereas in summer, industrial coal combustion and SOC were important contributors. Diurnal contribution cycles for coal combustion and biomass burning OC showed a peak at 6-9 pm, suggesting domestic heating and cooking were the main sources of organic aerosols in this rural area. Backward trajectory analysis showed that high OC concentrations were measured when the air mass was from the south, suggesting that the organic aerosols in Pinggu were affected by both local emissions and regional transport from central Beijing and Hebei province during haze episodes. The source apportionment by CMB is compared with the results of a Positive Matrix Factorization (PMF) analysis of ACSM data for non-refractory PM, showing generally good agreement.
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http://dx.doi.org/10.1016/j.envpol.2020.115078DOI Listing
November 2020

First-principles investigation of nonmetal doped single-layer BiOBr as a potential photocatalyst with a low recombination rate.

Phys Chem Chem Phys 2020 Jul 26;22(27):15354-15364. Epub 2020 Jun 26.

Department of Ceramics, College of Materials Engineering, University of Babylon, 51002, Hilla, Iraq.

Nonmetal doping is an effective approach to modify the electronic band structure and enhance the photocatalytic performance of bismuth oxyhalides. Using density functional theory, we systematically examine the fundamental properties of single-layer BiOBr doped with boron (B) and phosphorus (P) atoms. The stability of the doped models is investigated based on the formation energies, where the substitutional doping is found to be energetically more stable under O-rich conditions than under Bi-rich ones. The results showed that substitutional doping of P atoms reduced the bandgap of pristine BiOBr to a greater extent than that of boron substitution. The calculation of the effective masses reveals that B doping can render the electrons and holes of pristine BiOBr lighter and heavier, respectively, resulting in a slower recombination rate of photoexcited electron-hole pairs. Based on the results of HOMO-LUMO calculations, the introduction of B atoms tends to increase the number of photocatalytically active sites. The top of the valence band and the conduction band bottom of the B doped BiOBr monolayer match well with the water redox potentials in an acidic environment. The absorption spectra propose that B(P) doping causes a red-shift. Overall, the results predict that nonmetal-doped BiOBr monolayers have a reduced bandgap, a slow recombination rate, more catalytically active sites, enhanced optical absorption edges, and reduced work functions, which will contribute to superior photocatalytic performance.
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http://dx.doi.org/10.1039/d0cp02007aDOI Listing
July 2020

Effects of different surface functionalization on the electronic properties and contact types of graphene/functionalized-GeC van der Waals heterostructures.

Phys Chem Chem Phys 2020 Apr;22(15):7952-7961

Department of Materials Science and Engineering, Le Quy Don Technical University, Ha Noi 100000, Vietnam.

Constructing vertical heterostructures by placing graphene (Gr) on two-dimensional materials has recently emerged as an effective way to enhance the performance of nanoelectronic and optoelectronic devices. In this work, first principles calculations are employed to explore the structural and electronic properties of Gr/GeC and Gr/functionalized-GeC by H/F/Cl surface functionalization. Our results imply that the electronic properties of the Gr, GeC and all functionalized-GeC monolayers are well preserved in Gr/GeC and Gr/functionalized-GeC heterostructures, and the Gr/GeC heterostructure forms a p-type Schottky contact. Interestingly, we find that the p-type Schottky contact in Gr/GeC can be converted into the n-type one and into an n-type ohmic contact by H/F/Cl surface functionalization to form Gr/functionalized-GeC heterostructures. Furthermore, we find that electric fields and strain engineering can change both the Schottky barrier heights and the contact types of the Gr/functionalized-GeC vdWHs. These findings suggest that Gr/functionalized-GeC heterostructures can be considered as a promising candidate for designing high-performance optoelectronic and nanoelectronic devices.
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http://dx.doi.org/10.1039/c9cp07009eDOI Listing
April 2020

On the in-plane electronic thermal conductivity of biased nanosheet β-borophene.

Phys Chem Chem Phys 2020 Mar 5;22(11):6318-6325. Epub 2020 Mar 5.

Division of Computational Physics, Institute for Computational Science, Ton Duc Thang University, Ho Chi Minh City, Vietnam.

The unique physical and chemical properties of β-borophene stem from the coexistence of the Dirac and triplet fermions. The metallic phase of β-borophene transitions to the semiconducting one when it is subjected to a perpendicular electric field or bias voltage. In this work, with the aid of a five-band tight-binding Hamiltonian, the Green's function approach and the Kubo-Greenwood formalism, the electronic thermal conductivity (ETC) of the semiconducting phase of β-borophene is studied. Two homogeneous (H) and inversion symmetric (IS) models are considered depending on the interaction of the substrate and boron atoms. In addition, due to the anisotropic structure of β-borophene, the swapping effect of bias poles is addressed. First of all, we find the pristine ETC < ETC independent of the temperature. Furthermore, a decrease of 74.45% (80.62%) is observed for ETC (ETC) when strong positive bias voltages are applied, while this is 25.2% (47.48%) when applying strong negative bias voltages. Moreover, the shoulder temperature of both models increases (fluctuates) with the positive (negative) bias voltage. Our numerical results pave the way for setting up future experimental thermoelectric devices in order to achieve the highest performance.
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http://dx.doi.org/10.1039/c9cp06606cDOI Listing
March 2020

Band alignment and optical features in Janus-MoSeTe/X(OH) (X = Ca, Mg) van der Waals heterostructures.

Phys Chem Chem Phys 2019 Nov;21(46):25849-25858

Division of Computational Physics, Institute for Computational Science, Ton Duc Thang University, Ho Chi Minh City, Vietnam.

van der Waals heterostructures can be effectively used to enhance the electronic and optical properties and extend the application range of two-dimensional materials. Here, we construct for the first time MoSeTe/X(OH)2 (X = Ca, Mg) heterostructures and investigate their electronic and optical properties as well as the relative orientation of these layers with respect to each other and the effects of an electric field. Our results show that in the MoSeTe/X(OH)2 heterostructures, the Janus MoSeTe monolayer is bonded to the X(OH)2 layer via weak van der Waals forces. Owing to different kinds of chalcogen Se and Te atoms in both sides of Janus MoSeTe, there exist two main stacking types of the MoSeTe/X(OH)2 heterostructures, that are MoSeTe-Se/X(OH)2 and MoSeTe-Te/X(OH)2 heterostructures. Interestingly, the Se- and Te-interface can induce straddling type-II and type-I band alignments. The MoSeTe-Se/X(OH)2 heterostructure exhibits a type-II band alignment, thus endowing it with a potential ability to separate photogenerated electrons and holes. Whereas, the MoSeTe-Te/Ca(OH)2 heterostructure displays a type-I band alignment, which may result in an ultrafast recombination between electrons and holes, making the MoSeTe-Te/Ca(OH)2 heterostructure a suitable material for optoelectronic applications. The MoSeTe/X(OH)2 heterostructures show an isotropic behavior in the low energy region while an anisotropic behaviour in the high photon energy region. The dielectric function of the MoSeTe-Te/Ca(OH)2 heterostructure is high at low photon energy relative to other heterostructures verifying it to have a good optical absorption. Furthermore, the band gap values and band alignment of the MoSeTe/X(OH)2 heterostructures can be modulated by applying an electric field, which induces semiconductor-to-metal and type-I(II) to type-II(I) band alignment. These results demonstrate that the MoSeTe/X(OH)2 heterostructures are promising candidates for optoelectronic and photovoltaic nanodevices.
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http://dx.doi.org/10.1039/c9cp06019gDOI Listing
November 2019

Tailoring the structural and electronic properties of an SnSe/MoS van der Waals heterostructure with an electric field and the insertion of a graphene sheet.

Phys Chem Chem Phys 2019 Oct;21(39):22140-22148

Division of Computational Physics, Institute for Computational Science, Ton Duc Thang University, Ho Chi Minh City, Vietnam.

van der Waals heterostructures (vdWHs), obtained by vertically stacking different two-dimensional (2D) layered materials are being considered intensively as potential materials for nanoelectronic and optoelectronic devices because they can show the most potential advantages of individual 2D materials. Here, we construct the SnSe2/MoS2 vdWH and investigate its electronic and optical properties using first-principles calculations. We find that the band structures of both MoS2 and SnSe2 monolayers are well kept in the SnSe2/MoS2 vdWH because of their weakly interacting features via vdW interaction. The SnSe2/MoS2 vdWH forms a type-I band alignment and exhibits an indirect semiconductor band gap of 0.45 eV. The type-I band alignment makes the SnSe2/MoS2 vdWH a promising material for optoelectronic nanodevices, such as light emitting diodes because of ultra-fast recombination of electrons and holes. Moreover, the band gap and band alignment of the SnSe2/MoS2 vdWH can be tailored by the electric field and the insertion of a graphene sheet. After applying an electric field, type-I to type-II and semiconductor to metal transitions can be achieved in the SnSe2/MoS2 vdWH. Besides, when a graphene sheet is inserted into the SnSe2/MoS2 vdWH to form three stacking types of G/SnSe2/MoS2, SnSe2/G/MoS2 and SnSe2/MoS2/G, the p-type semiconductor of the SnSe2/MoS2 vdWH is converted to an n-type Ohmic contact. These findings provide theoretical guidance for designing future nanoelectronic and optoelectronic devices based on the SnSe2/MoS2 vdWH.
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http://dx.doi.org/10.1039/c9cp04689eDOI Listing
October 2019

Synergistic effects of surfactants and heterogeneous nanoparticles at oil-water interface: Insights from computations.

J Colloid Interface Sci 2019 Oct 31;553:50-58. Epub 2019 May 31.

School of Chemical, Biological, and Material Engineering, University of Oklahoma, Norman, OK 73019-1004, USA. Electronic address:

Hypothesis: Nanoparticles (NPs) can reduce the interfacial tension (IFT) of the oil-water system containing surfactants by reducing the interfacial area available to surfactants. The ability to reduce the IFT when surfactants are present in addition to NPs depends on the localization of the NPs on the interface, which is related to the nature of the NPs and the interaction between NPs and surfactant molecules.

Experiments: Systems of NPs and surfactants on the oil-water interface were studied using dissipative particle dynamics (DPD). Heterogeneous NPs with different properties and interface coverage were placed on the interface with various surfactant concentrations. The IFT and the surfactant density profiles across the interface were analyzed.

Findings: At constant surfactant concentration, adding NPs reduced the IFT; while with the absence of surfactant, NPs expressed no effect on the IFT. Among different types of heterogeneous NPs, the most effective were those that maximized their footprint on the interface, reducing thus the interfacial area available to surfactants. The interactions of the NPs with the surfactant molecules determined exactly which pattern of heterogeneity was most favorable. Based on these results, suggestions for designing NPs for maximum synergistic effects with surfactants were formulated.
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http://dx.doi.org/10.1016/j.jcis.2019.05.102DOI Listing
October 2019

Oil-water interfaces with surfactants: A systematic approach to determine coarse-grained model parameters.

J Chem Phys 2018 May;148(20):204704

School of Chemical, Biological, and Material Engineering, University of Oklahoma, Norman, Oklahoma 73019-1004, USA.

In order to investigate the interfacial region between oil and water with the presence of surfactants using coarse-grained computations, both the interaction between different components of the system and the number of surfactant molecules present at the interface play an important role. However, in many prior studies, the amount of surfactants used was chosen rather arbitrarily. In this work, a systematic approach to develop coarse-grained models for anionic surfactants (such as sodium dodecyl sulfate) and nonionic surfactants (such as octaethylene glycol monododecyl ether) in oil-water interfaces is presented. The key is to place the theoretically calculated number of surfactant molecules on the interface at the critical micelle concentration. Based on this approach, the molecular description of surfactants and the effects of various interaction parameters on the interfacial tension are investigated. The results indicate that the interfacial tension is affected mostly by the head-water and tail-oil interaction. Even though the procedure presented herein is used with dissipative particle dynamics models, it can be applied for other coarse-grained methods to obtain the appropriate set of parameters (or force fields) to describe the surfactant behavior on the oil-water interface.
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http://dx.doi.org/10.1063/1.5022798DOI Listing
May 2018

Physical properties and lung deposition of particles emitted from five major indoor sources.

Air Qual Atmos Health 2017 25;10(1):1-14. Epub 2016 Aug 25.

Division of Environmental Health & Risk Management, School of Geography, Earth & Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT UK ; Department of Environmental Sciences/Center of Excellence in Environmental Studies, King Abdulaziz University, PO Box 80203, Jeddah, 21589 Saudi Arabia.

The physical properties of indoor particles were measured with an Scanning Mobility Particle Sizer (SMPS) system (14.6-850 nm), an Aerodynamic Particle Sizer (APS, 0.54-18 μm) and an Hygroscopic Tandem Differential Mobility Analyzer (H-TDMA) in an apartment located in an urban background site in Prague (Czech Republic) from 15 August to 8 September, 2014. The total particle maximum number concentration was 9.38 × 10, 1.46 × 10, 2.89 × 10, 2.25 × 10 and 1.57 × 10 particles cm for particles released from vacuum cleaning, soap/W5 cleaning spray, smoking, incense burning and cooking (frying) activities, respectively. Particles emitted from cleaning activities showed unimodal number size distributions, with the majority of particles (>98.2 %) in the ultrafine size range (Dp <100 nm) and modes at a diameter of 19.8 nm for vacuum cleaning and 30.6 nm for soap/W5 cleaning. Smoking and incense burning predominantly generated particles in the accumulation mode with a count median diameter around 90-150 nm while cooking emissions showed a bimodal structure with a main mode at 47.8 nm. Particles from vacuum cleaning, incense burning, smoking and cooking emissions were found to be "nearly hydrophobic" with an average growth factor (G) around 1.01-1.10, while particles emitted from desk cleaning using organic compounds were found to be "less-hygroscopic" (G ∼1.12-1.16). Based on an adjusted MPPD model with a consideration of the hygroscopic properties of particles, the total lung deposition fractions of these particles by number when they penetrate into the human lung were 0.73 ± 0.02, 0.62 ± 0.03, 0.37 ± 0.03, 0.32 ± 0.03 and 0.49 ± 0.02 for vacuum cleaning, desk cleaning, smoking, incense burning and cooking, respectively.
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http://dx.doi.org/10.1007/s11869-016-0424-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5216066PMC
August 2016

Manifestation of Anomalous Weak Space-Charge-Density Acentricity for a TlHgBr Single Crystal.

Inorg Chem 2016 Oct 3;55(20):10547-10557. Epub 2016 Oct 3.

Institute of Physics, J. Dlugosz University of Częstochowa , Armii Krajowej 13/15, PL-42-200 Częstochowa, Poland.

Density functional theory (DFT) calculations within the concept of the MBJ+U+SO (modified Becke-Johnson potential + U + spin orbit) approach were performed for a TlHgBr single crystal for the first time assuming weak noncentrosymmetry (space group P4nc). Excellent agreement was achieved between the calculated and experimental band-gap-energy magnitudes as well as the density of electronic states measured by the X-ray photoelectron spectroscopy method. It is a very principal result because usually the DFT calculations underestimate the energy-gap values. In the present study, we carry out calculations of the optical properties (absorption coefficient, real and imaginary parts of the dielectric function, electron energy-loss spectrum, refractive index, extinction coefficient, and optical reflectivity dispersions). It has been established that the principal origin of the observed weak acentricity is determined by delocalized band states at the top of the valence band originating from the p states of the Br atoms.
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http://dx.doi.org/10.1021/acs.inorgchem.6b01389DOI Listing
October 2016

Source apportionment of wide range particle size spectra and black carbon collected at the airport of Venice (Italy).

Atmos Environ (1994) 2016 Aug 10;139:56-74. Epub 2016 May 10.

Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom.

Atmospheric particles are of high concern due to their toxic properties and effects on climate, and large airports are known as significant sources of particles. This study investigates the contribution of the Airport of Venice (Italy) to black carbon (BC), total particle number concentrations (PNC) and particle number size distributions (PNSD) over a large range (14 nm-20 μm). Continuous measurements were conducted between April and June 2014 at a site located 110 m from the main taxiway and 300 m from the runway. Results revealed no significantly elevated levels of BC and PNC, but exhibited characteristic diurnal profiles. PNSD were then analysed using both -means cluster analysis and positive matrix factorization. Five clusters were extracted and identified as midday nucleation events, road traffic, aircraft, airport and nighttime pollution. Six factors were apportioned and identified as probable sources according to the size profiles, directional association, diurnal variation, road and airport traffic volumes and their relationships to micrometeorology and common air pollutants. Photochemical nucleation accounted for ∼44% of total number, followed by road + shipping traffic (26%). Airport-related emissions accounted for ∼20% of total PNC and showed a main mode at 80 nm and a second mode beyond the lower limit of the SMPS (<14 nm). The remaining factors accounted for less than 10% of number counts, but were relevant for total volume concentrations: nighttime nitrate, regional pollution and local resuspension. An analysis of BC levels over different wind sectors revealed no especially significant contributions from specific directions associated with the main local sources, but a potentially significant role of diurnal dynamics of the mixing layer on BC levels. The approaches adopted in this study have identified and apportioned the main sources of particles and BC at an international airport located in area affected by a complex emission scenario. The results may underpin measures for improving local and regional air quality, and health impact assessment studies.
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http://dx.doi.org/10.1016/j.atmosenv.2016.05.018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7108445PMC
August 2016