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Four main anode types are generally considered as typical anodes for Li-ion batteries (LIBs): Li-metal, carbon-based, alloy-based, and oxide-based anodes. Although they exhibit satisfactory electrochemical performance as LIB anodes, they cannot simultaneously satisfy all key requirements for LIB anodes: high reversible capacity, high initial Coulombic efficiency (ICE), long cycle life, fast rate capability, structural stability, and no safety concerns. Here, we suggest Li-compound anodes as a promising class of high-performance LIB anodes. Three binary (LiSn, Li

This study reports measurements of size-resolved aerosol composition at a site in Incheon along with other aerosol characteristics for contrast between Incheon (coastal) and Seoul (inland), South Korea, during a transboundary pollution event during the early part of an intensive sampling period between 4 and 11 March 2019. Anthropogenic emissions were dominant in the boundary layer over the study region between 4 and 6 March, with much smaller contributions from dust, smoke, and sea salt. The meteorology of this period (shallow boundary layer, enhanced humidity, and low temperature) promoted local heterogeneous formation of secondary inorganic and organic species, including high nitrate (NO3-) relative to sulfate (SO42-). Seoul exhibited higher PM2.5 levels than Incheon, likely due to local emissions. The following findings point to secondary aerosol formation and growth sensitivity to water vapor during this pollution event: (i) significant concentrations of individual inorganic and organic acids in the supermicrometer range relative to their full size range (∼40 %) at higher humidity; (ii) high correlation (r=0.95) between oxalate and SO42-, a marker of secondary aqueous production of oxalate; (iii) increased sulfur and nitrogen oxidation ratios as a function of humidity; and (iv) matching composition apportionment (for soluble ions) between the PM1 and PM2.5−1 size fractions. The last finding confirms that PM1 aerosol composition measurements fully capture PM2.5 composition apportionment (for soluble ions) during haze events and may therefore be reliably applied in modeling studies of such events over the full PM2.5 size range. However, the differences evident in the periods following the haze event imply that under other atmospheric conditions PM1 composition measurements will not fully reflect the apportionment of PM2.5 aerosols. The study period was marked by relatively low temperatures that made NO3- the most abundant species detected, pointing to the sensitivity of PM2.5 levels and composition as a function of season during such transboundary events. For instance, other such events in previous studies exhibited more comparable levels between SO42- and NO3- coincident with higher temperatures than the current study. This dataset can contribute to future evaluation of model PM2.5 composition to better support regulatory efforts to control PM2.5 precursors.

Electrocatalysts with dramatically enhanced water splitting efficiency, derived from controlled structures, phase transitions, functional activation

The aim of this study was to determine the effects of traffic-related particulate matter (PM) on allergic inflammation of ocular surfaces. BALB/c mice were sensitized with ovalbumin (OVA) and aluminum hydroxide via intraperitoneal injection. Two weeks later, mice were challenged with eye drops containing OVA concomitant with either traffic-related PM2.5 or vehicle eye drops. Topical OVA challenges were administered following unilateral subconjunctival injection of magnetic-bead-sorted CD11c+ dendritic cells (DC). The following were assessed: (1) clinical signs, (2) infiltration of inflammatory cells into conjunctiva, (3) serum levels of OVA-specific IgE production, and (4) T-cell cytokine secretion with topical application of PM2.5, compared to saline vehicle. PM2.5 was found to increase production of OVA-specific IgE in serum and Th2 immune response-related cytokines including interleukin (IL)-4, IL-17A, and IL-13 compared to vehicle control. It is of interest that PM2.5 treatment also elevated the population of mature DCs in draining lymph nodes (LNs). Exposure with PM2.5 was associated with a significant rise in conjunctival expression of IL-1β, IL-6, IL-17, and TNF. After subconjunctival injection of CD11c+DCs from PM2.5-treated allergic conjunctivitis (AC) mice into naive mice, T cell responses and OVA-specific IgE were also enhanced. Data suggest that traffic-related PM2.5 exacerbated allergic conjunctivitis as evidenced by increased infiltration of inflammatory cells into the conjunctiva and Th2 responses in the draining LNs associated with enhanced maturation of DCs. Our findings provide new insight into the hazardous potential of traffic-related PM2.5 on allergic diseases, such as asthma or atopic dermatitis.

Developing sensing approaches that can exploit visible light for the detection of low-concentration hydrogen at room temperatures has become increasingly important for the safe use of hydrogen in many applications. In this study, heterostructures composed of monolayer MoS2 and Pd nanoclusters (Pd/MoS2) acting as photo- and hydrogen-sensitizers are successfully fabricated in a facile and scalable manner. The uniform deposition of morphologically isotropic Pd nanoclusters (11.5 ± 2.2 nm) on monolayer MoS2 produces a plethora of active heterojunctions, effectively suppressing charge carrier recombination under light illumination. The dual photo- and hydrogen-sensitizing functionality of Pd/MoS2 can enable its use as an active sensing layer in optoelectronic hydrogen sensors. Gas-sensing examinations reveal that the sensing performance of Pd/MoS2 is enhanced three-fold under visible light illumination (17% for 140 ppm of H2) in comparison with dark light (5% for 140 ppm of H2). Photoactivation is also found to enable excellent sensing reversibility and reproducibility in the obtained sensor. As a proof-of-concept, the integration of Pd nanoclusters and monolayer MoS2 can open a new avenue for light-induced hydrogen gas sensing at room temperature.

Pt is the most commonly used electrode and catalyst materials for H2 production via water splitting as it provides the highest Gibbs free energy of H2 adsorption (ΔGH) an d overpotential. However, as Pt catalysts are expensive and difficult to mass-produce, several efforts have been made to identify suitable substitutes. Although Cu provides lower ΔGH and overpotential than Pt, it exhibits better catalytic performance than other catalysts and is suitable for H2 production. However, corrosion of Cu may affect its stability of Cu electrode. To overcome this limitation, we have coated a layer of carbon on the copper electrode and then synthesized titanium dioxide-(TiO2-) on the C/Cu electrode for water splitting application. Carbon black (CB) has excellent electrical conductivity and stable resistance for effective working as an electrochemical catalyst, and TiO2 has diverse applications because of its low-cost, non-toxic, and corrosion-resistant characteristics. In this study, TiO2 was synthesized on C/Cu electrodes under UV irradiation for different durations. The optimum irradiation duration was determined to be 15 min via surface and electrochemical analyses. To identify the potential applications of this TiO2–C/Cu electrode, we used artificial wastewater as the electrolyte. The synthesized TiO2–C/Cu electrode exhibited better stability than C/Cu electrode. Further, H2 production with TiO2–C/Cu electrode was higher than that with C/Cu electrode at the same current density. We also investigated the effect of TiO2–C/Cu electrode on decomposition of formaldehyde.

Titanium oxide (TiO2) has received growing attention in photocatalyst is owing to its chemical stability and ecofriendly nature. Among the different phases of TiO2, pure anatase and mixed-phase TiO2 (Degussa P25) have been recognized as superior photocatalysts. Indeed, the mechanism of photocatalysis and the roles of various parameters in the process have been well documented for pure anatase TiO2 and Degussa P25. However, the pure rutile phase remains unexplored in the context of photocatalytic applications. Thus, herein, we report a one-pot method to modify the surface of pure rutile TiO2 and examine the factors that affect its photocatalytic performance. This modification was achieved by treating rutile TiO2 with H2O2 under microwave irradiation, which led to the formation of core-shell rutile TiO2 with a crystalline core and an amorphous shell bearing Ti3+ and Ti–OH species on the surface. The photocatalytic performance of this modified TiO2 species was enhanced threefold compared with that of unmodified rutile TiO2. This basic understanding of how to improve the photocatalytic performance of rutile phase TiO2 will play a crucial role in enhancing the catalytic performance of other metal oxides.

Water splitting from wastewater has been in the limelight because it has advantages which are hydrogen production and electrochemical oxidation at the same time. For efficient water splitting even in wastewater condition, water splitting electrodes should have cost-effectiveness and high durability. Here, we fabricated highly stable and electrocatalytic graphene on copper-nickel alloy to electrochemically produce hydrogen from wastewater in presence of carbon layer between nickel and copper. The electrode fabrication was performed by alloying the copper with nickel and growing graphene on the surface at the same time. The copper and nickel contents of electrode surface were kept by carbon layer hindering the metal diffusion at high temperature. Highly electrocatalytic activity (onset potential = 95 and 158 mV, Tafel slope = 58 and 80 mV dec−1), high durability and pH independence of graphene on copper-nickel alloy were confirmed in acidic and alkaline wastewater containing formaldehyde.

Long-term exposure to fine particles (PM

Volatile organic compounds (VOCs) emitted to the atmosphere form ozone and secondary organic aerosols (SOA) by photochemical reactions. As they contain numerous harmful compounds such as carcinogens, it is necessary to analyze them from a health perspective. Given the petroleum-based organic solvents used during the drying process, large amounts of VOCs are emitted from small laundry facilities. In this study, a laundry facility located in a residential area was selected, while VOCs data emitted during the drying process were collected and analyzed using a thermal desorption-gas chromatography/mass spectrometer (TD-GC/MS). We compared the results of the solvent composition, human risk assessment, contribution of photochemical ozone creation potential (POCP), and secondary organic aerosol formation potential (SOAP) to evaluate the chemical species. Alkane-based compounds; the main components of petroleum organic solvents, were dominant. The differences in evaporation with respect to the boiling point were also discerned. The POCP contribution exhibited the same trend as the emission concentration ratios for nonane (41%), decane (34%), and undecane (14%). However, the SOAP contribution accounted for o-xylene (28%), decane (27%), undecane (25%), and nonane (9%), thus confirming the high contribution of o-xylene to SOA formation. The risk assessment showed that acrylonitrile, carbon tetrachloride, nitrobenzene, bromodichloromethane, and chloromethane among carcinogenic compounds, and bromomethane, chlorobenzene, o-xylene, and hexachloro-1, 3-butadiene were found to be hazardous, thereby excessing the standard value. Overall these results facilitate the selection and control of highly reactive and harmful VOCs emitted from the dry-cleaning process.

MoS2 has been widely researched as a good catalyst for the hydrogen production, however, the electrochemical applications of MoS2 are still limited because of its low electrical conductivity and electrochemically inert basal plane. In this study, hybrids of MoS2 and MoO2 were used to decrease charge transfer resistance of electrodes. The proportions of MoS2 and MoO2 were controlled by soft annealing without a structural change. The coexistence of MoS2−MoO2 was confirmed by Raman and X-ray diffraction analysis, and the change of chemical compositions (MoS2 to MoO2 ratio) were demonstrated by X-ray photoelectron spectroscopy. By controlling the chemical compositions of MoS2 and MoO2, the optimal ratio of MoS2 and MoO2 (3: 1) showed the highly electrocatalytic activity (η10: 198 mV, Tafel: 66.8 mV dec−1) and outstanding long-term stability compared to other ratios of MoS2 and MoO2.

In this study, we synthesized platinum (Pt) nanoparticles (NPs) loaded onto three-dimensional (3D) graphene for hydrogen (H2) sensing using a polymer-assisted hydrothermal (HT) method. The highly porous Pt-3D graphene configuration was sufficiently stable to avoid collapsing during synthesis. It was then deposited onto a microheater to fabricate a H2 sensor. The resulting H2 sensor had high sensitivity, fast response/recovery, less hysteresis, and good linearity.

In recent years, fossil fuel depletion has been increasing, which leads to environmental issues. Hydrogen energy is considered a promising renewable energy to replace fossil fuels because it is a sustainable, clean, and green energy source. Among hydrogen production methods, water splitting has the highest reliability and is used the most often. Platinum is normally used as water splitting catalyst and an electrode. However, there has been much effort to replace it as such owing to its high cost. Copper (Cu) is not used as water splitting catalyst or an electrode, despite its high current density, because of its corrosive properties. In this study, carbon was coated onto a Cu substrate and a hydrogen production experiment was carried out with 0.1 M Na 2 SO 4 and 0.1 M H 2 SO 4 electrolytes. As a result, the carbon coating decreased oxidation rate of the Cu electrode and effected stability in short-term hydrogen evolution experiment. This indicates the possibility of carbon-Cu electrode with other catalytic materials.

This study attempted to reanalyze the emission property of particulate matter and set up the strategy on the emission reduction of particulate matter by considering the condensable particulate matt...

Ni/spent FCC catalyst was applied as the catalyst on the catalytic pyrolysis and gasification of yellow poplar (YP). Larger amount of gas (CO, CO₂, H₂, C1~C₄) was produced by applying Ni/spent FCC catalyst to the catalytic pyrolysis and gasification of YP. Ni/spent FCC catalyst also increased the selectivity of phenols and aromatic hydrocarbons in oil product during the pyrolysis and gasification of YP. Overall catalytic performance of Ni/spent FCC catalyst was similar level with that of Ni/γ-Al₂O₃, suggesting its potential use.

A layered germanium phosphide (GeP3) was synthesized in a straightforward manner using a simple solid-state synthetic method, and its electrochemical behavior for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) was investigated. During Li-insertion and extraction, the GeP3 experienced a sequential three-step (topotactic-transition, conversion, and alloying) and two-step (dealloying and recombination) reaction. During Na-insertion and extraction, GeP3 had a one-step (conversion) and two-step (recombination and topotactic-transition) reaction. Based on the interesting phase change mechanisms during Li- and Na-insertion/extraction, the GeP3–based nanocomposite exhibited superior electrochemical performance, such as large reversible capacity (first reversible capacity: 1526 mAh g-1 for LIB, 984 mAh g-1 for SIB), high initial Coulombic efficiencies (86.3% for LIB, 81.3% for SIB), stable cycle life (capacity retention for LIB: 95% in 0–2 V after 30 cycles, 87% in 0.35–2 V after 100 cycles, and 93% in 0.64–2 V after 100 cycles, capacity retention for SIB: 95% in 0–2 V after 30 cycles), and rapid rate-capabilities (LIB: 860 mAh g-1 in 0.35–2 V at 2C-rate, SIB: 520 mAh g-1 in 0–2 V at 2C-rate). Overall, the layered GeP3–based anode with its interesting Li- and Na-reaction mechanisms will be a promising alternative anode for high-performance LIBs and SIBs.

Acetaldehyde removal tests were performed to compare the catalytic activity of the Kraft lignin char (KC), KOH-treated Kraft lignin char (KKC), and activated carbon (AC) along with their impregnation with Mn in a plasma reactor. The gasification characteristics (syngas content, and H2/CO ratio) of yellow poplar were investigated using nickel catalysts supported on KC, KKC, AC, and γ-Al2O3 in a U-type quartz reactor. KKC and Mn/KKC improved significantly the surface area and contents of O and N functional groups over the raw char. In particular, Mn/KKC showed the highest acetaldehyde-removal efficiency. The catalytic activity of Ni-impregnated KC, KKC, AC, and γ-Al2O3 decreased in the order of Ni/KKC > Ni/AC > Ni/KC > Ni/γ-Al2O3 for the gas yield and Ni/γ-Al2O3 >Ni/KC > Ni/AC >Ni/KKC for the oil yield, respectively. The Ni/KKC provides a more conducive environment for gasification, resulting in larger amounts of syngas (H2 and CO) in the product gases. Moreover, Ni impregnated with char may be the most inexpensive and effective solution for achieving maximum tar reduction and syngas generation.

A practical application of graphene is in transistors and diodes fabricated through processes compatible with integrated circuit fabrication processes that are currently used. In this paper, a highly controlled gas phase fluorination treatment (using XeF2) of an intrinsic Si-terminated SiC (i-SiC) substrate and a (6√3ⅹ6√3)R30° carbon buffer layer is shown to effectively convert the buffer layer to p-doped SLG (p-SLG), which is decoupled from the i-SiC substrate through F intercalation. The electrical properties of two diode structures, (1) metal/SiC with buffer layer and (2) p-SLG/SiC, were investigated considering the bias-dependent carrier injection at each interface. The analysis results suggest that the diode turn-on for each diode is due to carrier injection from the metal or p-SLG to the i-SiC substrate, with an exponential modulation of the thermionic injection driven by the image barrier lowering effect. A complementary SLG-based SiC diode formation scheme is demonstrated, as hole injection from p-SLG is the origin of positive bias diode turn-on in the second diode type, whereas the diode having metal/SiC with buffer structure showed negative bias turn-on.

For the sustainable clean and green energy, hydrogen is considered as one of the prominent renewable energy source which attracted increasing interests in recent years. To produce this, one of the cheapest method is water electrolysis. But several challenges in water electrolysis are, to reduce the maintenance cost, energy consumption and high cost of platinum electrode material. So, in search of an alternative low cost and efficient electrode material, researchers are modifying various metals electrodes to replace the noble metal electrodes. Stainless steel (SS 304) is one of the types of carbon steel material commonly used for various applications. The aim of the work is to explore the stainless steel (SS 304), annealed at high temperature, with and without “hydrogen and argon” environment and tested the samples for hydrogen production in sea water condition (3.5% NaCl). Cr2O3 and MnCr2O4 spinel oxide formation was observed over the surface of the electrodes after annealing process. From Raman, X-ray Photoelectron Spectroscopy (XPS) and electrochemical measurements it was observed that, the sample prepared under hydrogen and argon environment is stable when compared with the rest of the samples. Decrease in relative amount of chromium oxide was observed for the sample annealed in air environment. The rate of production of hydrogen prepared under “hydrogen and argon” environment is higher and the results are discussed.

The lacking of laboratory black carbon (BC) samples have long challenged the corresponding toxicological research, furthermore, the toxicity tests of engineered carbon nanoparticles were unable to reflect atmospheric BC. As a simplified approach, we have synthesized artificial BC (aBC) for the purpose of representing atmospheric BC. Surface chemical properties of aBC were controlled by thermal treatment, without transforming its physical characteristics, thus, we were able to examine the toxicological effects on A549 human lung cells arising from aBC with varying oxidation surface properties. X-ray photoelectron spectroscopy, as well as Raman and Fourier transform infrared spectroscopy, verified the presence of increased amounts of oxygenated functional groups on the surface of thermally-treated aBC, indicating aBC oxidization at elevated temperatures, aBC with increased oxygen functional group content displayed increased toxicity to A549 cells, specifically by decreasing cell viability to 45% and elevating reactive oxygen species levels up to 294% for samples treated at 800 °C.

This study examines environmental impact assessment considering filterable particulate matter (FPM) and condensable particulate matter (CPM) to improve the accuracy of the air quality model. Air pollutants and meteorological data were acquired from Korea’s national monitoring station near a residential development area in the target district and background site. Seasonal emissions of PM2.5, including CPM, were estimated using the California puff (CALPUFF) model, based on Korea’s national emissions inventory. These results were compared with the traditional environmental impact assessment results. For the residential development area, the seasonal PM2.5 concentration was predicted by considering FPM and CPM emissions in the target area as well as the surrounding areas. In winter and spring, air quality standards were not breached because only FPM was considered. However, when CPM was included in the analysis, the results exceeded the air quality standards. Furthermore, it was predicted that air quality standards would not be breached in summer and autumn, even when CPM is included. In other words, conducting an environmental impact assessment on air pollution including CPM affects the final environmental decision. Therefore, it is concluded that PM2.5 should include CPM for greater accuracy of the CALPUFF model for environmental impact assessment.

Developing sensing approaches that can exploit visible light for the detection of low-concentration hydrogen at room temperatures has become increasingly important for the safe use of hydrogen in many applications. In this study, heterostructures composed of monolayer MoS

In this study, we examined tire and road wear microparticles (TRWMPs) in road dust along the Seoul metropolitan area, from industrial and residential areas. The road dust samples were collected via vacuum sweep methods and then filtered to obtain particles with diameters less than 75 μm. To quantify the TRWMPs in road dust, we used the raw materials of tire components, natural rubber (NR), and styrene–butadiene rubber (SBR), as standard materials. We evaluated the usability of the pyrolyzer-gas chromatography/mass spectrometry py-GC/MS method introduced in ISO/TS 20593 by confirming the decomposition temperatures of the NR and SBR by thermogravimetric (TG) and evolved gas analysis (EGA)-MS. The average of TRWMPs in industrial and residential area road dust were 22,581 and 9818 μg/g, respectively, indicating that the industrial area has 2.5 times higher TRWMPs concentration. Further, the NR, the main component of truck bus radial, to SBR, the main component of passenger car radial, ratio was slightly higher in the industrial area than in the residential area. This presumably means that the high traffic volume, including heavy duty vehicles in industrial areas, affected the higher concentration of TRWMPs. This study reveals the growing evidence of the importance of TRWMPs in road dust and how TRWMPs quantity can impact the air quality of the Seoul metropolitan area.

Water splitting is one of the efficient ways to produce hydrogen with zero carbon dioxide emission. Thus far, Pt has been regarded as a highly reactive catalyst for the hydrogen evolution reaction (HER); however, the high cost and rarity of Pt significantly hinder its commercial use. Herein, we successfully developed an HER catalyst composed of NiSx (x = 1 or 2) on stainless steel (NiSx/SUS) using electrodeposition and sulfurization techniques. Notably, the electrochemical active surface area(ECSA) of NiSx/SUS was improved more than two orders of magnitude, resulting in a considerable improvement in the electrochemical charge transfer and HER activity in comparison with stainless steel (SUS). The long-term HER examination by linear scan voltammetry (LSV) confirmed that NiSx/SUS was stable up to 2000 cycles.

Here, we develop a dry eye syndrome (DES) incidence rate prediction model using air pollutants (PM10, NO2, SO2, O3, and CO), meteorological factors (temperature, humidity, and wind speed), population rate, and clinical data for South Korea. The prediction model is well fitted to the incidence rate (R2 = 0.9443 and 0.9388, p &lt, 2.2 &times, 10&minus, 16). To analyze regional deviations, we classify outpatient data, air pollutant, and meteorological factors in 16 administrative districts (seven metropolitan areas and nine states). Our results confirm NO2 and relative humidity are the factors impacting regional deviations in the prediction model.

Air pollution caused by particulate matter (PM) has become a serious issue, and significant research has focused on managing large stationary emission sources, i.e., the primary sources of PM. Currently, the U.S. Environmental Protection Agency (EPA) Method 201A and ISO 23210 are predominantly employed to measure the PM emissions at large stationary sources. Method 201A is designated as a standard test method in Korea, but it is difficult to measure PM

A layered germanium telluride (GeTe) and its C-modified nanocomposite (GeTe–C) are synthesized by a simple solid-state synthesis technique, and their electrochemical behaviors for rechargeable lithium-ion batteries (LIBs) are evaluated. Various ex situ analytical tools are employed to demonstrate the electrochemical Li-insertion/-extraction mechanisms of the electrodes. GeTe during Li-insertion exhibits two-step conversion/alloying reactions, and does not recombine after Li-extraction. Interestingly, although GeTe–C shows the same two-step conversion/alloying reactions during Li-insertion, Ge and Te fully recombine after Li-extraction. Owing to the full recombination reactions by the ongoing Li-cycling, GeTe–C shows excellent electrochemical Li-ion storage performances, such as highly reversible capacities (1st Li-insertion/-extraction capacity: 841/691 mA h g−1 or 1767/1450 mA h cm−3), extremely rigid cycling durability (capacity retention: 97.8% after 100 cycling), and rapid rate-capabilities (940 mA h cm−3 at 3C-rate). Therefore, the GeTe–C modified with layered GeTe and amorphous C is a promising anode material with a high energy density for high-performance LIBs.

Ambient particulate matter (PM), a major component of air pollution, aggravates ocular discomfort and inflammation, similarly to dry eye disease (DED) or allergies. However, the mechanism(s) by which PM induces the ocular inflammatory response is unknown. This study investigated the immunological response of traffic-related fine particulate matter (PM2.5) on the ocular surface in a murine model. C57BL/6 mice were exposed by topical application to PM2.5 or vehicle for 14 days to induce experimental environmental ocular disease. Corneal fluorescein staining and the number of ocular inflammatory cells were assessed in both groups. The expression of IL-1&beta, IL-6, tumor necrosis factor (TNF)-&alpha, and mucin 5AC (MUC5AC) in the ocular surface were evaluated by real-time PCR. An immunohistochemical assay evaluated apoptosis and goblet cell density. ELISA was used to determine the levels of serum IgE and cytokines of Type 1 helper (Th1) and Type 2 helper (Th2) cells after in vitro stimulation of T cells in the draining lymph nodes (LNs). Exposure to traffic-related PM2.5 significantly increased corneal fluorescein staining and cellular toxicity in the corneal epithelium compared with the vehicle control. A significant increase in the number of CD11b+ cells on the central cornea and mast cells in the conjunctiva was observed in the PM2.5 group. Exposure to PM2.5 was associated with a significant increase in the corneal or conjunctival expression of IL-1&beta, IL-6, TNF, and MUC5AC compared to the vehicle, and increased maturation of dendric cells (DCs) (MHC-IIhighCD11c+) in draining LNs. In addition, PM2.5 exposure increased the level of serum IgE and Th2 cytokine production in draining LNs on day 14. In conclusion, exposure to traffic-related PM2.5 caused ocular surface damage and inflammation, which induced DC maturation and the Th2-cell-dominant allergic immune response in draining LNs.

An attempt to optimize Zn2SnO4 (ZTO) thin film has been done by alternate thermal evaporation of ‘Sn’ and ‘Zn’ in the sequence Sn10/Zn15/Sn15/Zn15/Sn5 onto corning glass substrates and subsequent post oxidation process. The XRD patterns of as-deposited metallic thin films changed over from metallic to oxidized ZTO phase with cubic spinel structure along with ZnO phase. The film thickness and roughness increased apparently due to diffusion of oxygen into the metallic inter-layers. The binding energies estimated from the XPS data also indicated oxidation of the metallic multi-layers. Post-annealing of the film developed transparency in visible region to around 40%. The direct band gap of ZTO and ZnO were estimated to be 3.46 eV and 3.10 eV respectively. The annealed ZTO thin film was measured for electrical transport parameters by Hall Effect measurement. Raman spectrum observed at 668 cm−1 is due to stretching vibration of short metal-oxide bonds in the MO6 octahedron. The photoluminescence spectrum showed blue emission centered around 436 nm predominantly due to oxygen vacancies in addition to weak orange emission centered at 625 nm. Gas sensor using thin films of as-deposited and ZTO formed by post-annealing process showed significant sensing response for NO2 gas. These results reveal that the ZTO thin film deposited by alternate thermal evaporation and subsequent post oxidation is worth exploring as transparent conducting electrode and also as a gas sensing material.

We developed equations for nano-sized titanium dioxide (TiO2) particles self preserving time (SPT) lag that combines with agglomerate key parameters such as primary particle size (PPS), geometric standard deviation (GSD) and mass fractal dimension (MFD). A statistical formula has been developed that relies on SPT lag as the key parameter of agglomerates. Finally, this research presents the first analytical solution by integrating these key parameters into one formula, which can be utilized as a handy tool to calculate the time for reaching the asymptotic state.

Formaldehyde (H2CO) is the harmful chemical that used in variety of industries. However, there are many difficulties to treat discharged H2CO in the wastewater. Hydrogen energy is arising as a one of the renewable energy that can replace fossil fuel. Many researches have been conducted on hydrogen production from electrolysis using expensive metal electrodes and catalysts such as platinum (Pt) and palladium (Pd). However, they are expensive and have obstacles to directly use from the production. We used copper (Cu) as an electrode substrate because it has a good current density. To avoid corrosion issue of Cu substrate, we used commercially available carbon (C) coated Cu substrate and synthesized titanium (Ti) on C/Cu substrate. We found that Ti was well synthesized and stayed on substrate after hydrogen evolution reaction (HER) in artificial wastewater. Moreover, we quantified hydrogen production from the wastewater and compared it to pure water. Hydrogen production was enhanced in wastewater and H2CO was decomposed after reaction. We expected to use Ti-C/Cu electrode for hydrogen production of wastewater by electrolysis.

H 2 evolution from photocatalytic decomposition by liquid phase plasma was examined over Ag-loaded photocatalysts. The effect of methanol addition into water was estimated in the photocatalytic water splitting. Photocatalytic activity of perovskite was also assessed in the photocatalytic water splitting. H 2 was evolved in the photocatalytic splitting of water by reacting of active species. The photocatalytic activity for H 2 generation of TiO 2 prepared by sol-gel method was higher than that of commercial TiO 2 photocatalyst. The rate of H 2 evolution was progressed with Ag loading on TiO 2 photocatalysts. The addition of methanol into water brought to a significant enhancement of H 2 evolution. The methanol acted as an electron donor to increase the amount of H 2 production.

To use the microwave/ML/TiO 2 hybrid system as an advanced treatment of nitrobenzene (NB), a series of experiments were performed to examine the effects of microwave irradiation and auxiliary oxidants. The degradation of NB was carried out using different combinations of five-unit treatment techniques. The NB degradation rate increased with increasing microwave intensity. The circulation fluid velocity, concentration of H 2 O 2 , and the rate of O 2 gas injection showed the highest rate of degradation under optimal conditions. A significant synergistic effect was observed when H 2 O 2 addition was combined with the microwave/ML/TiO 2 hybrid process.

We report a facile and effective low-temperature modification method for improving the photocatalytic activity of commercial Degussa P25 TiO2. The method involves the microwave treatment of TiO2 in an H2O2 solution. The properties of the modified TiO2, including improved crystallinity, size distribution, and aggregation of the anatase/rutile phases, were analyzed by X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscope (TEM). Further, we found that Ti3+ and Ti-OH were formed because of the presence of H2O2. Moreover, the valence band (VB) edge was determined by Raman and X-ray photoelectron spectroscopy (XPS) studies. In addition, photoluminescence (PL) measurements showed that the surface defects in the modified P25 affected the hole–electron recombination rate. UV–vis spectroscopy measurements show various size distribution and band gap effects after the simple modification process, and the photocatalytic activity was determined using the degradation of Rhodamine 6G (R6G). From these results, the degradation efficiency under solar and UV irradiation were measured to be 94 and 51% for modified P25 and be 47 and 25% for unmodified P25, respectively. The modified P25 showed twice the photocatalytic performance of the unmodified P25. The enhancement in the photocatalytic efficiency of modified P25 is correlated to the formation of surface defects, such as Ti3+ and Ti-OH, the size distribution, and the re-aggregation of the anatase/rutile phases.

Herein, we describe a simple solid-state synthesis of zinc sulfide (ZnS) and its amorphous carbon–modified nanocomposite (ZnS/C) and examine their performance as high-capacity anode materials for rechargeable Li-ion batteries, probing lithiation/delithiation mechanisms by ex situ X-ray diffraction and extended X-ray absorption fine structure analyses. The ZnS converted into LiZn and Li2S during lithiation, being subsequently incompletely recombined into ZnS during delithiation and thus resulting in traces of Zn and S. Based on the above investigation of reaction mechanism, the ZnS/C electrode was electrochemically tested within a potential range of 0–2.0 V vs. Li+/Li and exhibited a high reversible capacity of 681 mAh g−1, excellent cycling stability (>150 cycles), and high rate capability.

The rapid development of modern industry has resulted in increased emissions of nitrogen dioxide gas in recent decades. In order to develop ubiquitous environmental monitoring system suitable for the Internet of Things (IoT) paradigm, the high-sensitivity and fast-response detection of NO 2 gas at low concentrations is of particular importance. Recently, two-dimensional (2D) materials have shown fast response/recovery characteristics in the detection of NO 2 , due to their planar crystal structures, large surface-to-volume ratios, and low electronic noise. Among these materials, tin disulfide has shown superior sensing performances, at the parts-per-million (ppm) level, in addition to fast response and good stability. Therefore, here we report the synthesis of 2D SnS 2 materials via high-energy ball milling (HEBM), followed by characterization of the crystal structures and morphologies of the products by X-ray diffraction and transmission electron microscopy. The use of the present SnS 2 nanomaterial as a NO 2 sensor enables the detection of a wide range of gas concentrations (from parts-per-billion (ppb) to ppm levels) with fast response and high sensitivity, at an optimal operating temperature of 250 °C. Under these conditions, the sensor exhibited a response >2000% and response/recovery times of 6/40 s at an NO 2 concentration of 10 ppm. Finally, the sensor developed in this work also produced highly repeatable and linear responses.

Hydrogen is one of the most promising alternative energy resources of fossil fuels. Among the many ways to generate hydrogen gas, electrochemical water splitting is more feasible and renewable. Compared to processes using solar energy for a specific geological environment or thermochemical decomposition at high temperatures, the electrocatalysis of water can produce hydrogen without the restriction of geological conditions and scale-up facilities. Water is one of the most renewable and sustainable resources to obtain hydrogen. On the other hand, water splitting into hydrogen and oxygen is thermodynamically unfavorable under the atmospheric condition. Therefore, novel materials are needed to produce hydrogen from water splitting using electrocatalysts. Recently, various state-of-the-art technologies and catalysts have been developed in the electrocatalysis of water to produce hydrogen. Among the litany of novel materials, according to the preparation method and morphology of electrocatalysts, the hydrogen production efficiency from water splitting shows great differences. This paper recently reported efficient electrocatalysts for water splitting using multi-component catalysts composed of several metals, organic polymer, metal sulfides, and metal phosphides. In addition, the essential principles for an investigation regarding more efficient hybrid electrocatalysts for water splitting as a renewable and sustainable hydrogen producing method can be determined.

A simple, inexpensive, and scalable method for transforming phosphorous pentoxide (P2O5) into black phosphorus (BP)-based composites was developed. The BP-based composites of BP@MgO, BP@Al2O3, and BP@TiO2 synthesized by a one-pot mechanochemical reduction of P2O5 using Mg, Al, or Ti were composed of nanocrystalline BP within the metal oxide matrices of MgO, Al2O3, or TiO2, respectively. Subsequently, the potential of these composites as anode materials in rechargeable Li-ion batteries (LIBs) was investigated. BP@TiO2 showed the highest electrochemical performance among the BP-based composites. Specifically, the BP@TiO2 exhibited a high reversible capacity over 510 mAh g−1 after 300 cycles and a fast rate capability of ~ 400 mAh g−1 at the 3C rate. The superior electrochemical performance of BP@TiO2 was attributed to the well-dispersed nanocrystalline BP and the Li-reactive TiO2 matrix. Additionally, the formation of LixTiO2 in the Li-reactive TiO2 matrix during Li cycling increased the electrochemical Li-ion conductivity and diffusivity, contributing to the enhanced electrochemical performance. Therefore, the BP@TiO2 synthesized by the one-pot mechanochemical reduction has high potential as a superior LIB anode.

Two-dimensional quantum dots (2D QDs) comprising PtS2 with low Pt loading (0.002 wt.%) distributed on a distinctive CVD-grown titanium carbide substrate (PtS2/TiC) was successfully synthesized and employed for a hydrogen evolution reaction (HER). Notably, despite the low loading of the former component, PtS2/TiC showed excellent HER activity with a superior overpotential (55 mV at 10 mA/cm−2) to that of commercial Pt/C (50 mV at 10 mA/cm−2). The Faraday efficiency of PtS2/TiC was found to be 92.5 %, revealing the superior properties of hydrogen production. The In-situ Raman spectra reveal the important role of S atoms in PtS2 as the active sites for HER, as evidenced by S H bonding formation at 2532 cm-1 during the HER process. This study provides a fundamental understanding essential for the design of more efficient catalysts in the field of electrochemical applications.

Carbon black (CB) is an inexpensive and widely used carbonaceous material. However, the reversibility between CB and Li or Na is very poor, and the initial coulombic efficiency (ICE) is so low that it cannot be used as an electrode material for rechargeable batteries. In this study, we successfully designed superior CB as a high-performance conducting additive for Li-ion batteries (LIBs) and Na-ion batteries (NIBs) using a simple two-step strategy: amorphization and pre-lithiation/sodiation. The Li- and Na-reversible capacities of amorphized CB increased significantly from 213 to 564 mAh g−1 for LIB and from 92 to 209 mAh g−1 for NIB; however, the corresponding ICEs of 61.5% for LIB and 33.5% for NIB are poor. The poor ICEs are supplemented via pre-lithiation/sodiation in the amorphized CB, which show over 100% ICEs with high Li- and Na-reversible capacities. Specifically, the modified CB has highly reversible capacities (>500 mAh g−1 for LIB, >300 mAh g−1 for NIB) with exceptionally high ICEs (133% ICE for LIB, 160% ICE for NIB), stable reversible capacities for over 100 cycles (470 mAh g−1 for LIB, 278 mAh g−1 for NIB), fast rate capabilities with highly reversible capacities at a 3C rate (~330 mAh g−1 for LIB, ~190 mAh g−1 for NIB), and excellent cycling behavior for over 300 cycles at a 1C rate. When used as a conducting additive, this CB contributes to high electrical conductivity and increase of ICE and the reversible capacity for LIB and NIB anode materials. These results are expected to have a significant impact on LIBs and NIBs.