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The increase in impervious areas caused by urbanization causes the amount of surface rainfall-runoff and nonpoint source (NPS) pollutant discharge to also increase. This issue has sparked a growing interest in low impact development (LID) technology and NPS reduction technology. The objective of this study is to analyze the ability of a hybrid system to achieve both rainfall-runoff and NPS pollutant reduction simultaneously. The results indicate that this system is effective in reducing particulate matter with a relatively small particle size (less than 64 μm), which plays an important role in reducing NPS pollution. It is expected that a LID-based urban water cycle recovery policy could be established through further research on various hybrid system configuration methods and socioeconomic effect analysis.

In capacitive deionization, the salt-adsorption capacity of the electrode is critical for the efficient softening of brackish water. To improve the water-deionization capacity, the carbon electrode surface is modified with ion-exchange resins. Herein, we introduce the encapsulation of zwitterionic polymers over activated carbon to provide a resistant barrier that stabilizes the structure of electrode during electrochemical performance and enhances the capacitive deionization efficiency. Compared to conventional activated carbon, the surface-modified activated carbon exhibits significantly enhanced capacitive deionization, with a salt adsorption capacity of ∼2.0 × 10–4mg/mL and a minimum conductivity of ∼43 μS/cm in the alkali-metal ions solution. Encapsulating the activated-carbon surface increased the number of ions adsorption sites and the surface area of the electrode, which improved the charge separation and deionization efficiency. In addition, the coating layer suppresses side reactions between the electrode and electrolyte, thus providing a stable cyclability. Our experimental findings suggest that the well-distributed coating layer leads to a synergistic effect on the enhanced electrochemical performance. In addition, density functional theory calculation reveals that a favorable binding affinity exists between the alkali-metal ion and zwitterionic polymer, which supports the preferable salt ions adsorption on the coating layer. The results provide useful information for designing more efficient capacitive-deionization electrodes that require high electrochemical stability.

Platinum-based metal alloys have been generally developed to provide high carbon monoxide resistance in the anodes of direct methanol fuel cells. We report the potential of bimetallic platinum/iridium electrocatalysts in preserving the outstanding carbon monoxide tolerance obtained from both experimental and theoretical studies, which represents the enhanced electrochemical performance of methanol oxidation and the in-depth and stepwise investigations for reaction mechanisms, respectively. In this study, the findings highlight the dual-enhancement characteristics of low carbon monoxide adsorption energy (electronic effect) and carbon monoxide oxidative removal (bifunctional effect) compared with various electrocatalysts such as platinum, iridium, and platinum/ruthenium alloys. In addition, the reaction affinity of platinum/iridium alloys for methanol dehydrogenation is also studied in accordance with atomistic properties, such as adsorption energy and electronic band gap, to understand the electrochemical performance compared to Pt. The results obtained indicate that the platinum/iridium alloy surface played diverse roles in terms of its multifunctional behaviors for carbon monoxide tolerance, including the favorable mechanism of methanol dehydrogenation. It turns out that throughout the theoretical in-depth studies, platinum/iridium alloys are promising candidates in terms of the extension for electrocatalytic material designs that differ from Ru in direct methanol fuel cells.

Recently, holographic display and computer-generated holograms calculated from real existing objects have been more actively investigated to support holographic video applications. In this paper, we proposed a method of generating 360-degree color holograms of real 3D objects in an efficient manner. 360-degree 3D images are generated using the actual 3D image acquisition system consisting of a depth camera and a turntable and intermediate view generation. Then, 360-degree color holograms are calculated using a viewing-window-based computer-generated hologram. We confirmed that floating 3D objects are faithfully reconstructed around a 360-degree direction using our 360-degree tabletop color holographic display.

Since adsorption performances are dominantly determined by adsorbate–adsorbent interactions, accurate theoretical prediction of the thermodynamic characteristics of gas adsorption is critical for designing new sorbent materials as well as understanding the adsorption mechanisms. Here, through our molecular modeling approach using a newly developed quantum-mechanics-based force field, it is demonstrated that the CO2adsorption selectivity of SBA-15 can be enhanced by incorporating crystalline potassium chloride particles. It is noted that the induced intensive electrostatic fields around potassium chloride clusters create gas-trapping sites with high selectivity for CO2adsorption. The newly developed force field can provide a reliable theoretical tool for accurately evaluating the gas adsorption on given adsorbents, which can be utilized to identify good gas adsorbents.

For efficient solar cells based on organic semiconductors, a good mixture of photoactive materials in the bulk heterojunction on the length scale of several tens of nanometers is an important requirement to prevent exciton recombination. Herein, we demonstrate that nanoporous titanium dioxide inverse opal structures fabricated using a self-assembled monolayer method and with enhanced infiltration of electron-donating polymers is an efficient electron-extracting layer, which enhances the photovoltaic performance. A calcination process generates an inverse opal structure of titanium dioxide (<70 nm of pore diameters) providing three-dimensional (3D) electron transport pathways. Hole-transporting polymers was successfully infiltrated into the pores of the surface-modified titanium dioxide under vacuum conditions at 200 °C. The resulting geometry expands the interfacial area between hole- and electron-transport materials, increasing the thickness of the active layer. The controlled polymer-coating process over titanium dioxide materials enhanced photocurrent of the solar cell device. Density functional theory calculations show improved interfacial adhesion between the self-assembled monolayer-modified surface and polymer molecules, supporting the experimental result of enhanced polymer infiltration into the voids. These results suggest that the 3D inverse opal structure of the surface-modified titanium dioxide can serve as a favorable electron-extracting layer in further enhancing optoelectronic performance based on organic or organic–inorganic hybrid solar cell.

A stable electrolyte is required for use in the open-packing environment of a Li-O2battery system. Herein, a gelled quasi-solid-state electrolyte containing SiO2nanoparticles was designed, in order to obtain a solidified electrolyte with a high discharge capacity and long cyclability. We successfully fabricated an organic–inorganic hybrid matrix with a gelled structure, which exhibited high ionic conductivity, thereby enhancing the discharge capacity of the Li-O2battery. In particular, the improved electrochemical stability of the gelled cathode led to long-term cyclability. The organic–inorganic hybrid matrix with the gelled structure played a beneficial role in improving the ionic conductivity and long-term cyclability and diminished electrolyte evaporation. The experimental and theoretical findings both suggest that the preferential binding between amorphous SiO2and polyethylene glycol dimethyl ether (PEGDME) solvent led to the formation of the solidified gelled electrolyte and improved electrochemical stability during cycling, while enhancing the stability of the quasi-solid state Li-O2battery.

Carbon dioxide reforming of methane has attracted much attention as an energy production process to generate energy sources such as hydrogen and more importantly, carbon monoxide, so called syn-gas. Because carbon deposition and sintering of particles on a catalyst limit its practical application for CO2reforming of CH4. Steam pre-treatment was performed on MgO promoted NiCo/Al2O3(NiCoMg/Al2O3) to design MgAl2O4islands over the catalyst surface, improving catalytic performance. During steam pre-treatment, unstable aluminum leached out, migrating to the MgO so as to form MgAl2O4on the catalyst. Density functional theory calculations and data analysis show that the induced binding energy between MgAl2O4and CO2leads to the facile decomposition of CO2thus producing oxidized layers of NiCo. These layers significantly oxidize any deposited carbon and inhibit carbon diffusion into NiCo matrix for the whisker type of carbon growth, reducing carbon deposition on the catalyst. Under severe conditions (GHSV=80,000h−1at 850°C), the stream treated NiCoMg/Al2O3yielded a high conversion efficiency and high long-term stability for 3000h without any notable carbon deposition. It is worthwhile to noting that the steam pre-treatment led to stable MgAl2O4islands on the NiCoMg/Al2O3catalyst preventing carbon deposition.

The use of mild oxidants in chemical vapor deposition (CVD) reactions has proven enormously useful. This was also true for the CVD growth of carbon nanotubes. As yet though, the use of mild oxidants in the CVD of graphene has remained unexplored. Here we explore the use of CO2as a mild oxidant during the growth of graphene over Ni with CH4as the feedstock. Both our experimental and theoretical findings provide in-depth insight into the growth mechanisms and point to the mild oxidants playing multiple roles. Mild oxidants lead to the formation of a suboxide in the Ni, which suppresses the bulk diffusion of C species suggesting a surface growth mechanism. Moreover, the formation of a suboxide leads to enhanced catalytic activity at the substrate surface, which allows reduced synthesis temperatures, even as low as 700 °C. Even at these low temperatures, the quality of the graphene is exceedingly high as indicated by a negligible D mode in the Raman spectra. These findings suggest the use of mild oxidants in the CVD fabrication as a whole could have a positive impact.