Photocatalysis holds great promise as an efficient and sustainable oxidation technology for application in wastewater treatment. Rapid progress developing novel materials has propelled photocatalysis ...to the forefront of sustainable wastewater treatments. This review presents the latest progress on applications of photocatalytic wastewater treatment. Our focus is on strategies for improving performance. Challenges and outlooks in this promising field are also discussed. We hope this review will help researchers design low-cost and high-efficiency photocatalysts for water treatment.
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Solar-driven evaporation is capable of efficiently and conveniently generating steam from water, which has been developed in the novel applications of evaporation power generation, ...steam sterilization, and fresh water extraction from seawater. It has been confirmed to be promising to reduce energy shortage and water scarcity. In this review, the design points of evaporators are summarized and integrated, and the main factors for the efficiency and long-term performance of evaporators are discussed (e.g., the selection of photothermal materials and the development of key components to achieve high-performance evaporation). Furthermore, the possibilities, opportunities, and challenges of solar-driven evaporation in energy conversion are described by exemplifying the latest research progress.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
To better understand processes involved in the evaporative drying of the soil, simulations on the dynamics of the evaporation zone, condensation zone, and dry surface layer (DSL) were conducted ...during a 10-day drying event under diurnal atmospheric conditions. Simulated water contents and soil temperatures matched well with the measured data in the lysimeter. Surface evaporation predominantly occurred during the early period each day, while subsurface evaporation dominated during the remaining part of the day. The evaporation zone presented a distinctly diurnal pattern, moving toward the deeper soil layer during the daytime and back toward the soil surface during the nighttime. The DSL and condensation zone, located immediately above and below the evaporation zone, respectively, also presented diurnal patterns following those of the evaporation zone. As soil drying progressed, both the position of the evaporation zone within the profile and the DSL width exhibited an overall increasing trend, reaching about 4.9 mm by the end of the study period. The occurrence of condensation zones was limited to the daytime when there was a downward surface temperature gradient present. Diurnal patterns observed in both evaporation zones and DSL could potentially be determined by quantifying changes in the near-surface profile’s soil water content, relative humidity, pressure head, and vapor density.
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Hydrogen generation by photocatalysis is one of the most effective approaches to rationally utilize solar energy. In this work, we designed a biphasic photothermal-photocatalytic ...system. Spherical g-C3N4 (HCN) was grown on the carbonized wood (CW) by a one-step hydrothermal method. The carbonization layer in carbonized wood/spherical g-C3N4 (CW-HCN) system was able to further enhance the photothermal conversion of water steam production by improving the absorption of solar radiation. In addition, the temperature was increased due to photothermal effect, which was beneficial for H2 evolution reaction. Moreover, the carbonized layer could act as a reservoir for photogenerated electrons on g-C3N4, which could accelerate the charge separation. Benefiting from all above-mentioned merits, the H2 evolution rate of CW-HCN system under simulated sunlight reached 2700.18 μmol/m2/h, which was 42.23 times higher than that of pristine g-C3N4 powder directly dispersed in water. In addition, the CW-HCN system exhibited broad applicability, maintaining the H2 evolution activity of 2013.29 μmol/m2/h with seawater as water resource. This work provided a new strategy for highly efficient H2 evolution.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this paper, soliton solutions of the coupled variable coefficients Schrödinger–Boussinesq equation, which describes the stationary propagation of coupled upper-hybrid waves and magnetoacoustic ...waves in a magnetized plasma, are investigated. Based on the Hirota bilinear method, the bilinear form, one, two, three and N-soliton solutions of Schrödinger–Boussinesq equation are derived. By means of numerical calculation, the specific figures of different soliton solutions are obtained by selecting different coefficients. The propagation and interaction of the soliton solutions are analyzed graphically.
•The effect of different variable coefficients on soliton solutions is investigated.•Several soliton solution results are obtained by the Hirota bilinear method.•N-soliton solutions of the equation with respect to variable coefficients are constructed.•A wealth of graphic material is provided for readers to understand.•The asymptotic behavior of two, three-soliton solutions is studied.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•A photothermal-photocatalytic system to split water vapor into H2 was fabricated.•Under AM 1.5G light irradiation, the hydrogen evolution rate of the C-wood/TiO2 system reached ...487.4 μmol·m−2·h−1.•This system can also be applied to split tap water, spring water and seawater to produce H2.•The synergetic effect and the mechanism of the enhancement have been explored and discussed.
Solar energy conversion using photocatalytic water splitting shows promising potential for resolving the current energy crisis. To split vapor into hydrogen in this study, we built a surface carbonized wood/TiO2 (C-wood/TiO2) photothermal-photocatalytic system. Natural wood that had been surface carbonized enabled stable steam production and produced a solid/gas reaction interface with a lower Gibbs free energy, enabling TiO2 to produce hydrogen photocatalytically without the need for a co-catalyst made of a noble metal. The carbonized surface was able to transfer photogenerated electrons quickly from TiO2, while also significantly enhancing solar spectrum absorption. The C-wood/TiO2 system demonstrated efficient solar spectrum utilization in vapor production and hydrogen evolution. The C-wood/TiO2 system's hydrogen evolution rate under AM 1.5G light irradiation was 487.4 μmol·m−2·h−1when using deionized water, and the cycling experiment demonstrated long-term stability. Additionally, this system could evolve hydrogen from seawater (248.1 μmol·m−2·h−1). This study showed the photothermal-photocatalytic biphasic system's strong suit and potential for producing hydrogen.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Hydrogen generation by photocatalysis is one of the most effective approaches to rationally utilize solar energy. In this work, we designed a biphasic photothermal-photocatalytic system. Spherical ...g-C
N
(HCN) was grown on the carbonized wood (CW) by a one-step hydrothermal method. The carbonization layer in carbonized wood/spherical g-C
N
(CW-HCN) system was able to further enhance the photothermal conversion of water steam production by improving the absorption of solar radiation. In addition, the temperature was increased due to photothermal effect, which was beneficial for H
evolution reaction. Moreover, the carbonized layer could act as a reservoir for photogenerated electrons on g-C
N
, which could accelerate the charge separation. Benefiting from all above-mentioned merits, the H
evolution rate of CW-HCN system under simulated sunlight reached 2700.18 μmol/m
/h, which was 42.23 times higher than that of pristine g-C
N
powder directly dispersed in water. In addition, the CW-HCN system exhibited broad applicability, maintaining the H
evolution activity of 2013.29 μmol/m
/h with seawater as water resource. This work provided a new strategy for highly efficient H
evolution.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Photoelectrochemical water splitting is an effective way to convert solar energy into hydrogen energy. In this manuscript, Pt-loaded nitrogen-deficient C3N4 was firmly grown on carbon cloth as a ...photoanode for efficiently photoelectrocatalytic (PEC) water splitting to produce hydrogen. The PEC activity of C3N4 was increased from 0 (C3N4 powder) to 2.45 mmol/h/m2. The performance was further improved to 13.49 mmol/h/m2 after the loading of Pt nanoparticles. The significant improvement in PEC performance can be summarized as the following points: (a) Carbon cloth as substrate enhanced the conductivity of C3N4 and further facilitated photogenerated charges' transfer, (b) enhanced optical absorption and emerged more active edges due to nitrogen defects and porous structures, (c) improved charge transfer and separation efficiency and increased specific surface area at nitrogen-deficient active sites, (d) Pt nanoparticles with local surface plasma resonance (LSPR) effect absorbed more optical electrons and enhanced the rate of electron transport. Therefore, Pt-NCN-CC exhibited great potentials as a photoanode for highly efficient hydrogen production.
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•A method has been developed to grow g-C3N4 on carbon clothes.•Photoelectrocatalytic activity in H2 production reached 13.49 mmol/h/m2.•The enhancement has been explored along with a proposed reaction pathway.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this study, shear tests have been performed on the as-reflowed Sn3.5Ag solder bumps and joints to investigate the deformation behavior of Sn3.5Ag lead-free solder samples. Scanning electron ...microscopy （SEM） was employed to characterize the microstructures of the samples and orientation imaging microscopy （OIM） with electron backscattered diffraction （EBSD） in SEM was used to obtain crystallographic orientation of grains to provide a detailed characterization of the deformation behavior in Sn3.5Ag solder samples after shear tests. The deformation behavior in solder samples under shear stress was discussed. The experimental results suggest that the dynamic recrystallization could occur under shear stress at room temperature and recrystallized grains should evolve from subgrains by rotation. Compared with that of non-recrystallized and as-reflowed microstructures, the microhardness of the recrystallized microstructure decreased after shear tests.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
An experimental study of thermal de-NOx using NH3 as reductant in 02/C02 atmosphere with the effect of S02 and different additives was performed in a drop tube furnace. Results show that the optimum ...temperature win- dow is 841-1184 ℃, and the optimum reaction temperature is about 900 ℃ with a de-NOx efficiency of 95.4%. A certain amount of S02 has an inhibiting effect on NO reduction. The effect of additives, including Na2C03, C2H5OH and FeCI3, on NO reduction by NH3 is also explored. The addition of Na2CO3 and FeCI3 is useful to widen the tem- perature window and shift the reaction to lower temperature for the efficiency is increased from 30.5% to 74.0% and 67.4% respectively at 800 ℃. Qualitatively, the modeling results using a detailed kinetic modeling mecha- nism represent well most of the process features. The effect of Na2CO3, C2H5OH and FeCI3 addition can be reproduced well by the Na2C03, C2H5OH and Fe（CO）5 sub-mechanism respectively. The reaction mechanism analysis shows that the effects of these additives on NO reduction are achieved mainly by promoting the produc- tion of OH radicals at lower temperature.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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