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51.
《International Journal of Hydrogen Energy》2020,45(43):22833-22847
In this work, Bi2WO6/PANI composites were synthesized for efficient removal of ciprofloxacin (CIP) from urban wastewater and production of hydrogen energy in the absence of sacrificial agents. The experimental study visualizes the formation of 2D based nanostructures and perceived that these nanostructures could provide more photocatalytic active-sites for removal of CIP and also increase the oxidation/reduction of water for hydrogen energy production. The PXRD showed excellent crystallinity/orthorhombic structure with crystallite size 10–23 nm. The Bi2WO6/PANI composites, compared to Bi2WO6, exhibited higher efficiency and stability for degradation of CIP and production of hydrogen energy. CIP was effectively degraded 98% by Bi2WO6/PANI (5%) and the effect of different parameters such as pH, catalyst-concentration, and effect of CIP-concentration was also analyzed. The hydrogen energy rate was 490.56 h−1g−1 by using Bi2WO6/PANI (5%). The improved photocatalytic performance of Bi2WO6/PANI composite was mainly ascribed to the unique hierarchical structures, harvesting extended absorption of visible light, higher surface area, and higher crystallinity. The current findings may provide new insights to fabricate nanomaterials for environmental and energy issues. 相似文献
52.
《International Journal of Hydrogen Energy》2020,45(46):24573-24581
A new polyanionic organic cathode, namely sodium 2,6-dihydroxyanthraquinone (AQ26ONa), is synthesized and fully characterized for sodium-ion batteries (SIBs). Due to the two ionic Na–O bonds, the polyanionic AQ26ONa is found almost insoluble in ether-type electrolytes. Meanwhile, AQ26ONa can deliver a two-electron redox mechanism and thus a high specific capacity of 189 mAh g−1 for SIB. In half cells, the AQ26ONa electrode delivers a reversible capacity of 217 mAh g−1 for 150 cycles (50 mA g−1) and ~128 mAh g−1 for 2500 cycles (0.5 A g−1). In the full cells with the reduced state (Na4TP) of sodium terephthalate (Na2TP) as the organic anode, the resulting Na4TPIIAQ26ONa organic SIBs (OSIBs) can display an average discharge capacity of 150 mAh g−1cathode for 50 cycles and ~66 mAh g−1 for 1000 cycles during the working voltage of 0.01–3.0 V. Currently, the performance of the Na4TPIIAQ26ONa full cells is among one of the best OSIBs reported to date. 相似文献
53.
Hamed Salimkhani Tohid Joodi Aidin Bordbar-Khiabani Ali Motei Dizaji Behnam Abdolalipour Ali Azizi 《中国化学工程学报》2020,28(1):307-317
This study presents morphological and structural variations of K-Feldspar mineral after acid treatment. Both organic and inorganic acids such as C2H2O4, HCl, HNO3 and H2SO4 were employed for this purpose. Another aim of this study was to find an optimum experimental condition for iron (Fe) removal with a minimum damage on the structure of K-Feldspar in which high whiteness index is obtained. The effect of different parameters such as concentration, pH and temperature on the final structure of this mineral was investigated. To find out the chemical composition of powder, XRF was utilized. FTIR, XRD and SEM were employed to study the structure of mineral. Spectrophotometry was chosen to analyze whiteness index of powder after acid treatment. It was found that O—Al—O bond at 647 cm-1 for H2SO4 and HNO3 treated sample disappeared. However, HCl and C2H2O4 were ineffective at this band. In addition, the results revealed an increase in K-Feldspar content, a decrease in Fe content, an increase in whiteness index and no significant structural change for C2H2O4 leached sample. Whiteness index of 91% was obtained for C2H2O4 leached sample with the pH of 2.5 to 3 at temperature of 50℃ and during 1 h. 相似文献
54.
《International Journal of Hydrogen Energy》2019,44(56):29743-29751
Operational rules and control strategies of the chemically recuperated gas turbine (CRGT) in the marine propulsion are investigated in this paper. The Minimization of Gibbs free energy method is used to calculate the diesel-steam reforming reaction which products synthetic hydrogen rich fuels, and a universal model of the chemical regenerator which is easily applied to different application environments is created. The hydrogen production and hydrogen molar fraction are investigated to verify that the CRGT improve the combustion performances under low working conditions. Off-design calculations are performed to derive proper operational rules, and transient calculations are performed to investigate the best control strategies for the systems. The modelling approach of the chemical regenerator can be generally used in the chemically recuperated gas turbine. The elaborate operational rules can greatly improve the thermal efficiencies under every working condition. The system using synchronous control strategies have better regulation speed and operation stability than that using asynchronous control strategies. 相似文献
55.
《International Journal of Hydrogen Energy》2019,44(32):17238-17247
The suitability of molasses, Napier grass (Pennisetum purpureum), empty fruit bunches (EFB), palm oil mill effluent (POME), and glycerol waste as a co-substrate with Chlorella sp. TISTR 8411 biomass for biohythane production was investigated. Mono-digestion of Chlorella biomass had hydrogen and methane yield of 23–35 and 164–177 mL gVS−1, respectively. Co-digestion of Chlorella biomass with 2–6% TS of organic wastes was optimized for biohythane production with hydrogen and methane yield of 17–75 and 214–577 mL gVS−1, respectively. The hydrogen and methane yield from co-digestion of Chlorella biomass with molasses, POME, and glycerol waste was increased by 8–100% and 80–264%, respectively. The biohythane production of co-digestion of Chlorella was 6–11 L L-mixed waste−1 with an optimal C/N ratio range of 19–41 and H2/CH4 ratio range of 0.06–0.3. Co-digestion of Chlorella biomass was significantly improved biohythane production in term of yield, production rate, and kinetics. 相似文献
56.
57.
Conductive micropatterns is an essential part for operation of electronic devices in both industrial and academic fields. Conventional mask-based photolithography and vacuum deposition are inadequate to meet the demands of convenience and simplicity due to their complicated operation, costly instrumentations and relatively low resolution (for vacuum deposition). Development of simple and efficient mask-less fabrication techniques of conductive micropatterns is highly expected. Here we report a facile meniscus-confined electrochemical etching (MCEE) approach to fabricate metal micropatterns with resolution down to at least 1.0 μm. Both the applied bias and the moving velocity directly influence the patterning resolution. MCEE process is developed to fabricate source and drain electrodes in organic transistors on both rigid and flexible substrates. Being a maskless direct writing method, the width and morphology of the etched channel can be easily modulated by the bias and the velocity. The organic transistor with top-contact configuration presents better electrical performance with device on/off ratio of 1.1 × 105 and maximum carrier mobility of 1.07 cm2V−1s−1, which implies that MCEE operation doesn't result in the degradation of the already deposited semiconducting film. This mask-less MCEE approach provides a potential complementary to conventional mask-based techniques for the fabrication of microscale metal patterns. 相似文献
58.
We report on an organic-based photodetector that integrates a dual-gate organic thin-film transistor (DG-OTFT) with an organic photodiode (OPD) to produce a device with a high effective responsivity at low optical power and video-rate compatible response. In this device, the OPD operates in photovoltaic mode, instead of the commonly used photoconductive mode, to modulate one of the gate voltages of the DG-OTFT. Effective responsivity values of 10 A W−1 are measured at optical power values lower than 10 nW at 635 nm. Modeling of the operation of this new photodetector suggests that effective responsivity values up to 105 A W−1 can be achieved at optical powers of 1 nW using current printing technology and state-of-the-art organic semiconductors. 相似文献
59.
Full-fluorescence organic light-emitting diodes (FOLEDs) with low cost and high efficiency are imperious demands for commercial process in flat panel display and lighting products. We fabricated a series of FOLEDs employing C545T and DCJTB as doped dyes and different exciplex blends as cohosts. The results proved that reverse intersystem crossing (RISC) efficiency of exciplex cohost has a significant effect on the device performance. Devices with TAPC:PIM-TRZ as cohost which possessed the highest RISC efficiency showed the best results. The green FOLEDs exhibited the maximum external quantum efficiencies (EQEs) approaching to 20%, the red FOLEDs exhibited EQEs over 10% and all the EQE roll-offs are less than 10% at 1000 cd m−2, which are among the best reported results so far, suggesting these exciplex cohosts are promising for FOLEDs. 相似文献
60.
By using the π-conjugated phthalocyanine macrocycle as the versatile building block, a series of five sandwich-type ethylthio substituted phthalocyaninato europium complexes, namely double-decker Eu[Pc(SC2H5)8]2 (Pc-1), triple-decker Eu2[Pc(SC2H5)8]3 (Pc-2), and their corresponding dimers, [Pc(SC2H5)8]2Eu2[BiPc(SC2H5)12] (Pc-1@Pc-1), [Pc(SC2H5)8]3Eu3[BiPc(SC2H5)12] (Pc-1@Pc-2) and [Pc(SC2H5)8]4Eu4[BiPc(SC2H5)12] (Pc-2@Pc-2), are synthesized and prepared into the solution-processed films by a simple quasi-Langmuir-Shäfer (QLS) method. Combination between the extending π-conjugated system in the longitudinal and transverse directions of Pc macrocycles and/or radical nature of Pc-1 unit among different semiconducting molecules result in unusually small energy gaps (0.345–0.91 eV). Consequently, all of the semiconductors exhibit excellent conductivities. Among these materials, the conductivity for the radical species Pc-1@Pc-1, Pc-1@Pc-2 and Pc-1 is about 3–4 times larger than that for the non-radical compounds Pc-2@Pc-2 and Pc-2. Moreover, the QLS films of five semiconductors take excellent linear responses for both oxidizing NO2 (100–300 ppb) and reducing NH3 (4–8.6 ppm). Respectively, the sensitivity (in % ppm−1) gets increased in the order of Pc-1 < Pc-2 < Pc-1@Pc-1 < Pc-1@Pc-2 < Pc-2@Pc-2 for NO2, and Pc-1@Pc-2 < Pc-1 < Pc-1@Pc-1 < Pc-2@Pc-2 < Pc-2 for NH3. Depending on the highly extended π-conjugated systems, Pc-2@Pc-2 and Pc-2 films achieve the highest sensitivity of 208.2% ppm−1 and 0.97% ppm−1 to NO2 and NH3, respectively. In addition, with a less than 2 min response time within a limit of detection at 10 ppb for NO2 and 0.48 ppm for NH3, good reproducibility and selectivity have been revealed for the Pc-2@Pc-2 and Pc-2 films among the best gas sensors obtained so far for all the solution-processed films based on organic semiconductors in dry air at room temperature. More importantly, it is firstly demonstrated that the high NO2 sensing is resulted from low Oxd1, and high NH3 sensing is resulted from high Red1 among the sandwich Pc-based semiconductors. 相似文献