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《Mendeleev Communications》2021,31(6):800-803
New random ternary copolymers containing fragments of pyrrolo[3,4-c]pyrrole-1,4-dione, 2,3-bis[6-fluoro-9-(2-octyl- dodecyl)-9H-carbazol-3-yl]-3,3′-[5,7-di(thiophen-2-yl)- thieno[3,4-b]pyrazine as electron-withdrawing fragments and benzodithiophene as an electron-donor block have been synthesized. The best power conversion efficiency of 9.18% was achieved for the terpolymer with pyrrolopyrroledione/ thienopyrazine ratio of 1:3. The introduction of the third thieno[3,4-b]pyrazine acceptor block into the structure of the ‘parent’ binary polymer can significantly adjust energy levels and the light absorption range of irregular copolymers, and can enhance photovoltaic properties due to improved absorption capacity and charge transfer.  相似文献   
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A simple, cost-effective strategy was developed to effectively improve the electron transfer efficiency as well as the power output of microbial fuel cells (MFCs) by decorating the commercial carbon paper (CP) anode with an advanced Mo2C/reduced graphene oxide (Mo2C/RGO) composite. Benefiting from the synergistic effects of the superior electrocatalytic activity of Mo2C, the high surface area, and prominent conductivity of RGO, the MFC equipped with this Mo2C/RGO composite yielded a remarkable output power density of 1747±37.6 mW m−2, which was considerably higher than that of CP-MFC (926.8±6.3 mW m−2). Importantly, the composite also facilitated the formation of 3D hybrid biofilm and could effectively improve the bacteria–electrode interaction. These features resulted in an enhanced coulombic efficiency up 13.2 %, nearly one order of magnitude higher than that of the CP (1.2 %).  相似文献   
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A novel methodology was implemented in the present study to concurrently control power conversion efficiency (η) and durability (D) of co-sensitized dye solar cells. Applying response surface methodology (RSM) and Desirability Function (DF), the main influential assembling (dye volume ratio and anti-aggregation agent concentration) and operational (performance temperature) parameters were systematically changed to probe their main and interactive effects on the η and D responses. Individual optimization based on RSM elucidated that D can be solely controlled by changing the ratio of vat-based organic photosensitizers, whereas η takes both effects of dye volume ratio and anti-aggregation concentration into account. Among the studied factors, the performance temperature played the most vital role in η and D regulation. In particular, however, multi-objective optimization by DF explored the degree to which one should be careful about manipulation of assembling and operational parameters in the way maximization of performance of a co-sensitized dye solar cell.  相似文献   
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A novel one-step protocol for the preparation of porous polyurea material (PPU) through precipitation polymerization of toluene diisocynate (TDI) is presented. The process is based on step polymerization of one singlemonomer, TDI, with water in water-acetonemixed solvent. PPU is obtained without need for any porogen or additives, and no any chemical modification on the outcome polymer is necessary. The morphology, pore size and size distribution of PPU are characterized by scanning electron microscope and BET nitrogen adsorption. Taking acid fuchsine (AF) and Congo Red as dye examples in wastewaters, their adsorption on, desorption from PPU and the reusability of PPU were tested. Experimental conditions for AF adsorption were optimized with regard to pH, adsorption time, AF concentration and amount of PPU. Results demonstrate that the as-prepared PPU is of high performance in dyes adsorption and recycled use. This work presents therefore a novel and attractive candidate for removal of anionic dyes from wastewaters.  相似文献   
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Four main chain polymeric metal complexes (P1–P4) based on 1,10‐phenanthroline metal complexes via the Heck coupling have been synthesized and characterized by Fourier transform infrared spectroscopy, 1H NMR, UV–Vis absorption, photoluminescence spectroscopy, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetry, elemental analysis, and cyclic voltammetry. To investigate their photovoltaic properties, the dye‐sensitized solar cells based on these polymers dyes are studied, under the illumination of AM 1.5G, 100 mW/cm2. The study results show the four polymers exhibit good thermally stable and the solar cells based on them have good device performance, and the maximum power conversion efficiency is up to 0.735% for the solar cells based on P3 with a short‐circuit current (Jsc) of 1.68 mA/cm2 and an open‐circuit voltage (Voc) of 0.62 V. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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ABSTRACT

Methods have been found for sintering titania nanoparticles at low temperature, e.g., <150°C, and for rapid sensitization of the sintered particles. This discovery means that dye-sensitized, titania solar cells can be made on flexible substrates, such as poly(ethylene terephthalate), in a continuous roll-to-roll manufacturing process. The ability to produce solar cells in a continuous fashion should substantially lower the cost of the cells compared to batch processed, on-glass cells. The combined attributes of spectral sensitivity, flexibility, light weight, impact resistance and low cost should find utility a variety of handheld appliances in both indoor and outdoor situations. In its most advanced state of development, this technology would find application in off-grid power generation and thus provide the opportunity of bringing solar generated electricity to rural areas of the world.  相似文献   
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