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81.
A combination of reduced graphene oxide (rGO) nanosheets grafted with regioregular poly(3‐hexylthiophene) (P3HT) (rGO‐g‐P3HT) and P3HT‐b‐polystyrene (PS) block copolymers was utilized to modify the morphology of P3HT:[6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) active layers in photovoltaic devices. Efficiencies greater than 6% were acquired after a mild thermal annealing. To this end, the assembling of P3HT homopolymers and P3HT‐b‐PS block copolymers onto rGO‐g‐P3HT nanosheets was investigated, showing that the copolymers were assembled from the P3HT side onto the rGO‐g‐P3HT nanosheets. Assembling of P3HT‐b‐PS block copolymers onto the rGO‐g‐P3HT nanosheets developed the net hole and electron highways for charge transport, thereby in addition to photoluminescence quenching the charge mobility (μh and μe) values increased considerably. The best charge mobilities were acquired for the P3HT50000:PC71BM:rGO‐g‐P3HT50000:P3HT7000‐b‐PS1000 system (μh = 1.9 × 10?5 cm2 V–1 s–1 and μe = 0.8 × 10?4 cm2 V–1 s–1). Thermal annealing conducted at 120 °C also further increased the hole and electron mobilities to 9.8 × 10?4 and 2.7 × 10?3 cm2 V–1 s–1, respectively. The thermal annealing acted as a driving force for better assembly of the P3HT‐b‐PS copolymers onto the rGO‐g‐P3HT nanosheets. This phenomenon improved the short circuit current density, fill factor, open circuit voltage and power conversion efficiency parameters from 11.13 mA cm?2, 0.63 V, 62% and 4.35% to 12.98 mA cm?2, 0.69 V, 68% and 6.09%, respectively. © 2019 Society of Chemical Industry 相似文献
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Mehdi Shafiee Ardestani Alireza Salehi Fordoei Asghar Abdoli Reza Ahangari Cohan Golnaz Bahramali Seyed Mehdi Sadat Seyed Davar Siadat Hamid Moloudian Nasser Nassiri Koopaei Azam Bolhasani Pooneh Rahimi Soheila Hekmat Mehdi Davari Mohammad Reza Aghasadeghi 《Journal of materials science. Materials in medicine》2015,26(5):1-8
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Shi Yuyuan Taylor Lindsey Waterton Cheung Vien Sayem Abu Sadat Muhammad 《Applied Composite Materials》2022,29(1):159-171
Applied Composite Materials - Current sports bras are typically manufactured via a cut and sew process resulting in a high volume of post-production material waste. Seams derived from this cut and... 相似文献
86.
Iranian Polymer Journal - Atom transfer radical polymerization (ATRP) of n-butyl methacrylate (n-BMA) was performed using CuIBr/N,N,N′,N″,N″-pentamethyldiethylenetriamine (PMDETA)... 相似文献
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88.
Kalantary Samira Akbari Torkestani Javad Shahidinejad Ali 《The Journal of supercomputing》2021,77(12):13806-13827
The Journal of Supercomputing - Due to high and unpredictable connection delays, privacy gaps, and traffic load of networks connecting cloud computing to end users in many of the Internet of Things... 相似文献
89.
Poly(vinyl alcohol) (PVA) hydrogel membranes were prepared through three different preparation methods including freeze-thawing (FT), solution casting (SC) followed by thermal annealing, and phase separation (PS). The prepared hydrogels were characterized by Fourier transform-infrared spectroscopy, X-ray diffractometry, and scanning electron microscopy. Nitrofurazone (NFZ) was then loaded in the hydrogels. FT and SC methods led to obtaining dense membranes, while PS method resulted in an asymmetric one. The effects of hydrogel preparation method on water absorption, gel fraction, water vapor and oxygen permeabilities, bacterial barrier, tensile properties, and drug release profiles were investigated. The water vapor permeability of the hydrogel prepared through PS method was about 1.5 times higher than those obtained through FT and SC methods. Gel formation in PS method is probably responsible for the highest degree of crystallinity, and consequently the maximum gel fraction for the corresponded membrane. The elongation-at-break for this membrane in wet state was 41% higher than that made by FT method and 18% greater than that of SC method. Membranes prepared by all three methods showed excellent barrier property against bacterial penetration during 1 week. The results showed that PS membrane could control the release of NFZ more effectively as compared with the other two samples. 相似文献
90.
Zhou Daojin Cai Zhao Bi Yongmin Tian Weiliang Luo Ma Zhang Qian Zhang Qian Xie Qixian Wang Jindi Li Yaping Kuang Yun Duan Xue Bajdich Michal Siahrostami Samira Sun Xiaoming 《Nano Research》2020,13(1):292-292
Nano Research - The labels in Fig. 8 in the original version of this article were unfortunately misplaced. The corrected figure is as follow. 相似文献