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61.
Here, a near-infrared (NIR)-absorbing small-molecule acceptor (SMA) Y-SeNF with strong intermolecular interaction and crystallinity is developed by combining selenophene-fused core with naphthalene-containing end-group, and then as a custom-tailor guest acceptor is incorporated into the binary PM6:L8-BO host system. Y-SeNF shows a 65 nm red-shifted absorption compared to L8-BO. Thanks to the strong crystallinity and intermolecular interaction of Y-SeNF, the morphology of PM6:L8-BO:Y-SeNF can be precisely regulated by introducing Y-SeNF, achieving improved charge-transporting and suppressed non-radiative energy loss. Consequently, ternary polymer solar cells (PSCs) offer an impressive device efficiency of 19.28% with both high photovoltage (0.873 V) and photocurrent (27.88 mA cm−2), which is one of the highest efficiencies in reported single-junction PSCs. Notably, ternary PSC has excellent stability under maximum-power-point tracking for even over 200 h, which is better than its parental binary devices. The study provides a novel strategy to construct NIR-absorbing SMA for efficient and stable PSCs toward practical applications.  相似文献   
62.
Underwater optical communication (UOC) has attracted considerable interest in the continuous expansion of human activities in marine/ocean environments. The water-durable and self-powered photoelectrodes that act as a battery-free light receiver in UOC are particularly crucial, as they may directly face complex underwater conditions. Emerging photoelectrochemical (PEC)-type photodetectors are appealing owing to their intrinsic aqueous operation characteristics with versatile tunability of photoresponses. Herein, a self-powered PEC photodetector employing n-type gallium nitride (GaN) nanowires as a photoelectrode, which is decorated with an iridium oxide (IrOx) layer to optimize charge transfer dynamics at the GaN/electrolyte interface, is reported. Strikingly, the constructed n-GaN/IrOx photoelectrode breaks the responsivity-bandwidth trade-off limit by simultaneously improving the response speed and responsivity, delivering an ultrafast response speed with response/recovery times of only 2 µs/4 µs while achieving a high responsivity of 110.1 mA W−1. Importantly, the device exhibits a large bandwidth with 3 dB cutoff frequency exceeding 100 kHz in UOC tests, which is one of the highest values among self-powered photodetectors employed in optical communication system.  相似文献   
63.
Rechargeable aqueous zinc batteries are promising energy storage devices because of their low cost, high safety, and high energy density. However, their performance is plagued by the unsatisfied cyclability due to the dendrite growth and hydrogen evolution reaction (HER) at the Zn anode. Herein, it is demonstrated that the concentrated hybrid aqueous/non-aqueous ZnCl2 electrolytes constitute a peculiar chemical environment for not only the Zn-ions but also water molecules. The high concentration of chloride ions substitutes the H2O molecular in the solvation structure of Zn2+, while the acetonitrile further interacts with H2O to decrease its activity. The hybrid electrolytes both inhibit the dendrite formation and HER, enabling an ultrahigh average Coulombic efficiency of 99.9% in the Zn||Cu half-cell and a highly reversible Zn plating/stripping with a low overpotential of 21 mV. Using this hybrid electrolyte, the Zn||polytriphenylamine (PTPAn) full cell deliveres a high discharge capacity of 110 mAh g−1, a high power density of 9200 W kg−1 at 100 °C and maintains 85% of the capacity for over 6000 cycles at 10 °C. This study provides a deep understanding between the solvation structure and columbic efficiency of Zn anode, thus inspiring the development for stable Zn batteries.  相似文献   
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金属-有机框架(MOF)衍生的过渡金属硒化物和多孔碳纳米复合材料具有巨大的储能优势,是应用于电化学储能的优良电极材料。采用共沉淀法制备CoFe类普鲁士蓝(CoFe-PBA)纳米立方,并通过静电组装在CoFe-PBA上包覆聚吡咯(PPy)得到CoFe-PBA@PPy;通过在400℃氮气中退火并硒化成功制备了氮掺杂的碳(NC)包覆(CoFe)Se2的(CoFe)Se2@NC纳米复合材料,并对其结构和形貌进行了表征。以(CoFe)Se2@NC为电极制备了超级电容器,测试了其电化学性能,结果表明,在电流密度1 A/g时超级电容器的比电容达到1047.9 F/g,在电流密度5 A/g下1000次循环后具有良好的循环稳定性和96.55%的比电容保持率。由于其性能优越、无毒、成本低和易于制备,未来(CoFe)Se2@NC纳米复合材料在超级电容器中具有非常大的应用潜力。  相似文献   
67.
In this paper we introduce an algebraic concept of the product of Ockham algebras called the Braided product. We show that ifL i MS(i=1, 2, ,n) then the Braided product ofL i(i=1, 2, ,n) exists if and only ifL 1, ,L n have isomorphic skeletons.  相似文献   
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银微电极微分电位溶出分析法研究   总被引:3,自引:1,他引:3  
方宾  方惠群 《分析化学》1995,23(11):1243-1246
本文首次报道了银微电极微分电位溶出分析法。用化学刻蚀法方便地制作了银微电极,用于DPSA具有背景值低,分辨率好、精密度及灵敏度高,在不搅拌,仅需一定酸度而酸度而无其它介质的条件下就能测试等优点,对人工试样及自来水样分析,结果令人满意。  相似文献   
70.
Treatment of carbonyl compounds with SmI2 and methyl chloroformate in the presence of molecular sieves provides the cyclic carbonates or biscarbonates of pinacols. This one-pot reaction proceeds rapidly even with aliphatic ketones. The stereochemistry obtained by this procedure is different from that of conventional pinacolic couplings.  相似文献   
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