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排序方式: 共有280条查询结果,搜索用时 296 毫秒
271.
Wenhao Bai Mingming Liang Dr. Tongtong Xuan Ting Gong Prof. Liang Bian Prof. Huili Li Prof. Rong-Jun Xie 《Angewandte Chemie (International ed. in English)》2023,62(50):e202312728
With increasing ecological and environmental concerns, tin (Sn)-based perovskite light-emitting diodes (PeLEDs) are competitive candidates for future displays because of their environmental friendliness, excellent photoelectric properties, and low-cost solution-processed fabrication. Nonetheless, their electroluminescence (EL) performance still lags behind that of lead (Pb)-based PeLEDs due to the fast crystallization rate of Sn-based perovskite films and undesired oxidation from Sn2+ to Sn4+, leading to poor film morphology and coverage, as well as high density defects. Here, we propose a ligand engineering strategy to construct high-quality phenethylammonium tin iodide (PEA2SnI4) perovskite films by using L-glutathione reduced (GSH) as surface ligands toward efficient pure red PEA2SnI4-based PeLEDs. We show that the hydrogen-bond and coordinate interactions between GSH and PEA2SnI4 effectively reduce the crystallization rate of the perovskites and suppress the oxidation of Sn2+ and formation of defects. The improved pure red perovskite films not only show excellent uniformity, density, and coverage but also exhibit enhanced optical properties and stability. Finally, state-of-the-art pure red PeLEDs achieve a record external quantum efficiency of 9.32 % in the field of PEA2SnI4-based devices. This work demonstrates that ligand engineering represents a feasible route to enhance the EL performance of Sn-based PeLEDs. 相似文献
272.
Chiral amino thioacetate ligands were prepared from the corresponding amino alcohols and used as catalysts for enantioselective aryl transfer reaction. The amino thioacetates were remarkably superior to the corresponding amino alcohols. Low catalyst loadings of only 1-2.5 mol % were sufficient to achieve excellent enantioselectivity as well as high conversion in short reaction time. The results reveal that the thioacetoxy moiety of the amino thioacetates has a surprisingly beneficial effect in enhancing the asymmetric induction. 相似文献
273.
Prasanna Sivasubramani Tae Joo Park Brian E. Coss Antonio Lucero Jie Huang Barry Brennan Yu Cao Debdeep Jena Huili Xing Robert M. Wallace Jiyoung Kim 《固体物理学:研究快报》2012,6(1):22-24
We have investigated the effect of trimethyl aluminum (TMA) and water (H2O) half‐cycle treatments on HF‐treated, and O3‐oxidized GaN surfaces at 300 °C. The in‐situ X‐ray photoelectron spectroscopy results indicate no significant re‐growth of Ga–O–N or self‐cleaning on HF‐treated and O3‐oxidized GaN substrates with exposure to water and TMA. This result is different from the self‐cleaning effect of Ga2O3 seen on sulfur‐treated GaAs or InGaAs substrates. O3 causes aggressive oxidation of GaN substrate and direct O–N bonding compared to H2O. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
274.
Zhu G Wang X Li H Pan L Sun H Liu X Lv T Sun Z 《Chemical communications (Cambridge, England)》2012,48(7):958-960
Y(3)Al(5)O(12):Ce phosphors have been prepared and used as an effective scattering layer on top of a transparent layer of nanocrystalline TiO(2) for dye sensitized solar cells (DSSCs). The Y(3)Al(5)O(12):Ce scattering layer increases the photocurrent of DSSCs due to the enhanced light harvesting mainly via the improved light absorption and scattering. Under one sun illumination (AM 1.5G, 100 mW cm(-2)), a high efficiency of 7.91% was achieved for the cell with a Y(3)Al(5)O(12):Ce scattering layer, which is an increase of 13.5% compared to the cell without a scattering layer (6.97%). 相似文献
275.
Huili Liu 《Journal of Geometry》1999,64(1-2):141-149
We give the classification of the translation surfaces with constant mean curvature or constant Gauss curvature in 3-dimensional Euclidean space E3 and 3-dimensional Minkowski space E
1
3
.The author is supported by the EDU. COMM. of CHINA, the NSF of Liaoning and the Northeastern University.Dedicated to Professor Udo Simon on the occation of his sixtieth birthday 相似文献
276.
Regenerated cellulose membranes have been traditionally manufactured using the viscose or the copper‐ammonia process. Today, membranes made by this process are still used in many fields such as dialysis. However, there are some serious environmental problems inherent in the existing processing routes. The new N‐methylmorpholine‐N‐oxide (NMMO) process can overcome these disadvantages and provides membranes with improved mechanical properties. In the present work, cellulose membranes were successfully prepared from NMMO solution under various conditions. It was found that the cellulose concentration is a decisive factor in controlling the membrane permeation properties. For a given coagulation system, higher cellulose concentration leads to membranes with greater rejection of bovine serum albumin (BSA) and lower pure water flux. It was also found that both the degree of polymerization (DP) and the type of cellulose pulp have great effect on the morphology and permeation properties of the membrane support layer. With increasing NMMO concentration and temperature of the coagulation bath, the pure water flux increases while the rejection of BSA decreases; a result of the larger mean pore size formed during coagulation. 相似文献
277.
278.
Organic Excitonic State Management by Surface Metallic Coupling of Inorganic Lanthanide Nanocrystals
Wenxing Zhang Shan Wang Wenpeng Ye Yiyuan Zhu Cheng-Ao Li He Wang Chaomin Dong Dr. Huili Ma Prof. Mi Yan Prof. Zhongfu An Prof. Wei Huang Prof. Renren Deng 《Angewandte Chemie (International ed. in English)》2023,62(52):e202312151
The ability to harness charges and spins for control of organic excitonic states is critical in developing high-performance organic luminophores and optoelectronic devices. Here we report a facile strategy to efficiently manipulate the electronic energy states of various organic phosphors by coupling them with inorganic lanthanide nanocrystals. We show that the metallic atoms exposed on the nanocrystal surface can introduce strong coupling effects to 9-(4-ethoxy-6-phenyl-1,3,5-triazin-2-yl)-9H-carbazole (OCzT) and some organic chromophores with carbazole functional groups when the organics are approaching the nanocrystals. This unconventional organic–inorganic hybridization enables a nearly 100 % conversion of the singlet excitation to fast charge transfer luminescence that does not exist in pristine organics, which broadens the utility of organic phosphors in hybrid systems. 相似文献
279.
280.
Dr. Dongdong Wang Huili Peng Shaojie Zhang Hongxia Liu Nana Wang Prof. Jian Yang 《Angewandte Chemie (International ed. in English)》2023,62(50):e202315834
Aqueous zinc metal batteries hold great promise for large-scale energy storage because of their high safety, rich material resources and low cost. However, the freeze of aqueous electrolytes hinders low-temperature operation of the batteries. Here, aqueous localized anion-cation aggregated electrolytes composed of Zn(BF4)2 as the salt and tetrahydrofuran (THF) as the diluent, are developed to improve the low-temperature performance of the Zn anode. THF promotes the inclusion of BF4− in the solvation sheath of Zn2+, facilitating the formation of ZnF2-rich solid-electrolyte-interphase. THF also affects the hydrogen bonding between neighboring H2O molecules, effectively lowering the freezing point. Therefore, the full cells of Zn||polyaniline (PANI) exhibit an ultralong cycle life of 8000 cycles with an average Coulombic efficiency of 99.99 % at −40 °C. Impressively, the pouch cells display a high capacity retention of 86.2 % after 500 cycles at −40 °C, which demonstrates the great prospect of such electrolytes in cold regions. This work provides new insights for the design of low-temperature aqueous electrolytes. 相似文献