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951.
Xiao Liang Lei Shi Yipu Liu Hui Chen Rui Si Wensheng Yan Qi Zhang Guo‐Dong Li Li Yang Xiaoxin Zou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(23):7713-7717
Simultaneous realization of improved activity, enhanced stability, and reduced cost remains a desirable yet challenging goal in the search of oxygen evolution electrocatalysts in acid. Herein we report iridium‐containing strontium titanates (Ir‐STO) as active and stable, low‐iridium perovskite electrocatalysts for the oxygen evolution reaction (OER) in acid. The Ir‐STO contains 57 wt % less iridium relative to the benchmark catalyst IrO2, but it exhibits more than 10 times higher catalytic activity for OER. It is shown to be among the most efficient iridium‐based oxide electrocatalysts for OER in acid. Theoretical results reveal that the incorporation of iridium dopants in the STO matrix activates the intrinsically inert titanium sites, strengthening the surface oxygen adsorption on titanium sites and thereby giving nonprecious titanium catalytic sites that have activities close to or even better than iridium sites. 相似文献
952.
Mengmeng Lao Kun Rui Guoqiang Zhao Peixin Cui Xusheng Zheng Shi Xue Dou Wenping Sun 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(16):5486-5491
Heterostructured nanomaterials, generally have physicochemical properties that differ from those of the individual components, and thus have potential in a wide range of applications. New platinum (Pt)/nickel bicarbonate (Ni(HCO3)2) heterostructures are designed for an efficient alkaline hydrogen evolution reaction (HER). Notably, the specific and mass activity of Pt in Pt/Ni(HCO3)2 are substantially improved compared to the bare Pt nanoparticles (NPs). The Ni(HCO3)2 provides abundant water adsorption/dissociation sites and modulate the electronic structure of Pt, which determine the elementary reaction kinetics of alkaline HER. The Ni(HCO3)2 nanoplates offer a platform for the uniform dispersion of Pt NPs, ensuring the maximum exposure of active sites. The results demonstrate that, Ni(HCO3)2 is an effective catalyst promoter for alkaline HER. 相似文献
953.
Rui Feng Li Zhang Huapeng Ruan Yue Zhao Gengwen Tan Xinping Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(18):6145-6149
The first main‐group element radical based one‐dimensional magnetic chain ( 1K )n was realized by one‐electron reduction of the pyridinyl functionalized borane 1 with elemental potassium in THF in the absence of 18‐crown‐6 (18‐c‐6). The electron spin density of ( 1K )n mainly resides at the boron centers with a considerable contribution from central benzene and pyridine moieties. The spin centers exhibit an antiferromagnetic interaction as demonstrated by magnetic measurements and theoretical calculations. In contrast, the reduction in the presence of 18‐c‐6 afforded the separated radical anion salt 1K(Crown) , in which the potassium cation was trapped by THF and 18‐c‐6 molecules. Further one‐electron reduction of 1K(Crown) and ( 1K )n led to the diamagnetic monomer and polymer, respectively. 相似文献
954.
Guocan Yu Tian‐Yong Cen Zhimei He Shu‐Ping Wang Zhantong Wang Xin‐Wen Ying Shijun Li Orit Jacobson Sheng Wang Lei Wang Li‐Sen Lin Rui Tian Zijian Zhou Qianqian Ni Xiaopeng Li Xiaoyuan Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(26):8891-8895
Single molecular nanoparticles (SMNPs) integrating imaging and therapeutic capabilities exhibit unparalleled advantages in cancer theranostics, ranging from excellent biocompatibility, high stability, prolonged blood lifetime to abundant tumor accumulation. Herein, we synthesize a sophisticated porphyrin nanocage that is further functionalized with twelve polyethylene glycol arms to prepare SMNPs ( porSMNPs ). The porphyrin nanocage embedded in porSMNPs can be utilized as a theranostic platform. PET imaging allows dynamic observation of the bio‐distribution of porSMNPs , confirming their excellent circulation time and preferential accumulation at the tumor site, which is attributed to the enhanced permeability and retention effect. Moreover, the cage structure significantly promotes the photosensitizing effect of porSMNs by inhibiting the π–π stacking interactions of the photosensitizers, ablating of the tumors without relapse by taking advantage of photodynamic therapy. 相似文献
955.
Titas Braukyla Rui Xia Maryte Daskeviciene Tadas Malinauskas Alytis Gruodis Vygintas Jankauskas Zhaofu Fei Cristina Momblona Cristina Roldn‐Carmona Paul J. Dyson Vytautas Getautis Mohammad Khaja Nazeeruddin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(33):11388-11394
The synthesis of three enamine hole‐transporting materials (HTMs) based on Tröger's base scaffold are reported. These compounds are obtained in a three‐step facile synthesis from commercially available materials without the need of expensive catalysts, inert conditions or time‐consuming purification steps. The best performing material, HTM3, demonstrated 18.62 % PCE in PSCs, rivaling spiro‐OMeTAD in efficiency, and showing markedly superior long‐term stability in non‐encapsulated devices. In dopant‐free PSCs, HTM3 outperformed spiro‐OMeTAD by a factror of 1.6. The high glass‐transition temperature (Tg=176 °C) of HTM3 also suggests promising perspectives in device applications. 相似文献
956.
Fulai Liu Rui Shi Zhuan Wang Yuxiang Weng Chi‐Ming Che Yong Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(34):11917-11921
Black phosphorus (BP) has recently drawn attention in photocatalysis for its optical properties. However, limited by the rapid recombination of photogenerated carriers, the use of BP for photocatalytic water splitting still remains a huge challenge. Herein, we prepare a black/red phosphorus (BP/RP) hetero‐phase junction photocatalyst by a wet‐chemistry method to promote the interfacial charge separation and thus achieve Z‐scheme photocatalytic water splitting without using sacrificial agents. The Z‐scheme mechanism was confirmed by time‐resolved transient absorption spectroscopy. This work provides a novel insight into the interface design of hetero‐phase junction with atomic precision. 相似文献
957.
Xingjiang Wu Ri Hong Jinku Meng Rui Cheng Zhijie Zhu Guan Wu Qing Li Cai‐Feng Wang Su Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(38):13690-13698
Photonic crystals (PCs) have been widely applied in optical, energy, and biological fields owing to their periodic crystal structure. However, the major challenges are easy cracking and poor structural color, seriously hindering their practical applications. Now, hydrophobic poly(tert‐butyl acrylate) (P(t‐BA)) PCs have been developed with relatively lower glass transition temperature (Tg), large crack‐free area, excellent hydrophobic properties, and brilliant structure color. This method based on hydrophobic groups (tertiary butyl groups) provides a reference for designing new kinds of PCs via the monomers with relatively lower Tg. Moreover, the P(t‐BA) PCs film were applied as the photoluminescence (PL) enhanced film to enhance the PL intensity of CdSe@ZnS QDs by 10‐fold in a liquid‐crystal display (LCD) device. The new‐type hydrophobic force assembled PCs may open an innovative avenue toward new‐generation energy‐saving devices. 相似文献
958.
Xin‐Shen Liang Rui‐Dong Li Xiao‐Chen Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(39):14023-14027
We have developed a method for the highly diastereo‐ and enantioselective construction of 2,3‐dihydrobenzofurans bearing tetrasubstituted carbon stereocenters by means of annulation reactions between carbenes and 2‐iminyl‐ or 2‐acyl‐substituted phenols through catalysis by readily accessible copper(I)/bisoxazoline catalysts under mild conditions. These reactions feature a unique mechanism in which the copper catalyst serves a dual function: first it reacts with the diazo compound to generate a metal carbene, and second, upon formation of an oxonium ylide, it acts as a Lewis acid to activate the imine or ketone for diastereo‐ and enantioselective cyclization. 相似文献
959.
Wei Wang Rui Sun Jing Guo Jie Guo Jie Min 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(41):14698-14703
A new balanced donor–acceptor molecule, namely, benzodithiophene (BDT)‐rhodanine‐[6,6]‐phenyl‐C71 butyric acid methyl ester (Rh‐PC71BM) comprising two covalently linked blocks, a p‐type oligothiophene‐containing BDT‐based moiety and an n‐type PC71BM unit was designed and synthesized. The single‐component organic solar cell (SCOSC) fabricated from Rh‐PC71BM molecules showed a power conversion efficiency (PCE) of 3.22 % with an open‐circuit voltage (Voc) of 0.98 V. These results rank are among the highest values for SCOSCs based on a monomolecular material. In particular, the one‐molecule Rh‐PC71BM device exhibits excellent thermal stability compared to reference Rh‐OH:PC71BM device. The success of our monomolecular strategy can provide a new way to develop high‐performance SCOSCs. 相似文献
960.
Yu Duan Zi‐You Yu Shao‐Jin Hu Xu‐Sheng Zheng Chu‐Tian Zhang Hong‐He Ding Bi‐Cheng Hu Qi‐Qi Fu Zhi‐Long Yu Xiao Zheng Jun‐Fa Zhu Min‐Rui Gao Shu‐Hong Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(44):15919-15924
The anode oxygen evolution reaction (OER) is known to largely limit the efficiency of electrolyzers owing to its sluggish kinetics. While crystalline metal oxides are promising as OER catalysts, their amorphous phases also show high activities. Efforts to produce amorphous metal oxides have progressed slowly, and how an amorphous structure benefits the catalytic performances remains elusive. Now the first scalable synthesis of amorphous NiFeMo oxide (up to 515 g in one batch) is presented with homogeneous elemental distribution via a facile supersaturated co‐precipitation method. In contrast to its crystalline counterpart, amorphous NiFeMo oxide undergoes a faster surface self‐reconstruction process during OER, forming a metal oxy(hydroxide) active layer with rich oxygen vacancies, leading to superior OER activity (280 mV overpotential at 10 mA cm?2 in 0.1 m KOH). This opens up the potential of fast, facile, and scale‐up production of amorphous metal oxides for high‐performance OER catalysts. 相似文献