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Copper-Catalyzed Intermolecular Heck-Like Coupling of Cyclobutanone Oximes Initiated by Selective C-C Bond Cleavage

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Copper-Catalyzed Intermolecular Heck-Like Coupling of Cyclob...

中国化学会第十二届全国物理有机化学学术会议

作者： Binlin Zhao Zhuangzhi Shi State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing University

*** Cyclobutanones and their derivatives are very useful ***-metal catalysts,mainly rhodium,palladium and nickelcomplexes,have been successfully used for the activation of C-C bonds in these *** have reported the first case on intermolecular Hecklike reaction of cyclobutanone derivatives with olefins in which nitrile

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GaN-on-Si blue/white LEDs:epitaxy,chip,and package

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Journal of Semiconductors 2016年第4期37卷 61-68页

作者：孙钱严威冯美鑫李增成封波赵汉民杨辉 Key Laboratory of Nanodevices and Applications Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China LatticePower(Changzhou)Corporation Changzhou 213164China LatticePower(Jiangxi)Corporation Nanchang 330029China University of Chinese Academy of Sciences Beijing 100049China

The dream of epitaxially integrating III-nitride semiconductors on large diameter silicon is being fulfilled through the joint R＆D efforts of academia and industry, which is driven by the great potential of Ga N-onsilicon technology in improving the efficiency yet at a much reduced manufacturing cost for solid state lighting and power electronics. It is very challenging to grow high quality Ga N on Si substrates because of the huge mismatch in the coefficient of thermal expansion（CTE） and the large mismatch in lattice constant between Ga N and silicon, often causing a micro-crack network and a high density of threading dislocations（TDs） in the Ga N ***-composition graded Al Ga N/Al N buffer layers have been utilized to not only build up a compressive strain during the high temperature growth for compensating the tensile stress generated during the cool down, but also filter out the TDs to achieve crack-free high-quality n-Ga N film on Si substrates, with an X-ray rocking curve linewidth below 300 arcsec for both（0002） and（10N12） diffractions. Upon the Ga N-on-Si templates, prior to the deposition of p-Al Ga N and p-Ga N layers, high quality In Ga N/Ga N multiple quantum wells（MQWs） are overgrown with well-engineered V-defects intentionally incorporated to shield the TDs as non-radiative recombination centers and to enhance the hole injection into the MQWs through the via-like structures. The as-grown Ga N-on-Si LED wafers are processed into vertical structure thin film LED chips with a reflective p-electrode and the N-face surface roughened after the removal of the epitaxial Si（111） substrates, to enhance the light extraction efficiency. We have commercialized Ga N-on-Si LEDs with an average efficacy of 150–160 lm/W for 1mm^2 LED chips at an injection current of 350 m A, which have passed the 10000-h LM80 reliability test. The as-produced Ga N-on-Si LEDs featured with a single-side uniform emission and a nearly Lambertian distribution can adopt the wafer-level p

关键词： III-nitride semiconductors LED GaN-on-Si

Rh(Ⅰ)-Catalyzed Tertiary Phosphine Directed C-H Arylation:Rapid Construction of Ligand Libraries by A Facile In Situ Modification

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Rh(Ⅰ)-Catalyzed Tertiary Phosphine Directed C-H Arylation:R...

中国化学会第十二届全国物理有机化学学术会议

作者： Xiaodong Qiu Zhuangzhi Shi State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing University

*** Traditional routes to build the aryl substituted phosphine ligands need at least three steps(Figure 1a,1b). Our stratagy is P atom directed C-H arylation,this late-stage modification process will greatly improve t...

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具有优异光电化学性能的三维p-CuO/n-ZnO异质结光阴极材料（英文）

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Science China Materials 2016年第10期59卷 825-832页

作者：武芳丽曹风人刘琼卢豪李亮 College of Physics Optoelectronics and EnergyJiangsu Key Laboratory of Thin FilmsCenter for Energy Conversion Materials&Physics(CECMP)Soochow UniversitySuzhou 215006China

为提高光电化学分解水的效率,本文设计并制作了一种具有独特纳米结构与组分的光电极材料.首先利用水浴和原子层沉积(ALD)相结合的方法合成出以氧化铜纳米圆锥结构作为支架,氧化锌纳米棒作为树枝状的三维纳米结构,并进一步用这种结构作... 详细信息

为提高光电化学分解水的效率,本文设计并制作了一种具有独特纳米结构与组分的光电极材料.首先利用水浴和原子层沉积(ALD)相结合的方法合成出以氧化铜纳米圆锥结构作为支架,氧化锌纳米棒作为树枝状的三维纳米结构,并进一步用这种结构作为光电极进行光解水.通过实验测试,在所有三维纳米结构中,生长参数为37个循环的原子层沉积氧化锌种子层、水浴反应时间为55分钟的三维p型氧化铜/n型氧化锌(p-CuO/n-ZnO)异质结光阴极材料具有最好的光解水性能.其光暗电流密度之比达到了6.4,远远高于比值为2.7的纯氧化铜电极.三维p-CuO/n-ZnO异质结材料所表现出的优异光解水性能归功于氧化铜和氧化锌形成的异质结,该异质结有效地促进了载流子的收集和分离、降低了载流子的复合几率、延长了载流子的寿命.本文也同时证明了利用原子层沉积技术设计并制作新型三维纳米结构光电极材料的可行性.

关键词： CuO photoelectrochemical cells photocathodes atomic layer deposition heterojunction

Strong optical nonlinearities of self-assembled polymorphic microstructures of phenylethynyl functionalized fluorenones

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Chinese Chemical Letters 2018年第2期29卷 297-300页

作者： Xinyue Li Sergey Semin Leandro A. Estrada Chunqing Yuan Yulong Duan Jonathan Cremers Paul Tinnemans Paul Kouwer Alan E. Rowan Theo Rasing Jialiang Xu School of Chemical and Engineering Technology Tianjin University Tianjin 300350 China Institute for Molecules and Materials (IMM) Radboud University 6525 A J Nijrnegen The Netherlands Center for Photochemical Sciences Bowling Green State University Bowling Green OH 43403 USA Solvay Specialty Polymers Alpharetta CA 30005 USA Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland Brisbane OLD 4072 Australia

Highly efficient nonlinear optical（NLO） materials with well-defined architectures in the wavelength and subwavelength length scales are of particular importance for next generation of integrated photonic circuits. Fluorenone analogues have been demonstrated to be promising candidates as building blocks for assembly of organic NLO materials thanks to their synergistic supramolecular interactions and brilliant optical properties. Here we have studied the polymorphs of a phenylethynyl functionalized fluorenone derivative, and their controlled self-assembly for microstructures with different morphologies. These polymorphic microcrystals exhibit very distinctive NLO properties, highly related to their supramolecular and electronic structures.

关键词： Nonlinear optics Second harmonic generation Two-photon excited fluorescence Transition dipole Fluorenone

Regioselective C-H Arylation of Indoles at Benzene Core

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Regioselective C-H Arylation of Indoles at Benzene Core

中国化学会第十二届全国物理有机化学学术会议

作者： Youqing Yang Pan Gao Zhuangzhi Shi State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing University

＜正＞*** In the past decade,direct C-H arylation of indoles has been developed with high selectivity at the C2 and C3 positions via transition-metal-catalyzed crosscoupling ***,we reported a series of work that C-H activation can be directed to the C4-C7 positions with high regioselectivity in transition-metal-catalyzed coupling of indoles with different aryl groups.1,2,3Some of these works used the same indoles as the substrate.（Scheme 1）.

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Nickel-Catalyzed Retro-Hydroamidocarbonylation of Aliphatic Amides to Olefins

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Nickel-Catalyzed Retro-Hydroamidocarbonylation of Aliphatic ...

中国化学会第十二届全国物理有机化学学术会议

作者： Jiefeng Hu Zhuangzhi Shi State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Chemistry for Life SciencesSchool of Chemistry and Chemical EngineeringNanjing University

＜正＞*** Amide and olefins are important synthetic intermediates with complementary reactivity which play a key role in the construction of natural products,pharmaceuticals and manmade *** the normally highly stable aliphatic amides into olefins directly is a challenging *** we show that a Ni/NHC-catalytic system has been established for decarbonylative elimination of aliphatic amides to generate various olefins via C-N and C-C bond ***

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铂修饰二氧化钛纳米片的制备及其光电催化析氢反应研究（英文）

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无机材料学报 2019年第11期34卷 1200-1204页

作者：苏琨张亚茹陆飞张君王熙内蒙古大学化学化工学院呼和浩特010021 包头医学院药学院包头014040 北京交通大学理学院北京100044

利用静电吸附作用在二氧化钛纳米片上负载铂原子制备了两种不同形态的铂催化剂。SEM、XRD、TEM测试结果表明,改变铂负载量可以调控铂的形貌结构。在低Pt负载(0.2wt%)下,铂原子主要是半径约2 nm的纳米簇,当Pt负载量增加到1wt%时,铂原子... 详细信息

利用静电吸附作用在二氧化钛纳米片上负载铂原子制备了两种不同形态的铂催化剂。SEM、XRD、TEM测试结果表明,改变铂负载量可以调控铂的形貌结构。在低Pt负载(0.2wt%)下,铂原子主要是半径约2 nm的纳米簇,当Pt负载量增加到1wt%时,铂原子在二氧化钛纳米片上堆积成纳米颗粒。调控Pt负载量和纳米结构,可以显著提高二氧化钛纳米片催化析氢反应的活性。在AM1.5太阳光照射下,两种催化剂的塔菲尔斜率都小于100mV/dec,分别为56和90 mV/dec。与TiO2-Pt1%催化剂相比, TiO2-Pt0.2%具有更理想的金属-半导体界面,有利于光生电子迁移至铂纳米簇表面,因而具有更高的催化活性。本实验为研究更加高效的铂催化剂和其他光电催化剂提供了新的途径。

关键词：析氢反应铂纳米簇二氧化钛光电催化

Origin of the anomalous trends in band alignment of GaX/ZnGeX_2(X = N, P, As, Sb) heterojunctions

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Journal of Semiconductors 2019年第4期40卷 17-21页

作者： Ruyue Cao Hui-Xiong Deng Jun-Wei Luo Su-Huai Wei State Key Laboratory of Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences University of Chinese Academy of Sciences Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Beijing Computational Science Research Center

Utilizing first-principles band structure method, we studied the trends of electronic structures and band offsets of the common-anion heterojunctions GaX/ZnGeX_2(X = N, P, As, Sb). Here, ZnGeX_2 can be derived by atomic transmutation of two Ga atoms in GaX into one Zn atom and one Ge atom. The calculated results show that the valence band maximums(VBMs) of GaX are always lower in energy than that of ZnGeX_2, and the band offset decreases when the anion atomic number increases. The conduction band minimums(CBMs) of ZnGeX_2 are lower than that of GaX for X = P, As, and Sb, as expected. However, surprisingly, for ZnGeN2, its CBM is higher than GaN. We found that the coupling between anion p and cation d states plays a decisive role in determining the position of the valence band maximum, and the increased electronegativity of Ge relative to Ga explains the lower CBMs of ZnGeX_2 for X = P, As, and Sb. Meanwhile, due to the high ionicity, the strong coulomb interaction is the origin of the anomalous behavior for nitrides.

关键词： GaX/ZnGeX2 heterojunctions band offsets atomic orbital coupling