Peidong Yang

Bio: Peidong Yang is an academic researcher from University of California, Berkeley. The author has contributed to research in topics: Nanowire & Perovskite (structure). The author has an hindex of 183, co-authored 562 publications receiving 144351 citations. Previous affiliations of Peidong Yang include Max Planck Society & University of California, Santa Barbara.

Catalytic Growth of Zinc Oxide Nanowires by Vapor Transport

Abstract: nanoparticles in dimethylsulfoxide onto the PLL film for about 20 min, after which it was rinsed in dimethylsulfoxide and then dichloromethane. From the molecular weight, the average length of the PLL is about 30 nm. Therefore, each polymer can accommodate about seven or eight nanoparticles. [20] L. Clarke, M. N. Wybourne, M. Yan, S. X. Cai, J. F. W. Keana, Appl. Phys. Lett. 1997, 71, 617. [21] A. A. Middleton, N. S. Wingreen, Phys. Rev. Lett. 1993, 71, 3198. [22] G. Y. Hu, R. F. O'Connell, Phys. Rev. B 1994, 49, 16 773. [23] A. J. Rimberg, T. R. Ho, J. Clarke, Phys. Rev. Lett. 1995, 74, 4714. [24] L. Clarke, M. N. Wybourne, M. Yan, S. X. Cai, L. O. Brown, J. Hutchison, J. F. W. Keana, J. Vac. Sci. Technol. B 1997, 15, 2925. [25] The capacitance matrix was calculated for different chain lengths using the software package FastCap MIT (1992). We used the nanoparticle dimensions given in the text and a ligand shell dielectric constant of 3. For nanoclusters away from the end of the chains we obtain Cdd » 0.04 aF and Cg » 0.17 aF. As expected, the value of Cg is slightly larger than the value calculated for an isolated metal sphere of radius a coated with a dielectric shell, Cg» (4pee0a)/(1 + (a/d)(e±1)) = 0.14 aF, where d is the total radius of the core plus ligand shell. [26] Simulations were carried out using both MOSES (Monte-Carlo SingleElectronics Simulator, R. H. Chen) and SIMON (Simulation of Nano Structures, C. Wasshuber). [27] S. Chen, R. S. Ingram, M. J. Hostetler, J. J. Pietron, R. W. Murray, T. G. Schaaff, J. T. Khoury, M. M. Alvarez, R. L. Whetton, Science 1998, 280, 2098. [28] L. Y. Gorelik, A. Isacsson, M. V. Voinova, B. Kasemo, R. I. Shekhter, M. Jonson, Phys. Rev. Lett. 1998, 80, 4526. [29] O. D. Häberlen, S. C. Chung, M. Stener, N. Rösch, J. Chem. Phys. 1997, 106, 5189. [30] Y. Awakuni, J. H. Calderwood, J. Phys. D: Appl. Phys. 1972, 5, 1038. [31] G. Markovich, C. P. Collier, J. R. Heath, Phys. Rev. Lett. 1998, 80, 3807. [32] C. P. Collier, R. J. Saykally, J. J. Shiang, S. E. Hendrichs, J. R. Heath, Science 1997, 277, 1978. [33] N. Mott, Metal Insulator Transitions, Taylor and Francis, London 1990.

Generalized syntheses of large-pore mesoporous metal oxides with semicrystalline frameworks

Abstract: Surfactants have been shown to organize silica into a variety of mesoporous forms, through the mediation of electrostatic, hydrogen-bonding, covalent and van der Waals interactions1,2,3,4,5,6,7,8. This approach to mesostructured materials has been extended, with sporadic success, to non-silica oxides5,6,7,8,9,10,11,12,13,14,15,16,17, which might promise applications involving electron transfer or magnetic interactions. Here we report a simple and versatile procedure for the synthesis of thermally stable, ordered, large-pore (up to 140 A) mesoporous metal oxides, including TiO2, ZrO2, Al2O3, Nb2O5, Ta2O5, WO3, HfO2, SnO2, and mixed oxides SiAlO3.5, SiTiO4, ZrTiO4, Al2TiO5 and ZrW2O8. We used amphiphilic poly(alkylene oxide) block copolymers as structure-directing agents in non-aqueous solutions for organizing the network-forming metal-oxide species, for which inorganic salts serve as precursors. Whereas the pore walls of surfactant-templated mesoporous silica1 are amorphous, our mesoporous oxides contain nanocrystalline domains within relatively thick amorphous walls. We believe that these materials are formed through a mechanism that combines block copolymer self-assembly with complexation of the inorganic species.

Highly Crystalline Multimetallic Nanoframes with Three-Dimensional Electrocatalytic Surfaces

Abstract: Control of structure at the atomic level can precisely and effectively tune catalytic properties of materials, enabling enhancement in both activity and durability. We synthesized a highly active and durable class of electrocatalysts by exploiting the structural evolution of platinum-nickel (Pt-Ni) bimetallic nanocrystals. The starting material, crystalline PtNi3 polyhedra, transforms in solution by interior erosion into Pt3Ni nanoframes with surfaces that offer three-dimensional molecular accessibility. The edges of the Pt-rich PtNi3 polyhedra are maintained in the final Pt3Ni nanoframes. Both the interior and exterior catalytic surfaces of this open-framework structure are composed of the nanosegregated Pt-skin structure, which exhibits enhanced oxygen reduction reaction (ORR) activity. The Pt3Ni nanoframe catalysts achieved a factor of 36 enhancement in mass activity and a factor of 22 enhancement in specific activity, respectively, for this reaction (relative to state-of-the-art platinum-carbon catalysts) during prolonged exposure to reaction conditions.

Nanowire ultraviolet photodetectors and optical switches

Abstract: no attention has been given to the photoconducting properties of nanowires despite the exciting possibilities for use in optoelectronic circuits. Here, we show the possibility of creating highly sensitive nanowire switches by exploring the photoconducting properties of individual semiconductor nanowires. The conductivity of the ZnO nanowires is extremely sensitive to ultraviolet light exposure. The light-induced conductivity increase allows us to reversibly switch the nanowires between “OFF” and “ON” states, an optical gating phenomenon analogous to the commonly used electrical gating. [2,3,10]

Shape Control of Colloidal Metal Nanocrystals

Abstract: Colloidal metal nanoparticles are emerging as key materials for catalysis, plasmonics, sensing, and spectroscopy. Within these applications, control of nanoparticle shape lends increasing functionality and selectivity. Shape-controlled nanocrystals possess well-defined surfaces and morphologies because their nucleation and growth are controlled at the atomic level. An overall picture of shaped metal particles is presented, with a particular focus on solution-based syntheses for the noble metals. General strategies for synthetic control are discussed, emphasizing key factors that result in anisotropic, nonspherical growth such as crystallographically selective adsorbates and seeding processes.

Fast parallel algorithms for short-range molecular dynamics

Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Electronics and optoelectronics of two-dimensional transition metal dichalcogenides.

Abstract: Single-layer metal dichalcogenides are two-dimensional semiconductors that present strong potential for electronic and sensing applications complementary to that of graphene.

A comprehensive review of zno materials and devices

Abstract: The semiconductor ZnO has gained substantial interest in the research community in part because of its large exciton binding energy (60meV) which could lead to lasing action based on exciton recombination even above room temperature. Even though research focusing on ZnO goes back many decades, the renewed interest is fueled by availability of high-quality substrates and reports of p-type conduction and ferromagnetic behavior when doped with transitions metals, both of which remain controversial. It is this renewed interest in ZnO which forms the basis of this review. As mentioned already, ZnO is not new to the semiconductor field, with studies of its lattice parameter dating back to 1935 by Bunn [Proc. Phys. Soc. London 47, 836 (1935)], studies of its vibrational properties with Raman scattering in 1966 by Damen et al. [Phys. Rev. 142, 570 (1966)], detailed optical studies in 1954 by Mollwo [Z. Angew. Phys. 6, 257 (1954)], and its growth by chemical-vapor transport in 1970 by Galli and Coker [Appl. Phys. ...