Alpha-hydrogen abstraction and alpha-hydrogen migration reactions yield novel titanium(IV) complexes bearing terminal phosphinidene ligands. Via an alpha-H migration reaction, the phosphinidene ((tBu)nacnac)Ti=P[Trip](CH(2)(tBu) ((tBu)nacnac(-) = [Ar]NC((t)Bu)CHC((t)Bu)N[Ar], Ar = 2,6-(CHMe2)(2C6H3, Trip = 2,4,6-(i)Pr3C6H2) was prepared by the addition of the primary phosphide LiPH[Trip] to the nucleophilic alkylidene triflato complex ((tBu)nacnac)Ti=CH(t)Bu(OTf), while alpha-H abstraction was promoted by the addition of LiPH[Trip] to the dimethyl triflato precursor ((tBu)nacnac)Ti(CH)(2)(OTf) to afford ((tBu)nacnac)Ti=P[Trip](CH3). Treatment of ((tBu)nacnac)Ti=P[Trip](CH3) with B(C6F5)(3) induces methide abstraction concurrent with formation of the first titanium(IV) phosphinidene zwitterion complex ((tBu)nacnac)Ti=P[Trip]{CH3B(C6F5)(3)}. Complex ((tBu)nacnac)Ti=P[Trip]{CH3B(C6F5)(3)} [2 + 2] cycloadds readily PhCCPh to afford the phosphametallacyclobutene [((tBu)nacnac)Ti(P[Trip]PhCCPh)][CH3B(C6F5)(3)]. These titanium(IV) phosphinidene complexes possess the shortest Ti=P bonds reported, have linear phosphinidene groups, and reveal significantly upfielded solution 31P NMR spectroscopic resonances for the phosphinidene phosphorus. Solid state 31P NMR spectroscopic data also corroborate with all three complexes possessing considerably shielded chemical shifts for the linear and terminal phosphinidene functionality. In addition, high-level DFT studies on the phosphinidenes suggest the terminal phosphinidene linkage to be stabilized via a pseudo Ti[triple bond]P bond. Linearity about the Ti-P-C(ipso) linkage is highly dependent on the sterically encumbering substituents protecting the phosphinidene. Complex ((tBu)nacnac)Ti=P[Trip]{CH3B(C6F5))(3)} can catalyze the hydrophosphination of PhCCPh with H(2)PPh to produce the secondary vinylphosphine HP[Ph]PhC=CHPh. In addition, we demonstrate that this zwitterion is a powerful phospha-Staudinger reagent and can therefore act as a carboamination precatalyst of diphenylacetylene with aldimines.

The decomposition of carbon materials and organic binders in Li−air batteries has been reported repeatedly in recent literature. The decomposition of carbon can harm the batteries' cyclability further by catalyzing electrolyte degrading. Therefore, there is a critical need to exploit a new catalyst support substituting carbon and develop a binder free cathode preparation strategy for Li−air batteries. Herein, TiO 2 nanotube arrays growing on Ti foam are used as the catalyst support to construct carbon and binder free oxygen diffusion electrodes. After being coated with Pt nanoparticles by a cool sputtering approach, the TiO 2 nanotube arrays are used as cathodes of Li−O 2 batteries. Benefiting from the stability of TiO 2 in the discharge/charge processes, the Li−O 2 batteries realize enhanced cyclability at high current densities (for instance, more than 140 cycles at 1 or 5 A g −1 ), within wide discharge/charge voltage windows (for instance, 1.5−4.5 V). X-ray photoelectron spectra and a scanning electron microscope image of the cathodes after cycling at 5 A g −1 150 times indicate that the TiO 2 nanotubes can remain stable in the long term cycle test. 1 H nuclear magnetic resonance analysis reveals that the tetraethylene glycol dimethyl ether electrolyte has no degradation, showing enhanced stability compared with that in the carbon containing batteries.

A porous MoO 3 film is prepared by electrodeposition on Ni foam substrates and exhibits a capacity of 650 mAh g À1 at a current density of 3 A g À1 as anodes for lithium ion batteries. Electrochemical measurements demonstrate that the outstanding rate performances are due to the improved Li + diffusion kinetics.The possibility of applying rechargeable Li ion batteries (LIBs) in mobile and stationary power storage has generated numerous studies to improve their energy density, power density and cycling life. One area of active research is replacing graphite as the energy storage component in the anode with materials of higher storage capacity. Metal oxides have long been known as Li ion insertion compounds with a much higher capacity than graphite. 1 Unfortunately, bulk metal oxides generally suffer from capacity fading with cycling, especially at higher rates due to the poor kinetics. Thus, various doped metal oxide systems, nanocrystals, and nanocomposites have recently been explored to improve these properties.MoO 3 is a well-known Li + insertion compound and has been investigated during the early years of lithium battery research. 2-4 As an anode material, MoO 3 not only has a superior theoretical specific capacity of nearly 1111 mA h g À1 , 5 which is nearly three times that of graphite, 6 but also has a very stable layered structure. 7,8 This layered structure is able to act as a temporary host for intercalated Li + . 9 However, the poor kinetics of Li + diffusion in bulk layered MoO 3 limits its electrochemical performance. 10 Various forms of MoO 3 materials have been explored to improve the poor kinetics, including doped materials, 11,12 carbon coated nanobelts, 5 and nanomaterials. [13][14][15] In these modification methods, reducing the MoO 3 grain size to nanoscale is more effective for improving the performances of the MoO 3 -based anode. However, good rate performances have been demonstrated rarely in previous reports, and they are still unsatisfactory comparing with other transition metal oxides. 13,16,17 To improve the rate performances of metal oxides, constructing a porous nanostructured film is a significant strategy, 18,19 for example, synthesizing Co 3 O 4 film by a hydrothermal method, 20 preparing Co 3 O 4 film by an ammonia-evaporation-induced method, 21 depositing a hierarchical Fe 2 O 3 /Ni film using chemical vapor deposition, 22 and constructing an Fe 3 O 4 nanorod array film by electrodeposition. 23 These free-standing porous nanostructured films can facilitate Li + transmission in both the electrolyte and anode materials by their porous structure and ultra-small grain size, which improves the rate performance by enhancing the kinetics of Li + diffusion. Among the strategies for constructing free-standing porous nanostructured films, electrodeposition is a simple, controllable and low-cost method that can uniformly deposit thin films onto various metal substrates. However, reports on the preparation of a porous MoO 3 film by electrodeposition directly on the current collector are rare....

Superhydrophobic surfaces were successfully prepared on Ti/Si substrates via the fabrication of conductive polyaniline (PANI) nanowire film. The PANI nanowire film was synthesized by electrodeposition of aniline into the pores of an anodic aluminum oxide (AAO) template on Ti/Si substrate followed by the removal of the template. The surface showed conductivity and superhydrophobicity, even in many corrosive solutions, such as acidic or basic solutions over a wide pH range. Field emission scanning electron microscopy (FE-SEM) demonstrated that the binary geometric structures at micro- and nanometer scale bestowed the prerequisite roughness on the surfaces. The chemical surface modification made the PANI nanowire film superhydrophobic. The results demonstrated that the PANI nanowire film will have good potential applications in the preparation of conductive superhydrophobic surfaces.