[MAT-22]Local functionalization of a digital microfluidic device with an antimicrobial polydopamine coating

The hydrophobic surface on the top plate of digital microfluidic device was locally modified via the polydopamine film. There are four critial variables that directly affect the roughness, thickness and size of polydopamine film including concentration of dopamine solution, incubation time, deposition method and the volume of dopamine solution. High concentration and two-step incubation contributes to a higher roughness of polydopamine film quantified with 3D Surface Metrology.

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[MAT-21]A low-potential, low molecular weight boron-based anolyte for nonaqueous redox flow batteries

The development of non-aqueous redox flow batteries (NARFBs) were believed as the potential device for sustainable energy storage due to its wide electrochemical windows ( >5V), marching to high energy density ( >50Wh/L). Herein, we report the first examples of using boron ß-diketonates as anolyte in NARFBs. The di-tert-butyl derivative tBuBF2 exhibited superior redox reversibility at -1.83V with high solubility of 2.0M in acetonitrile. Coupling with the catholyte DBMMB, the RFBs demonstrated an exceptionally high cell voltage of 2.57V over 100 cycles with high theoretical energy density of 69 Wh/L, verifying tBuBF2 is a promising electroactive anolyte for NARFBs.

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[MAT-20]Quantifying electron transfer kinetics on porous carbon electrodes for redox flow batteries

Despite the critical role of electron transfer kinetics in determining the energy efficiency and the power density of a redox flow battery (RFB), there has not been much progress quantifying the kinetics on commercial porous carbon electrodes, the most common RFB electrodes with no immediate planar-electrode counterparts for cyclic voltammetry (CV) analyses. Here, we tackle this challenge by encapsulating porous carbon electrodes in epoxy, whose cross-sections are used for CV analyses. These electrodes display behaviors of micro-electrodes with length scales characteristic of fibers in the original porous structures. We thereby characterize the kinetics of ferricyanide reduction and corroborate these findings with symmetric RFB tests. The method developed here provides a much-needed assessment of kinetics on porous carbon electrodes free from the impacts of mass transports in the pores, enabling the identification of performance-determining factors of RFB electrodes.

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[MAT-19]High capacity electrolytes for redox flow batteries

In this poster we show our work on learning the factor that influence the anthraquinone derivatives’ solubility. We found that cation’s hydration energy and lattice energy have the major influence. Based on these results we made the solubility correlation between sulfate and sulfonate salts. With this correlation, we successfully prepared the high solubility vanadium-2,7-anthraquinone hybrid electrolyte. Battery test showed that the hybrid electrolyte can achieve high capacity and good cycling performance.

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[INORG-25]DFT studies on copper-catalyzed dearomatization of pyridine

A systematic theoretical study has been performed with the aid of density functional theory (DFT) calculations on the mechanism of asymmetric 1,4-dearomatization of free pyridine with styrene and dimethoxy(methyl)silane (HSiMe(OMe)2) catalyzed by copper complexes. Two proposed mechanisms, dearomatization of pyridine catalyzed by cooperation of two copper(I) centers and by one copper(I) are calculated and analyzed. The calculation results indicate that one copper(I) center is capable of catalyzing the dearomatization reaction. The origin of selectivity between 1,2- and 1,4-dearomatization of pyridine and the substituent effect have also been systematically discussed.

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[INORG-24]Solvothermal synthesis of metal imidazolate frameworks with 2-D honeycomb structure

Two-dimensional honeycomb structure frameworks were solvothermal synthesized by benzene halide and aniline with the ratio of metal: ligand: base=1:4:2. The SXRD determines to [Cd(BzIm)2]n·0.25n(solvent) (solvent= chlorobenzene I, fluorobenzene II, and aniline III) were selected to introduced. They are centrosymmetric orthorhombic space group Pbcn with high thermal stability. The solvent sits inside the layers and could be removed without framework collapse.

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[INORG-23]The synthesis of rhenium (VII) bis-vinyl complexes by nucleophilic addition of phosphines to alkynes

The organometallic reactions of alkyne have been studied for decades, including previously reported synthesis of rhenium carbyne and η2-vinyl complexes from reactions of alkynes with rhenium hydride complexes.1 We have recently studied the reactions of the rhenium (III) acetonitrile complex ReCl3(MeCN)(PPh3)2 with a series of aromatic alkynes (H−C≡C−R, e.g. R = phenyl, 2-trifluoromethyl-benzenyl, 3-ethynyl-benzenyl, 4-ethynyl-benzenyl, 4-biphenyl, 4-carbazole-benzenyl). The reactions were found to give rhenium (VII) bis-η2-vinyl complexes 2, as a result of intermolecular nucleophilic attack of triphenylphosphine on the coordinated alkyne. In this presentation, the detailed findings arising from the investigation will be described.

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[INORG-22]1,4-selective hydrovinylation of diene catalyzed by iron diimine catalyst: a computational case study on two-state reactivity

Our DFT study on an example of iron catalyzed 1,4-hydrovinylation of a 1,3-diene with an unactivated olefin reported by Chirik, Schmidt, and coworkers reveals a “two-state reactivity” phenomenon. Using our recently developed Principal Interacting Spin Orbital (PISO) analysis, we found that the two-state reactivity phenomenon could be understood as the interplay between orbital interaction, exchange interaction, and coordination geometry. The singlet state favors the orbital interaction between metal center and substrates, whereas the triplet state structure has higher flexibility that it can isomerize more easily.

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