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Ti-hyperdoped Si (Site) films are formed by doping of Si with a high concentration of Ti impurities, which is three orders of magnitude above the solid solubility limit, via a non-equilibrium effect of pulsed laser. The films get id of the Si bandgap limit and have an excellent subandgap NIR ( = 1 1002 500 nm) light ab¬sorption performance. In this paper, Ti-Al co-doped Si (Si:(Ti-Al)) ilms were prepared by vacuum electron contact angle reaches 110.5°, which increases 78.0° compared with the blank substrate. The Tazel polarization curves and the detailed polarization parameters indicates that the corrosion current density of the composite coating decreases by about two orders of magnitude compared with Hank substrate and the corrosion potential positively shifts from --1.029 V to 0.989 V after the coating deposition, proving that the silicone arch resin/ Cleo 2 composite coating can significantly reduce the corrosion rate of Q235 steel and improve Us corrosion resist¬ance. To verify the influence of the different kinds of silicone monomer on the deposition of composite coatings, ethenyitrimethoxy Shane (A171) and ethoxyvinyl illume (C6Hi4OSi) as silicone monomers were investigated, respectively. The water contact angle of the coating deposited in the solution containing A171 so 30.3° larger than that of the coating deposited in the solution containing C6 Hi4 Ossie. The corrosion current density of the compote coatings increases by about two orders of magnitude after the silicone monomer changing from A171 to C6Hi4OSi, which may be caused by the longer molecular chain and the Wager spatial steric effect of C6Hi4 Ossie, making it more difficult to polymerize and depot. So A171 Is more Suita Me as silicone monomer in our re¬search system. [ABSTRACT FROM AUTHOR]

Abstracts Carbon quantum dots (CQDs) are synthesized by one pot electrochemical method using small molecule and applied as the support materials for platinum (Pt) catalysts. The effect of CQD on the catalytic activity and stability of the supported Pt catalysts for oxygen reduction reaction is investigated for the first time. The as-prepared Pt/CQD nanocomposites has been carefully characterized by spectroscopic and electrochemical techniques. X-ray diffractometer and tunneling electron microscopy techniques are employed to study the crystallite size. X-ray photoelectron spectroscopy revealed that Pt deposited to CQD. The electrochemical behavior, characterized by oxygen reduction reaction onset potentials, electrochemical active surface area, cyclic voltammetry stability (1000 cycles) and charge transfer resistance is attributed to the strong interaction between the nanosize platinum particles and the CQDs composite, which induces modulation in the electronic structure of the platinum clusters. [ABSTRACT FROM AUTHOR]

A facile synthetic route has been proposed to prepare cauliflower-like nanostructures of Cr doped Mn 2 O 3 . The synthesis was carried out by constant current cathodic electrodeposition from Mn 2+ nitrate solutions containing minor amounts of dichromate. It was found that the presence of Cr mediates the formation of cathodic MnO 2 which then reacts with the excess Mn 2+ species to form Mn 2 O 3 nanostructures. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Differential Thermal Analysis (DTA) were used to characterize the nanostructures. The storage ability of the obtained nanostructures was investigated by cyclic voltammetry (CV) in 0.5 M Na 2 SO 4 solution. The results indicated that the Cr doped manganese oxide material shows better performance than the non-doped one, and the charge capacity (SC) of doped manganese oxide (218 F/g) was higher than pure manganese oxide (208 F/g). [ABSTRACT FROM AUTHOR]

Background Microbial electrosynthesis and electro fermentation are techniques that aim to optimize microbial production of chemicals and fuels by regulating the cellular redox balance via interaction with electrodes. While the concept is known for decades major knowledge gaps remain, which make it hard to evaluate its biotechnological potential. Here we present an in silico approach to identify beneficial production processes for electro fermentation by elementary mode analysis. Since the fundamentals of electron transport between electrodes and microbes have not been fully uncovered yet, we propose different options and discuss their impact on biomass and product yields. Results For the first time 20 different valuable products were screened for their potential to show increased yields during anaerobic electrically enhanced fermentation. Surprisingly we found that an increase in product formation by electrical enhancement is not necessarily dependent on the degree of reduction of the product but rather the metabolic pathway it is derived from. We present a variety of beneficial processes with product yield increases of maximal 36% in reductive and 84% in oxidative fermentations and final theoretical product yields up to 100%. This includes compounds that are already produced at industrial scale such as succinic acid, lysine and diaminopentane as well as potential novel bio-commodities such as isoprene, para-hydroxybenzoic acid and para-aminobenzoic acid. Furthermore, it is shown that the way of electron transport has major impact on achievable biomass and product yields. The coupling of electron transport to energy conservation could be identified as crucial for most processes. Conclusions This study introduces a powerful tool to determine beneficial substrate and product combinations for electro-fermentation. It also highlights that the maximal yield achievable by bio electrochemical techniques depends strongly on the actual electron transport mechanisms. Therefore it is of great importance to reveal the involved fundamental processes to be able to optimize and advance electro fermentations beyond the level of lab-scale studies. [ABSTRACT FROM AUTHOR]

Abstract: Two new functionalized π-extended benzofuran catechol porphyrins and nanostructured Mn-porphyrins have been synthesized by a green one-pot method and structurally characterized by spectroscopic analysis. The electro-oxidation of 5,10,15,20-tetrakis(2,3-dihydroxyphenyl) porphyrins(1a-b) with four catechol units in the presence of 3-hydroxy-1H-phenalene-1-one (3) as bidentate nucleophile has been done and benzofuran rings have formed by the intermolecular and intramolecular Michel addition reactions. Coulometry and voltammetry results allowed us to propose four independent ECEC mechanisms for the electrochemical oxidation pathway. Functionalization of the porphyrins affected their photophysical properties such as the efficiency of the fluorescence that would support the energy transfer between the porphyrin core and the substituted subunits. [Copyright &y& Elsevier]