Germanium nanowires (GeNWs) with p- and n-dopants were synthesized by chemical vapor deposition (CVD) and were used to construct complementary field-effect transistors (FETs). Electrical transport and X-ray photoelectron spectroscopy (XPS) data are correlated to glean the effects of Ge surface chemistry to the electrical characteristics of GeNWs. Large hysteresis due to water molecules strongly bound to GeO(2) on GeNWs is revealed. Different oxidation behavior and hysteresis characteristics and opposite band bending due to Fermi level pinning by interface states between Ge and surface oxides are observed for p- and n-type GeNWs. Vacuum annealing above 400 degrees C is used to remove surface oxides and eliminate hysteresis in GeNW FETs. High-kappa dielectric HfO(2) films grown on clean GeNW surfaces by atomic layer deposition (ALD) using an alkylamide precursor is effective in serving as the first layer of surface passivation. Lastly, the depletion length along the radial direction of nanowires is evaluated. The result suggests that surface effects could be dominant over the "bulk" properties of small diameter wires.

A novel process for NO and SO simultaneous removal using a vacuum ultraviolet (VUV, with 185 nm wavelength)-activated O/HO/HO system in a wet VUV-spraying reactor was developed. The influence of different process variables on NO and SO removal was evaluated. Active species (O and ·OH) and liquid products (SO, NO, SO, and NO) were analyzed. The chemistry and routes of NO and SO removal were investigated. The oxidation removal system exhibits excellent simultaneous removal capacity for NO and SO, and a maximum removal of 96.8% for NO and complete SO removal were obtained under optimized conditions. SO reaches 100% removal efficiency under most of test conditions. NO removal is obviously affected by several process variables. Increasing VUV power, HO concentration, solution pH, liquid-to-gas ratio, and O concentration greatly enhances NO removal. Increasing NO and SO concentration obviously reduces NO removal. Temperature has a dual impact on NO removal, which has an optimal temperature of 318 K. Sulfuric acid and nitric acid are the main removal products of NO and SO. NO removals by oxidation of O, O·, and ·OH are the primary routes. NO removals by HO oxidation and VUV photolysis are the complementary routes. A potential scaled-up removal process was also proposed initially.

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Developing highly active electrocatalysts with low cost and high efficiency for oxygen evolution reactions (OER) is important for the practical implementations of hydrogen energy. Here, we report a Zn-doped CoSe nanosheets grown on free-standing carbon fabric collector (CFC), which was synthesized by using a metal-organic framework (MOF) as precursor and followed by a selenylation process. Importantly, the Zn-doped CoSe/CFC electrode exhibited an obviously enhanced catalytic activity for OER in 1 M KOH aqueous solution compared with CoSe/CFC, showing a small overpotential of 356 mV for a current density of 10 mA cm, a small Tafel slope of 88 mV dec, and an excellent stability. The robust and free-standing electrode shows great potential as an economic catalyst for OER applications.

Au–Pd nanoalloy in hydrophilic mesoporous poly(ionic liquid) shows high activity for oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid with atmospheric O2.

The oxidation removal of nitric oxide (NO) from flue gas using UV photolysis of aqueous hypochlorite (Ca(ClO) and NaClO) in a photochemical spraying reactor was studied. The key parameters (e.g., light intensity, hypochlorite concentration, solution temperature, solution pH, and concentration of NO, SO, O, and CO), mechanism and kinetics of NO oxidation removal were investigated. The results demonstrate that UV and hypochlorite have a significant synergistic role for promoting the production of hydroxyl radicals (·OH) and enhancing NO removal. NO removal was enhanced with the increase of light intensity, hypochlorite concentration, or O concentration but was inhibited with the increase of NO or CO concentration. Solution temperature, solution pH, and SO concentration have double the effect on NO removal. NO is oxidized by ·OH and hypochlorite, and ·OH plays a key role in NO oxidation removal. The rate equation and kinetic parameters of NO oxidation removal were also obtained, which can provide an important theoretical basis for studying the numerical simulation of NO absorption process and the amplification design of the reactor.

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