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Nanoporous (NP) PdCu alloy is easily fabricated by dealloying PdCuAl ternary alloy in dilute sulfuric acid. Selectively dissolving Al from PdCuAl alloy generates the three-dimensional uniform nanosponge architecture with narrow ligament size distribution. Benefitting from the unique nanoporous architecture and the alloying effect, the as-made NP-PdCu exhibits outstanding sensing performance towards the detection of hydrogen peroxide (H 2 O 2 ) and glucose. Compared with NP-Pd and commercial Pd/C catalysts, the NP-PdCu alloy presents high sensitivity, wide linear range of 0.1-2.0mM, low detection limit of 2.1μM, and long-term stability toward H 2 O 2 detection. In addition, the NP-PdCu can efficiently detect glucose in a wide concentration range (1-30mM) with the low detection limit of 1.9μM. Moreover, the NP-PdCu exhibits good anti-interference toward ascorbic acid, uric acid, and dopamine. Characterized by easy preparation, unique electrocatalytic activity, and high structure stability, the NP-PdCu alloy possesses great application prospect to construct platform for electrochemical sensing., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Abstract: The encapsulated Au/CeO2 hollow composite shows the effects of different pretreatment conditions on CO oxidation, showing complete conversion temperatures for CO in the order O2 pretreatment (T100=74 °C)>N2 pretreatment (T100=142 °C)>CO pretreatment (T100=167 °C). Because of the good confinement provided by the uniform pores of as‐prepared CeO2, the size of deposited Au nanoparticles embedded in the pores of CeO2 can be well controlled. Pretreated Au/CeO2 catalysts have a good stability with no clear deactivation even after 70 h. A systematic characterization was performed by employing various techniques (XRD, H2 temperature‐programmed reduction, scanning transmission electron microscopy with energy‐dispersive spectroscopy, Raman spectroscopy, X‐ray photoelectron spectroscopy, and in situ diffuse reflectance infrared Fourier transform spectroscopy) to understand the importance of the Au–CeO2 interaction. This revealed that the O2 pretreatment may result in (a) the migration of lattice oxygen atoms to the surface region and clearly increased number of oxygen vacancies in CeO2; (b) the increase of Au−Ox and Au−Ox−Ce bond lengths; (c) the creation of electron holes in the CeO2 substrate and electron deficiencies in Au nanoparticles as well as a strong Au–CeO2 interaction; and (d) increased number of bicarbonates on the surface and Auδ+−CO bonds were produced during CO oxidation. All these features are responsible for an overall enhanced activity of CO oxidation and high durability of the Au/CeO2 hollow composite. [ABSTRACT FROM AUTHOR]

We descried a mild route to the straightforward fabrication of nanoporous ruthenium (NP–Ru) by one−step mild etching of RuAl alloy. NP–Ru consisted of an interconnected nanoscaled ligaments with bicontinuous hollow channels extending in all three dimensions. The resulting NP–Ru shows high catalytic activity at room temperature and a long life time toward hydrolysis of ammonia borane (AB). It is also found that NP–Ru has superior reusability as well the recyclability with 67% of their initial catalytic activity retained even after five runs. Additionally, the activation energy of the hydrolysis of AB over NP–Ru was evaluated based on the kinetic studies depending on the reaction temperature. The effect of catalyst concentration was also explored on the reaction rate of hydrolysis of AB, indicating that the hydrolysis reaction is the first–order reaction with respect to the concentration of NP–Ru. [ABSTRACT FROM AUTHOR]

Ceria nanoparticles with 4 and 7 atom-% manganese dopant were synthesized through a template-free solvothermal method. The structure of the samples was characterized by powder X-ray diffraction (XRD). Monodispersed nanospheres of average size 130 nm were observed in transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), and field-emission scanning electron microscopy (FE-SEM) analyses. Manganese ions were introduced into the system and it is confirmed that the Mn species dissolve within the CeO2 lattice by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Furthermore, the as-obtained Mn-doped ceria nanoparticles revealed superior catalytic performance in CO oxidation in contrast with pure CeO2 prepared by the same route. [ABSTRACT FROM AUTHOR]

Abstract: A one-step co-precipitation process with ethylene glycol in aqueous solution was carried out to provide a convenient and economic route for the synthesis of nanoscale LiFePO4/C composites with uniform carbon coating and excellent electrochemical performance. It can be easily scaled up for commercialization. [Copyright &y& Elsevier]

Abstract: A novel bicomponent catalyst, VO2 supported on multi-walled carbon nanotubes (MWCNTs) with defects as promoter (VO2-defects/MWCNTs) was synthesized for the hydroxylation of benzene to phenol. In the bicomponent system, VO2 nanoparticles with 2–10nm were prepared by the spontaneous redox between V5+ and defects of MWCNTs. Moreover, defects of MWCNTs were firstly used as promoters for preventing the oxidation of phenol and transferring electrons in the catalysis. Thus, compared with other vanadium catalysts, VO2-defects/MWCNTs show excellent catalytic performance for the hydroxylation of benzene to phenol, which indicates defects as promoter are quite promising for catalyzing the hydroxylation of benzene. [Copyright &y& Elsevier]