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High-performance battery-type electrodes based on TiO 2 nanotube arrays decorated with Co 0·12 Ni 1·88 S 2 @Co 8 S 9 (CNCS) nanoparticles have been successfully prepared in this paper. The highly conductive TiO 2 nanotube arrays modified with carbon and oxygen vacancies (Ti 3+ defects) ( m -TNAs) are selected as the three-dimensional backbones to support electroactive materials and offer direct pathways for electron and ions transport. Then CNCS nanoparticles are electrodeposited on each nanotube uniformly, and the loading mass of nanoparticles can be controlled through adjusting electrodeposition cycles. After optimization, a remarkable specific capacity of 680.1 C g −1 is achieved at 2 A g −1 as a result of the intrinsic synergetic contributions from structural/compositional/componental merits. This specific capacity is much higher than most of the TNAs-based energy storage electrodes. In addition, an asymmetric supercapacitor device is assembled by applying the optimized CNCS/m-TNAs and commercial active carbon as positive and negative electrode, respectively. It displays a high energy density of 45.5 Wh kg −1 at a power density of 400.5 W kg −1 , after cycling for 3000 cycles at a high current density of 4 A g −1 , the specific capacitance could still remain 85.7%. This self-supported and binder-free CNCS/m-TNAs electrode will be a competitive and promising candidate for the application in energy storage. [ABSTRACT FROM AUTHOR]

Abstract: Breast tumors contain a small population of tumor initiating stem-like cells, termed breast cancer stem cells (BCSCs). These cells, which are refractory to chemotherapy and radiotherapy, are thought to persist following treatment and drive tumor recurrence. We examined whether BCSCs are similarly resistant to hyperthermic therapy, and whether nanoparticles could be used to overcome this resistance. Using a model of triple-negative breast cancer stem cells, we show that BCSCs are markedly resistant to traditional hyperthermia and become enriched in the surviving cell population following treatment. In contrast, BCSCs are sensitive to nanotube-mediated thermal treatment and lose their long-term proliferative capacity after nanotube-mediated thermal therapy. Moreover, use of this therapy in vivo promotes complete tumor regression and long-term survival of mice bearing cancer stem cell-driven breast tumors. Mechanistically, nanotube thermal therapy promotes rapid membrane permeabilization and necrosis of BCSCs. These data suggest that nanotube-mediated thermal treatment can simultaneously eliminate both the differentiated cells that constitute the bulk of a tumor and the BCSCs that drive tumor growth and recurrence. [Copyright &y& Elsevier]

Abstract: Graphene-supported Pt and Pt3M (M=Co and Cr) alloy nanoparticles are prepared by ethylene glycol reduction method and characterized with X-ray diffraction and transmission electron microscopy. X-ray diffraction depicted the face-centered cubic structure of Pt in the prepared materials. Electron microscopic images show the high dispersion of metallic nanoparticles on graphene sheets. Electrocatalytic activity and stability of the materials is investigated by rotating-disk electrode voltammetry. Oxygen reduction activity of the Pt3M/graphene is found to be 3–4 times higher than that of Pt/graphene. In addition, Pt3M/graphene electrodes exhibited overpotential 45–70mV lower than that of Pt/graphene. The high catalytic performance of Pt3M alloys is ascribed to the inhibition of formation of (hydr) oxy species on Pt surface by the alloying elements. The fuel cell performance of the catalysts is tested at 353K and 1atm. Maximum power densities of 790, 875, and 985mW/cm2 are observed with graphene-supported Pt, Pt3Co, and Pt3Cr cathodes, respectively. The enhanced electrocatalytic performance of the Pt3M/graphene (M=Co and Cr) compared to that of Pt/graphene makes them a viable alternative to the extant cathodes for energy conversion device applications. [Copyright &y& Elsevier]

Abstract: Nanoparticles of various transition elements such as palladium, iron, and nickel were synthesized in situ in the polydimethylsiloxane (PDMS) matrix by thermal decomposition of their corresponding acetylacetonate salts. Various complementary techniques such as XRD, TEM and XPS were used to characterize the nanoparticles formed in the polymer matrix. This synthesis route results in relatively monodisperse nanoparticles with a narrow particle size distribution. In addition, the composite films are pore-free and mechanically stable, making them attractive for a range of applications. Palladium-PDMS membranes can be used as catalytic membrane reactors and show enhanced catalytic activity in ethylene hydrogenation. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) is a vital process in numerous energy conversion systems, and therefore, considerable attention has been devoted to the fabrication of nonnoble and highly efficient electrode materials for OER. Herein, Co nanoparticles embedded in the N, P-codoped porous carbon (Co/P-N-C) are synthesized using a novel Co-based metal-organic polymer (Co-MOP) as the precursor through carbonization and a subsequent phosphorization treatment process. When the phosphorization treatment is carried out at pH 3, Co/P-N-C exhibits a very low overpotential of 300 mV for a current density of 10 mA cm−2 with a small Tafel slope of 61 mV dec−1 and excellent stability over 20000 s. The electrocatalytic performance of Co/P-N-C was even better than that of the commercial RuO 2 material. Density functional theory calculations were used to simulate the electrocatalytic process and to verify the experimental findings, which showed that the superior OER performance was attributed to the active sites of doped P and Co nanoparticles. This viable strategy of using a novel Co-MOP to create a novel phosphorized Co/P-N-C microporous carbon-based material may expand the opportunities for the exploration of high-performance and robust nonnoble metal electrocatalysts for energy-conversion reactions. Co atoms on N, P co-doped porous carbon via phosphorization on Co-MOP exhibit excellent OER performance due to the synergistic effects of P and Co. Image 1 • A phosphorization strategy to prepare a porous MOP-derived Co-P-N-C nanosphere. • The as-obtained yolk-shell Co-P-N-C nanosphere possesses the high electrocatalytic activity for OER. • Reveal the P and Co synergistic mechanism for forming more active sites of Co-P-N-C. [ABSTRACT FROM AUTHOR]

• A high yield of C 2+ products achieved in CuO/ZnO/C tandem catalysts. • Phase-separated geometric arrangement facilitated CO transport. • Optimal composition balanced CO generation and dimerization rate. • CO utilization efficiency as the key to increase the C 2+ products yield discussed. The comprehensive application of electrochemical CO 2 conversion to multi-carbon hydrocarbons and oxygenates is limited by the low selectivity and activity of copper-derived catalysts. Here, we report co-precipitated CuO/ZnO/C catalysts directing cascade catalysis to enhance the yield of the C 2+ products. The reduced ZnO nanoparticles supply extra CO to increase the *CO surface coverage on the reduced CuO nanoparticles, which boosts the C C coupling reaction kinetics on the reduced CuO surface. The geometric arrangement and composition of phase-separated CuO and ZnO nanoparticles are two vital factors influencing the CO utilization efficiency. The optimum CuO/ZnO/C catalyst exhibits a maximum Faradic efficiency of 74.0 % for overall C 2+ products and 50.9 % for C 2 H 4 at -0.75 V vs. reversible hydrogen electrode, at which the total current density reaches 367 mA cm−2. [ABSTRACT FROM AUTHOR]