RESUMEN
Development an alternative approach to efficiently and economically produce hydrogen from water to replace non-renewable fossil fuels is one of the great challenges in the energy field. In this paper, a Co foam (CF) with 90% porosity and pore size of a few tens of micrometers was prepared, on which FeCoP nanoflowers were in-situ formed. Such a combination was used as a new electrocatalyst/self-supporting electrode for high efficiency hydrogen evolution reaction. Thanks to the larger surface area (and thus many more active sites), and quicker mass transfer through the porous structure, the CF supported FeCoP electrode exhibited much better hydrogen evolution reaction (HER) performance than the commercial Ni foam supported counterpart prepared under identical conditions. In the case of the former, only -44 mV overpotential was required to achieve a geometric current density of -10 mA cm-2, and the electrode showed a high stability at a current density < -500 mA cm-2. The electrode developed in this work could be potentially used as a novel electrode for future large-scale production of hydrogen. In addition, the novel strategy reported here could be similarly used to develop many other types of self-supporting electrodes with further improved HER performance.
RESUMEN
ISOBAM-104-stabilized Ni2+ colloidal catalysts were synthesized through a facile method and used for hydrogen generation from hydrolysis of potassium borohydride (KBH4). Ni nanoparticles (NPs) were formed as the active phase during the catalytic process. Ultraviolet-visible spectrophotometry (UV-vis) and transmission electron microscopy were employed to characterize the structure and particle size of the as-formed Ni NPs. The results suggested that the catalytic activity of Ni2+ colloidal catalyst increased with the decreased size of as-formed Ni NPs, which is consistent with the results of density functional theory calculation. The highest catalytic activity of the catalyst can be 12400 ml-H2 min-1 g-Ni-1, which was even higher than that of noble Pt or Pd colloidal catalysts prepared using identical methods and catalytic conditions. According to the Arrhenius method, the ISOBAM-104-stabilized Ni2+ colloidal catalysts showed low activation energies of about 41.3 kJ mol-1 for the hydrogen generation from hydrolysis basic KBH4 solution.
RESUMEN
The design and controlled synthesis of two-dimensional (2D) nanomaterials have been widely studied because the properties and functions of nanomaterials are highly dependent on their sizes, shapes, and dimensionalities. For instance, 2D metal nanosheets (2DMNSs) have attracted a significant amount of attention owing to their interesting properties, which are absent in corresponding bulk counterparts, and they have been confirmed to have potential applications in electrocatalysis, optics, and biomedicine. However, because of the close-packed structures of metals, the large-scale fabrication of 2DMNSs is challenging. In this review, we have outlined the research progress in the field of 2DMNSs, including the typical synthesis approaches and newly developed methods, as well as promising applications of the materials reported in recent years. Moreover, some preliminary and promising strategies to further improve the properties of 2DMNSs and some insights for the development of the field have been included.
RESUMEN
A facile one-pot strategy was developed to prepare ultrastable monodispersed Ag nanoclusters (NCs) in aqueous solution by using ISOBAM-104, as a stabilizing agent. The as-prepared Ag NCs with an average size of 1.3 nm, which can be preserved in water solution for more than one year under ambient conditions without obvious agglomeration, exhibited excellent antibacterial activities for E. coli (DH5α), compared to most of the previously reported results.