Angew Chem Int Ed Engl
November 2024
Ammonia has attracted considerable interest as a hydrogen carrier that can help decarbonize global energy networks. Key to realizing this is the development of low temperature ammonia fuel cells for the on-demand generation of electricity. However, the efficiency of such systems is significantly impaired by the sluggish ammonia oxidation reaction (AOR) and oxygen reduction reaction (ORR).
View Article and Find Full Text PDFSurface modification of heterogeneous photocatalysts with single-atom catalysts (SACs) is an attractive approach for achieving enhanced photocatalytic performance. However, there is limited knowledge of the mechanism of photocatalytic enhancement in SAC-modified photocatalysts, which makes the rational design of high-performance SAC-based photocatalysts challenging. Herein, a series of photocatalysts for the aerobic degradation of pollutants based on anatase TiO modified with various low-cost, non-noble SACs (vanadate, Cu, and Fe ions) is reported.
View Article and Find Full Text PDFIn order to solely rely on renewable and efficient energy sources, reliable energy storage and production systems are required. Hydrogen is considered an ideal solution as it can be produced electrochemically by water electrolysis and renewably while no pollutants are released when consumed. The most common catalysts in electrolyzers are composed of rare and expensive precious group metals.
View Article and Find Full Text PDFTrimetallic double hydroxide NiFeCo-OH is prepared by coprecipitation, from which three different catalysts are fabricated by different heat treatments, all at 350 °C maximum temperature. Among the prepared catalysts, the one prepared at a heating and cooling rate of 2 °C min in N atmosphere (designated NiFeCo-N -2 °C) displays the best catalytic properties after stability testing, exhibiting a high current density (9.06 mA cm at 320 mV), low Tafel slope (72.
View Article and Find Full Text PDFThe present study reports transition metal (TM = Cr, Mn and Fe) doped silicon nanotubes with tunable band structures and magnetic properties by careful selection of cluster assemblies as building blocks using the first-principles density functional theory. We found that the transition metal doping and in addition, the hydrogen termination process can stabilize the pure silicon nanoclusters or cluster assemblies and then it could be extended as magnetic nanotubes with finite magnetic moments. Study of the band structures and density of states (DOS) of different empty and TM doped nanotubes (Type 1 to Type 4) show that these nanotubes are useful as metals, semiconductors, semi-metals and half-metals.
View Article and Find Full Text PDFThe present study reports the geometry, electronic structure, growth behavior and stability of neutral and ionized nickel encapsulated germanium clusters containing 1-20 germanium atoms within the framework of a linear combination of atomic orbital density functional theory (DFT) under a spin polarized generalized gradient approximation. In the growth pattern, Ni-capped Gen and Ni-encapsulated Gen clusters appear mostly as theoretical ground state at a particular size. To explain the relative stability of the ground state clusters, variation of different parameters, such as average binding energy per atom (BE), embedding energy (EE) and fragmentation energy (FE) of the clusters, were studied together with the size of the cluster.
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