Cobalt

About: Cobalt is a research topic. Over the lifetime, 69899 publications have been published within this topic receiving 1242058 citations. The topic is also known as: Co & Element 27.

Cobalt−Oxo Core of a Water-Oxidizing Catalyst Film

Abstract: In photosynthesis, water is oxidized at a protein-bound Mn4Ca complex. Artificial water-oxidation catalysts that are similarly efficient and based on inexpensive and abundant materials are of great interest. Recently, assembly of a catalyst as an amorphous layer on inert cathodes by electrodeposition starting from an aqueous solution of cobalt ions and potassium phosphate has been reported. X-ray absorption spectroscopy on the cobalt catalyst film (CoCF) suggests that its central structural unit is a cluster of interconnected complete or incomplete CoIII−oxo cubanes. Potassium ligation to Co-bridging oxygens could result in Co3K(μ-O)4 cubanes, in analogy to the Mn3Ca(μ-O)4 cubane motif proposed for the photosynthetic Mn complex. The similarities in function and oxidative self-assembly of CoCF and the catalytic Mn complex in photosynthesis are striking. Our study establishes a close analogy also with respect to the metal−oxo core of the catalyst.

Single Crystal Anisotropy and Magnetostriction Constants of Several Ferromagnetic Materials Including Alloys of NiFe, SiFe, AlFe, CoNi, and CoFe

Abstract: The anisotropy and magnetostriction of single crystals of several ferromagnetic materials have been determined experimentally. The materials include the metals iron and nickel, binary alloys of nickel iron, silicon iron, aluminum iron, cobalt nickel, and cobalt iron, ternary alloys of molybdenum nickel iron, nickel cobalt iron, and molybdenum aluminum iron, and magnetite. The effect of the order‐disorder reaction on these properties was measured for several of the alloys.The present data for the nickel iron and silicon iron systems agree well with recently published values. Ordering generally raises the magnetostriction and lowers the anisotropy of the aluminum iron alloys near the Fe3Al composition. The first anisotropy constant, K1, for the cobalt nickel system as derived from torque curves is similar to old data derived from magnetization curves. However, K1 for cobalt iron (30, 35, and 45% cobalt) appears to be considerably larger than previously reported. In general, the addition of cobalt to nickel ...