From MAX Phase Carbides to Nitrides: Synthesis of VGaC, VGaN, and the Carbonitride VGaCN.

The research in MAX phases is mainly concentrated on the investigation of carbides rather than nitrides (currently >150 carbides and only <15 nitrides) that are predominantly synthesized by conventional solid-state techniques. This is not surprising since the preparation of nitrides and carbonitrides is more demanding due to the high stability and low diffusion rate of nitrogen-containing compounds. This leads to several drawbacks concerning potential variations in the chemical composition of the MAX phases as well as control of morphology, the two aspects that directly affect the resulting materials properties.

Magnetic and Electrocatalytic Properties of Nanoscale Cobalt Boride, CoB.

The use of low-temperature solution synthesis followed by a brief annealing step allows metastable single-phase CoB nanoparticles to be obtained, with sizes ranging from 11 to 22 nm. The particles are ferromagnetic with a saturation magnetization of 91 A m kg (corresponding to 1.02 μ/Co) and a coercive field of 0.

Synthesis of a Highly Efficient Oxygen-Evolution Electrocatalyst by Incorporation of Iron into Nanoscale Cobalt Borides.

High-performance catalysts for the oxygen-evolution reaction in water electrolysis are usually based on expensive and rare elements. Herein, mixed-metal borides are shown to be competitive with established electrocatalysts like noble metal oxides and other transition-metal(oxide)-based catalysts. Iron incorporation into nanoscale dicobalt boride results in excellent activity and stability in alkaline solutions.