1. Graphene- and Phosphorene-like Boron Layers with Contrasting Activities in Highly Active Mo2B4 for Hydrogen Evolution
- Author
-
Boniface P. T. Fokwa, Jan P. Scheifers, Andrew Encinas, Yuemei Zhang, Hyounmyung Park, and Palani R. Jothi
- Subjects
Inorganic chemistry ,chemistry.chemical_element ,02 engineering and technology ,Crystal structure ,010402 general chemistry ,Electrochemistry ,01 natural sciences ,Biochemistry ,Catalysis ,law.invention ,chemistry.chemical_compound ,symbols.namesake ,Colloid and Surface Chemistry ,law ,Hydrogen evolution ,Boron ,Chemistry ,Graphene ,General Chemistry ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Gibbs free energy ,Phosphorene ,Chemical physics ,symbols ,0210 nano-technology ,Layer (electronics) - Abstract
Two different boron layers, flat (graphene-like) and puckered (phosphorene-like), found in the crystal structure of Mo2B4 show drastically different activities for hydrogen evolution, according to Gibbs free energy calculations of H-adsorption on Mo2B4. The graphene-like B layer is highly active, whereas the phosphorene-like B layer performs very poorly for hydrogen evolution. A new Sn-flux synthesis permits the rapid single-phase synthesis of Mo2B4, and electrochemical analyses show that it is one of the best hydrogen evolution reaction active bulk materials with good long-term cycle stability under acidic conditions. Mo2B4 compensates its smaller density of active sites if compared with highly active bulk MoB2 (which contains only the more active graphene-like boron layers) by a 5-times increase of its surface area.
- Published
- 2017
- Full Text
- View/download PDF