RESUMO
The search for efficient and low-cost electrocatalysts for the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) is of utmost importance for the production of hydrogen and oxygen via water splitting. In this work, the catalytic performance of the OER and HER on transition metal doped boron nanotubes (BNTs) was investigated using density functional theory. It was found that the doped transition metal atoms determine the catalytic activity of the BNTs. Rhodium-doped BNTs exhibited excellent OER activity, while cobalt-doped BNTs displayed great catalytic activity toward the HER. Volcano relationships were found between the catalytic activity and the adsorption strength of reaction intermediates. Rhodium- and cobalt-doped BNTs exhibited great OER and HER catalytic activity due to the favorable adsorption strength of reaction intermediates. This work sheds light on the design of novel electrocatalysts for water splitting and provides helpful guidelines for the future development of advanced electrocatalysts.
RESUMO
Polypyridyl transition metal complexes are well-established homogeneous electrocatalysts for the reduction of CO2. In this work, the relationship between the transition metal (including V, Cr, Mn, Nb, Mo, Ta, W, and Re) and the catalytic activity has been theoretically investigated using density functional theory. It is found that the transition metal center determines the catalytic activity of M(bpy)(CO)4. Among the eight metal complexes, Re(bpy)(CO)4 and Mn(bpy)(CO)4 exhibit better catalytic activity due to the weaker adsorption strength of CO and lower d-band center, which makes it easier to activate the metal complex and results in a lower reaction free energy of the rate-determining step at the reduction potential. We believe that these results can provide guidelines for the design of novel electrocatalysts for CO2 reduction.
