Fe and Au-codoping of molybdenum carbide (MoC) nanosheet for hydrogen adsorption

Abstract

Despite the natural occurrence of hydrogen in the atmosphere, complex procedures have been recorded in its extraction process, such as difficulty in compressing it, high flame speed and low ignition energy. As a result, easier and more effective strategies have been predicted using nanoparticles to adsorb hydrogen and further purification proceeds. Herein, density functional theory (DFT) has been used to study the adsorption of atomic hydrogen on the surfaces of Fe and Au-codoped molybdenum carbide (MoC) nanosheet at the PBE0-D3/Gen/6-311 + G(d,p)/LanL2DZ method. The results showed that surface engineering via metal co-doping facilitated the adsorption of atomic hydrogen. The adsorption energies were observed to be −1.1580 eV, −1.9220 eV and −5.2996 eV for H@MoC, H@FeMoC and H@AuFeMoC respectively which are relatively in the range of hydrogen adsorption as proposed by the US Department of Energy. The adsorption was greatly increased by doping with Fe and Au atoms. H@AuFeMoC reflects the greatest potential to adsorb H-atom. Highest global hardness (η) and electrophilicity (ω) values of 0.6861 eV and 8.4621 eV are attributed to H@AuFeMoC indicating that AuFeMoC surface is the most reactive and sensitive surface as compared to its studied counterparts. Finally, from the point of view of QTAIM and RDG analysis, the non-covalent nature of interactions for all studied complexes showed the excellent adsorbing attributes of the engineered MoC surfaces. Hence, the newly engineered surfaces can be used for adsorbing hydrogen atoms for future use.