Alkali (Li, K and Na) and alkali-earth (Be, Ca and Mg) Adatoms on SiC single layer

•Alkali and alkali-earth atoms are adsorbed on the top of a Si atom in a single SiC layer.•The adsorbed atoms give rise to new electronic levels inside the band gap.•The adsorption of a H2 molecule on the doped system is ruled by dispersive forces.•The calculated adsorption spectra shows that the doped SiC layer present photocalytic properties.•The calculated free energy diagrams show that the doped system present interesting properties for HER and OER.