First-principles study on the electronic structure of a LiFePO4 (010) surface adsorbed with carbon

The electronic structures of a LiFePO4 (010) surface adsorbed with C are studied by a first-principles method based on DFT. The results show that the system is more stable when the LiFePO4 (010) surface is cut through Li atoms. PDOS analysis shows that the electronic structure of atoms in the sub-surface is similar to that of atoms in the bulk. The unpaired electrons in Fe-d orbital play a key role in the changes in the microelectronic structure; these changes lower the band gap and generate new bands that favor the transfer of electrons. Atom C reacts with Fe by chemisorptions when C is adsorbed on the outermost layer. Therefore, the materials may have better electrochemical properties by the improvement of diffusion of both electrons and Li ions when limiting the crystal growth with C coating. (C) 2012 Elsevier B.V. All rights reserved.