The electronic structure and diffusion energy barriers of Li ions in pure and Mn-doped LiFePO4 have been studied using density functional theory(DFT).The results demonstrate clearly that Fe-O covalent bond is weaker t...The electronic structure and diffusion energy barriers of Li ions in pure and Mn-doped LiFePO4 have been studied using density functional theory(DFT).The results demonstrate clearly that Fe-O covalent bond is weaker than P-O covalent bond.Pure LiFePO4 has band gap of 0.56 eV and diffusion energy barrier of 2.57 eV for Li ions,while the dopant has small band gap of 0.25 eV and low diffusion energy barrier of 2.31 eV,which indicates that the electronic and ionic conductivity of LiFePO4 have been improved owing to doping.展开更多
The adsorption and decomposition of N2O on the InN （0001） surface have been explored employing density functional theory method. To study the most favorable N2O adsorption model, ten typical adsorption cases （four ...The adsorption and decomposition of N2O on the InN （0001） surface have been explored employing density functional theory method. To study the most favorable N2O adsorption model, ten typical adsorption cases （four for the parallel style and six for the vertical style） were proposed. The calculated results indicate that the parallel models are energetically preferred over the vertical models. The parallelly adsorbed N2O prefers to be dissociated on the surface, the dissociated O atom is combined at the fcc site, and the N-N piece is desorbed from the surface and forms N2 molecules. The comparison of the density of states of InN （0001） surface before and after N2O adsorption is analyzed in detail. Through the searching for transition state of decomposition reaction, a very low energy barrier of 45.0 KJ/mol is derived.展开更多
文摘The electronic structure and diffusion energy barriers of Li ions in pure and Mn-doped LiFePO4 have been studied using density functional theory(DFT).The results demonstrate clearly that Fe-O covalent bond is weaker than P-O covalent bond.Pure LiFePO4 has band gap of 0.56 eV and diffusion energy barrier of 2.57 eV for Li ions,while the dopant has small band gap of 0.25 eV and low diffusion energy barrier of 2.31 eV,which indicates that the electronic and ionic conductivity of LiFePO4 have been improved owing to doping.
基金Supported by the National Natural Science Foundation of China (No. 21073034)the State Key Laboratory of Structural Chemistry (No. 20090060)
文摘The adsorption and decomposition of N2O on the InN （0001） surface have been explored employing density functional theory method. To study the most favorable N2O adsorption model, ten typical adsorption cases （four for the parallel style and six for the vertical style） were proposed. The calculated results indicate that the parallel models are energetically preferred over the vertical models. The parallelly adsorbed N2O prefers to be dissociated on the surface, the dissociated O atom is combined at the fcc site, and the N-N piece is desorbed from the surface and forms N2 molecules. The comparison of the density of states of InN （0001） surface before and after N2O adsorption is analyzed in detail. Through the searching for transition state of decomposition reaction, a very low energy barrier of 45.0 KJ/mol is derived.
