International Conference on Materials Science and Research
November 16-18, 2017 Dubai, UAE
Adsorption and Gas-Sensing Characteristics of a Stoichiometric A-Fe2O3 (0 0 1) Nano Thin Film for Carbon Dioxide and Carbon Monoxide with and without Pre-Adsorbed O2
Changmin Shi1*, YanpingChen2, HongmeiLiu1, GuangliangCui1, Lin Ju3 and Li Chen1
1Instituteof Condensed Matter Physics, Linyi University, China
2School of Physics, Shandong University, China
3School of Physics and Electric Engineering, Anyang Normal University, China
The adsorption and gas-sensing characteristics of CO2 and CO molecules on stoichiometric α-Fe2O3 (0 0 1) nano-thin film with and without pre-adsorbed O2 molecules had beenstudied using the density functional theory (DFT) method. Without preadsorbed O2 molecules, CO2 molecule played as an acceptor and obtains electrons from stoichiometricα-Fe2O3 (0 0 1) nano-thin film. For the O2 pre-adsorptionα-Fe2O3 (0 0 1) nano-thin film system, the CO2 molecule alsoplayedas an acceptor. However, less number of electrons was transferred to CO2 molecule ascompared to pre-adsorbed O2 molecule. Different from CO2 molecule, CO molecule always played as a donor forα-Fe2O3 (0 0 1) nano-thin film system with and without pre-adsorbed O2. The theoretical results verify that the CO molecule can react with lattice or adsorbed oxygen of α-Fe2O3 (0 0 1) nano-thin film. The electrons transferred to the stoichiometric α-Fe2O3 (0 0 1) nano-thin film from CO molecule/new formed CO2 molecule were more than that of transferred to the O2 pre-adsorption α-Fe2O3 (0 0 1) nano-thin film. For stoichiometric or O2 pre-adsorption α-Fe2O3 (0 0 1) nano-thin film, the CO2and CO moleculesexhibited opposite behaviors ofcharge transformation. In addition, pre-adsorbed O2 molecules displayed competitive adsorption with CO2 or CO molecule. The pre-adsorbed O2 molecules hinder electron transfer to CO2 molecule fromαFe2O3 (0 0 1) nano-thin film or hinder electron transfer toα-Fe2O3 (0 0 1) nano-thin film from CO molecule. Theoretical results demonstrate that the (0 0 1) surface of α-Fe2O3materials could be prepared as adsorbents or gas sensors for CO2 and CO molecules. Their structures were stable after CO2 molecules were adsorbed or after the reaction of CO molecules withlattice or adsorbed oxygen ofα-Fe2O3 (0 0 1) nano-thin film.
Changmin Shi was born in May 26, 1986. He received his B.S. degree in Condensed Matter Physics (2010-2015) from Shandong University. At present,he worked as a teacher in Institute of Condensed Matter Physics, School of Physics and Electric Engineering, Linyi University.