文献类型：期刊文献

英文题名：Computational exploration of magnesium-decorated carbon nitride (g-C3N4) monolayer as advanced energy storage materials

作者：Gao, Peng[1];Li, Ji-wen[4];Zhang, Jie[2,3];Wang, Guangzhao[5]

机构：[1]Univ Wollongong, Sch Chem & Mol Biosci, Wollongong, NSW 2500, Australia;[2]East China Univ Sci & Technol, Sch Chem Engn, Shanghai 200237, Peoples R China;[3]Guangzhou Regenerat Med & Hlth Guangdong Lab, Ctr Chem & Chem Biol, Bioland Lab, Guangzhou 530000, Peoples R China;[4]Northwest Normal Univ, Coll Phys & Elect Engn, Lanzhou 730070, Peoples R China;[5]Yangtze Normal Univ, Key Lab Extraordinary Bond Engn & Adv Mat Technol, Sch Elect Informat Engn, Chongqing 408100, Peoples R China

年份：2021

卷号：46

期号：42

起止页码：21739

外文期刊名：INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

收录：;EI(收录号：20212010376177);WOS:【SCI-EXPANDED(收录号:WOS:000660300200005)】；

基金：P.G thanks Dr. Haibo Yu's supervision of Ph. D study. P.G also thanks the Australian Government, which provided him an Australian International Postgraduate Award scholarship to support his Ph. D study.

语种：英文

外文关键词：DFT; Carbon nitride; Hydrogen storage

摘要：Density functional theory (DFT) computational studies were conducted to explore the hydrogen storage performance of a monolayer material that is built on the base of carbon nitride (g-C3N4, heptazine structure) with decoration by magnesium (Mg). We found that a 2 x 2 supercell can bind with four Mg atoms. The electronic charges of Mg atoms were transferred to the g-C3N4 monolayer, and thus a partial electropositivity on each adsorbed Mg atom was formed, indicating a potential improvement in conductivity. This subse-quently causes the hydrogen molecules' polarization, so that these hydrogen molecules can be efficiently adsorbed via both van der Waals and electrostatic interactions. To note, the configurations of the adsorbed hydrogen molecules were also elucidated, and we found that most adsorbed hydrogen molecules tend to be vertical to the sheet plane. Such a phenomenon is due to the electronic potential distribution. In average, each adsorbed Mg atom can adsorb 1-9 hydrogen molecules with adsorption energies that are ranged from-0.25 eV to-0.1 eV. Moreover, we realised that the nitrogen atom can also serve as an active site for hydrogen adsorption. The hydrogen storage capacity of this Mg-decorated gC(3)N(4) is close to 7.96 wt %, which is much higher than the target value of 5.5 wt % proposed by the U.S. department of energy (DOE) in 2020 [1]. The finding in this study indicates a promising carbon-based material for energy storage, and in the future, we hope to develop more advanced materials along this direction. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.