title: Tuning hydrogen storage in lithium-functionalized BC2N sheets by doping with boron and carbon.
abstract: First-principles calculations are used to explore the strong binding of lithium to boron- and carbon-doped BC2N monolayers (BC2NBC and BC2NCN, respectively) without the formation of lithium clusters. In comparison to BC2N and BC2NCB, lithium-decorated BC2NBC and BC2NCN systems possess stronger s-p and p-p hybridization and, hence, the binding energy is higher. Lithium becomes partially positively charged by donating electron density to the more electronegative atoms of the sheet. Attractive van der Waals interactions are responsible for binding hydrogen molecules around the lithium atoms. Each lithium atom can adsorb three hydrogen molecules on both sides of the sheet, with an average hydrogen binding energy of approximately 0.2 eV, which is in the range required for practical applications. The BC2NBC-Li and BC2NCN-Li complexes can serve as high-capacity hydrogen-storage media with gravimetric hydrogen capacities of 9.88 and 9.94 wt %, respectively.
authors: College of Chemistry, Key Laboratory of Green Chemistry and Technology, Ministry of Education, Sichuan University, Chengdu 610064 (P.R. China).
authors: Nian-xiang
authors: NX
authors: Qiu
authors: Cheng-hua
authors: CH
authors: Zhang
authors: Ying
authors: Y
authors: Xue
keywords: adsorption; boron-nitrogen compounds; hydrogen storage; lithium; nanomaterials