First-principles study of Li-doped planar g-C3N5 as reversible H2 storage material

Frontiers in Chemistry

Chemistry

Jiwen Li¹  Guangzhao Wang²  Xianghong Niu³  Peng Gao⁴  Liang Zhang⁵  Donglin Guo⁶  Jiang Cheng⁶  Zonghang Liu⁷  Ning Wang⁸  Xihao Chen⁹ 

[1] College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou, China;Key Laboratory of Extraordinary Bond Engineering and Advanced Materials Technology of Chongqing, School of Electronic Information Engineering, Yangtze Normal University, Chongqing, China;New Energy Technology Engineering Laboratory of Jiangsu Province, School of Science, Nanjing University of Posts and Telecommunications, Nanjing, China;School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia;Molecular Horizons, University of Wollongong, Wollongong, NSW, Australia;School of Electric and Electrical Engineering, Shangqiu Normal University, Shangqiu, China;School of Materials Science and Engineering, Chongqing University of Arts and Sciences, Chongqing, China;School of Science and Engineering, Shenzhen Key Laboratory of Functional Aggregate Materials, The Chinese University of Hong Kong, Shenzhen, China;State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China;Chongqing Key Laboratory of Precision Optics, Chongqing Institute of East China Normal University, Chongqing, China;State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China;School of Materials Science and Engineering, Chongqing University of Arts and Sciences, Chongqing, China;Chongqing Key Laboratory of Precision Optics, Chongqing Institute of East China Normal University, Chongqing, China;

关键词: hydrogen storage;    reversible;    g-CN;    Li-decorated;    DFT;   

DOI  :  10.3389/fchem.2023.1301690

 received in 2023-09-25, accepted in 2023-10-11,  发布年份 2023

来源: Frontiers

【 摘 要 】

Under the background of energy crisis, hydrogen owns the advantage of high combustion and shows considerable environment friendliness; however, to fully utilize this novel resource, the major hurdle lies in its delivery and storage. The development of the in-depth yet systematical methodology for two-dimensional (2D) storage media evaluation still remains to be challenging for computational scientists. In this study, we tried our proposed evaluation protocol on a 2D material, g-C3N5, and its hydrogen storage performance was characterized; and with addition of Li atoms, the changes of its electronical and structural properties were detected. First-principles simulations were conducted to verify its thermodynamics stability; and, its hydrogen adsorption capacity was investigated qualitatively. We found that the charges of the added Li atoms were transferred to the adjacent nitrogen atoms from g-C3N5, with the formation of chemical interactions. Thus, the isolated metallic sites tend to show considerable electropositivity, and can easily polarize the adsorbed hydrogen molecules, and the electrostatic interactions can be enhanced correspondingly. The maximum storage capacity of each primitive cell can be as high as 20 hydrogen molecules with a gravimetric capacity of 8.65 wt%, which surpasses the 5.5 wt% target set by the U.S. Department of Energy. The average adsorption energy is ranged from −0.22 to −0.13 eV. We conclude that the complex 2D material, Li-decorated g-C3N5 (Li@C3N5), can serve as a promising media for hydrogen storage. This methodology provided in this study is fundamental yet instructive for future 2D hydrogen storage materials development.

【 授权许可】

Unknown   
Copyright © 2023 Chen, Liu, Cheng, Li, Guo, Zhang, Niu, Wang, Wang and Gao.