Shi Yebai, Ren Jie, Tang Hua, Chen Xihao
School of Electric and Electrical Engineering, Shangqiu Normal University, Shangqiu 476000, China.
Material Science and Engineering Department, City University of Hongkong, Hongkong 999077, China.
Langmuir. 2024 Feb 6. doi: 10.1021/acs.langmuir.3c03255.
Efficient storage media are crucial for practical applications of hydrogen, which is the most promising clean energy resource. In addition to possessing a highly reversible gravimetric capacity, the stability and superlight mass of potential storage media should not be underestimated. In this study, we exploit the light mass and unique puckered structure of penta-BCNs to design Li-decorated penta-BCNs for hydrogen storage via a series of first-principles calculations. Our results reveal that Li atoms can form stable chemical complexes with the surface of penta-BCNs with an average binding energy of -2.21 eV without causing deformation. Each Li@penta-BCN unit can physically adsorb up to 27H molecules, and the highest hydrogen storage capacity can reach 7.44 wt %, with an average adsorption energy of -0.16 eV/H, surpassing the target value of 5.5 wt % set by the U.S. Department of Energy. Further elaborate analysis of the electronic structure shows the polarization enhancement mechanism, which is caused by charge transfer from Li atoms to the penta-BCN surface. Our results indicate that Li-decorated penta-BCN could be a promising hydrogen storage material for further application and inspire the theoretical or experimental design of novel materials for clean energy.
高效存储介质对于氢气的实际应用至关重要，氢气是最具前景的清洁能源。除了具有高可逆的重量容量外，潜在存储介质的稳定性和超轻质量也不容小觑。在本研究中，我们利用五硼碳氮化物（penta-BCNs）的轻质量和独特褶皱结构，通过一系列第一性原理计算设计用于储氢的锂修饰五硼碳氮化物。我们的结果表明，锂原子可以与五硼碳氮化物表面形成稳定的化学复合物，平均结合能为-2.21 eV，且不会引起变形。每个Li@penta-BCN单元最多可物理吸附27个氢分子，最高储氢容量可达7.44 wt%，平均吸附能为-0.16 eV/H，超过了美国能源部设定的5.5 wt%的目标值。对电子结构的进一步详细分析揭示了极化增强机制，这是由锂原子向五硼碳氮化物表面的电荷转移引起的。我们的结果表明，锂修饰的五硼碳氮化物可能是一种有前途的储氢材料，可用于进一步应用，并为清洁能源新型材料的理论或实验设计提供灵感。
