Panigrahi Puspamitra, Kumar Ashok, Bae Hyeonhu, Lee Hoonkyung, Ahuja Rajeev, Hussain Tanveer
Centre for Clean Energy and Nano Convergence, Hindustan Institute of Technology and Science, Chennai 603103, Tamil Nadu, India.
Phys Chem Chem Phys. 2020 Jul 21;22(27):15675-15682. doi: 10.1039/d0cp01237h. Epub 2020 Jul 3.
By using first principles density functional theory simulations, we report detailed geometries, electronic structures and hydrogen (H) storage properties of boron nitride nanotubes (BNNTs) doped with selective polylithiated molecules (CLi). We find that unsaturated bonding of Li-1s states with BNNT significantly enhances the system stability and hinders the Li-Li clustering effect, which can be detrimental for reversible H storage. The H adsorption mechanism is explained on the basis of polarization caused by the cationic Li of CLi molecules bonded with BNNT. The incident H molecules are adsorbed with BNNT-nCLi through electrostatic and van der Waals interactions. We find that with a maximum of 5.0% of CLi coverage on BNNT, an H gravimetric density of up to 4.41 wt% can be achieved with adsorption energies in the range of -0.33 eV per H, which is suitable for ambient condition H storage applications.
通过使用第一性原理密度泛函理论模拟，我们报告了掺杂有选择性多锂化分子（CLi）的氮化硼纳米管（BNNTs）的详细几何结构、电子结构和储氢性能。我们发现Li-1s态与BNNT的不饱和键合显著增强了系统稳定性，并阻碍了Li-Li聚集效应，而这种效应可能对可逆储氢不利。基于与BNNT键合的CLi分子的阳离子Li引起的极化来解释H吸附机制。入射的H分子通过静电和范德华相互作用被BNNT-nCLi吸附。我们发现，在BNNT上CLi覆盖率最高为5.0%时，每H的吸附能量在-0.33 eV范围内，可实现高达4.41 wt%的H重量密度，这适用于环境条件下的储氢应用。
