This study reveals a concentration‐dependent adsorption where alkali ions Lithium (Li), sodium (Na), and potassium (K) preferentially occupy hollow sites at all concentrations. Their adsorption behaviour on armchair graphene nanoribbons (AGNRs) is systematically studied using density functional theory at concentrations of 2.7%, 5.2%, 7.6%, and 10%. Performance is analysed in terms of electronic structure (band structure and density of states), bond lengths (LiC, NaC, and KC), cohesive energy, adsorption energy, open‐circuit voltage (OCV), theoretical capacity and diffusion barriers. The results show increasing structural deformation with higher ion concentration. Li exhibits strong chemisorption at all concentrations while Na shows predominantly physisorption due to weaker interaction with AGNR electronic states. K mostly depicts chemisorption but induces significant lattice distortion due to its larger size. Li has the highest adsorption energy whereas Na shows lower adsorption than K due to less effective orbital interaction. All ions exhibit low diffusion barriers (<0.5 eV) indicating good mobility with Li giving highest barrier while K shows the lowest barrier and Na little higher than K. OCV calculations suggest suitability of all ions for anodes in battery applications. The study aims to provide new insights into adsorption limits in AGNRs.
Pundir et al. (Fri,) studied this question.