Transition-Metal-Enhanced Hydrogen Adsorption on CNNCs: A DFT Analysis

Abstract

Due to Growing concerns regarding fossil fuel depletion and the environmental impact of their high consumption necessitate intensified research into renewable and clean alternatives, such as hydrogen, to meet Department of Energy (DOE) targets. In this study, the density functional theory calculations applying 6-31g(d,p) at B3LYP level comprehensively investigate carbon nanocones (CNCs) doped with Cu, Ti, Zn, and V. The analysis encompasses the electronic properties of structures featuring two disclination angles as a function of nanocones size. Furthermore, the mechanism of monohydrogen atom adsorption onto these doped CNC systems is examined. Computational results identify the Vdoped C75H9 structure with a 300° disclination angle as the most promising candidate for hydrogen storage. Additionally, the adsorption of hydrogen is found to reduce the electronic band gap energy. These findings collectively indicate that doped carbon nanocones represent a viable candidate material for hydrogen storage applications.