First-principles study on the electronic and mechanical properties of 2D C6H4 and its 1D derivative
Abstract
Two-dimensional (2D) semiconductors with wide bandgaps and robust stability are essential for next-generation electronic devices. Herein, leveraging the stackability of 2D materials, we constructed a novel carbon-hydrogen monolayer, o-C6H4. Our first-principles calculations reveal that it exhibits excellent thermal stability, a high Young’s modulus, and a negative Poisson’s ratio. o-C6H4 is identified as a wide-bandgap semiconductor with a bandgap of 4.03 eV. Ideal tensile tests show that the critical strains along the a-axis, b-axis, and biaxial directions are 0.17, 0.145, and 0.155, respectively, and its mechanical failure is dominated by elastic instability rather than phonon softening. Furthermore, inspired by the ideal tensile results, we explored one-dimensional nanowires (1D-C6H4) derived from the o-C6H4 parent phase and systematically characterized their stability and electronic behavior. This work not only introduces a promising 2D/1D hydrocarbon system but also provides a viable strategy for designing low-dimensional carbon-based semiconductors.