Combined modulation of electrical and thermal transport properties in diamond (100) surfaces via reconstruction and passivation

The intrinsic metallicity of diamond (100) surfaces, arising from unsaturated dangling bonds, remains a critical bottleneck for their integration into high-performance electronic devices. Here, we conduct a systematic first-principles investigation into the modulation of electronic and thermal properties via surface reconstruction and chemical passivation, complemented by homogeneous nonequilibrium molecular dynamics simulations. Our results demonstrate that surface reconstruction via dangling-bond saturation drives a transition from metallic to semiconducting characteristics, with the 2 × 1 reconstruction exhibiting the lowest surface energy (0.294 eV/Å2) and optimal stability. Furthermore, the introduction of functional groups (–F, –H, –O, –OH, and –NH2) enables precise modulation of the band structure and work function of the diamond (100) surface. Among the investigated functional groups, the H-terminated surface stands out as the optimal configuration, achieving a high acoustic-phonon-limited hole mobility (∼2.09 × 104 cm2 V−1 s−1) while maintaining a remarkable thermal conductivity of 726.2 W m−1 K−1. Our findings provide critical theoretical guidance for the development of high-performance diamond-based power electronics and thermal management systems.