PdPSe: Component-Fusion-Based Topology Designer of Two-Dimensional Semiconductor

Novel 2D semiconductors play an increasingly important role in modern nanoelectronics and optoelectronics. Herein, a novel topology designer based on component fusion is introduced, featured by the submolecular component integration and properties inheritance. As expected, a new air-stable 2D semiconductor PdPSe with a tailored puckered structure is successfully designed and synthesized via this method. Notably, the monolayer of PdPSe is constructed by two sublayers via P-P bonds, different from 2D typical transition metal materials with sandwich-structured monolayers. With the expected orthorhombic symmetry and intralayer puckering, PdPSe displays a strong Raman anisotropy. The field-effect transistors and photodetectors based on few-layer PdPSe demonstrate good electronic properties with high carrier mobility of ≈35 cm² V⁻¹ s⁻¹ and a high on/off ratio of 10⁶, as well as excellent optoelectronic performance, including high photoresponsivity, photogain, and detectivity with values up to 1.06 × 10⁵ A W⁻¹, 2.47 × 10⁷%, and 4.84 × 10¹⁰ Jones, respectively. These results make PdPSe a promising air-stable 2D semiconductor for various electronic and optoelectronic applications. This work suggests that the component-fusion-based topology designer is a novel approach to tailor 2D materials with expected structures and interesting properties.