Low-dimensional phase engineering

By precisely controlling the phases in materials with reduced dimensionality, the material properties can be tailored, leading to enhanced performance and multifunctionality.

The practical application of 2D transition metal dichalcogenides (TMDs) requires robust and scalable synthesis of these atomically thin materials and their heterostructures. This Review discusses the key challenges, current progress and opportunities in the controllable synthesis of TMD-based heterostructures, superlattices and moiré superlattices.

Metastable pentagonal two-dimensional PdTe₂ is grown and stabilized on a Pd(100) surface through lattice-symmetry-driven epitaxy.

Monolayers of metastable 1T′-phase transition metal dichalcogenides can be rapidly grown and stabilized on 4H-phase gold nanowires, providing a hybrid system for ultrasensitive surface-enhanced Raman scattering detection.

A phase engineering strategy, using a device configuration consisting of 2D channel materials and patterned electrodes, has been demonstrated. It achieves various phase configurations of 2D materials and versatile functions that can be tailored in situ.

A metastable pentagonal PdTe₂ monolayer has been synthesized through symmetry-driven epitaxy, utilizing lattice matching with a Pd(100) substrate. The lattices, phonons and electronic structures of this phase have been studied.

High-phase-purity and stable 1T′-transition metal dichalcogenide monolayers are grown on 4H-Au nanowires by a facile and rapid wet-chemical method, enabling ultrasensitive surface-enhanced Raman scattering detection.

Helical motifs in dense inorganic solids have remained exceedingly scarce. Now a type of 1D van der Waals helical crystal, GaSeI, is presented that manifests the rare quasi-periodic Boerdijk–Coxeter helix motif.

A strategy of on-device phase engineering of two-dimensional materials is proposed, allowing the in situ realization of various lattice phases with distinct stoichiometries and versatile functions.