2+δ-Dimensional Materials via Atomistic Z-Welding.

Abstract

Pivotal to functional van der Waals stacked flexible electronic/excitonic/spintronic/thermoelectric chips is the synergy amongst constituent layers. However; the current techniques viz. sequential chemical vapor deposition, micromechanical/wet-chemical transfer are mostly limited due to diffused interfaces, and metallic remnants/bubbles at the interface. Inter-layer-coupled 2+δ-dimensional materials, as a new class of materials can be significantly suitable for out-of-plane carrier transport and hence prompt response in prospective devices. Here, the discovery of the use of exotic electric field ≈106 Vcm- 1 (at microwave hot-spot) and 2 thermomechanical conditions i.e. pressure ≈1MPa, T≈ 200°C (during solvothermal reaction) to realize 2+δ-dimensional materials is reported. It is found that Pz Pz chemical bonds form between the component layers, e.g., CB and CN in G-BN, MoN and MoB in MoS2 -BN hybrid systems as revealed by X-ray photoelectron spectroscopy. New vibrational peaks in Raman spectra (BC ≈1320cm-1 for the G-BN system and MoB ≈365cm-1 for the MoS2 -BN system) are recorded. Tunable mid-gap formation, along with diodic behavior (knee voltage ≈0.7V, breakdown voltage ≈1.8V) in the reduced graphene oxide-reduced BN oxide (RGO-RBNO) hybrid system is also observed. Band-gap tuning in MoS2 -BN system is observed. Simulations reveal stacking-dependent interfacial charge/potential drops, hinting at the feasibility of next-generation functional devices/sensors.