Electronic Transport of MoS₂ Monolayered Flakes Investigated by Scanning Electrochemical Microscopy

The amazing properties of 2D materials are envisioned to revolutionize several domains such as flexible electronics, electrocatalysis, or biosensing. Herein we introduce scanning electrochemical microscopy (SECM) as a tool to investigate molybdenum disulfide in a straightforward fashion, providing localized information regarding the electronic transport within chemical vapor deposition (CVD)-grown crystalline MoS₂ single layers having micrometric sizes. Our investigations show that within flakes assemblies some flakes are well electrically interconnected, with no detectable contact resistance, whereas others are not electrically connected at all, independent of the size of the physical contact between them. Overall, the work shows how the complex electronic behavior of MoS₂ flake assemblies (semiconducting nature, contact quality between flakes) can be investigated with SECM.