Controlled, defect-guided, metal-nanoparticle incorporation onto MoS2 via chemical and microwave routes: electrical, thermal, and structural properties.
Ultrathin (0.3-3 nm) metal dichalcogenides exhibit confinement of carriers, evolution of band-structure and photophysical properties with thickness, high on/off rectification (in MoS2, WS2, and so forth) and high thermal absorption. Here, we leverage the stable sulfur/nobel-metal binding to incorporate highly capacitive gold nanoparticles (Au NPs) onto MoS2 to raise the effective gate-voltage by an order of magnitude. Functionalization is achieved via both diffusion limited aggregation and instantaneous reaction arresting (using microwaves) with selective deposition on crystallographic edges (with 60° displacement). The electrical, thermal, and Raman studies show a highly capacitive interaction between Au NP and MoS2 flakes (CAu-MoS2 = 2.17 μF/cm(2)), a low Schottky barrier (14.52 meV), a reduced carrier-transport thermal-barrier (253 to 44.18 meV after Au NP functionalization), and increased thermal conductivity (from 15 to 23 W/mK post NP deposition). The process could be employed to attach electrodes to heterostructures of graphene and MoS2, where a gold film could be grown to act as an electron-tunneling gate-electrode connected to MoS2.
Department of Chemical Engineering, Kansas State University , 1005 Durland Hall, Manhattan, Kansas, 66502, United States.
T S
TS
Sreeprasad
Phong
P
Nguyen
Namhoon
N
Kim
Vikas
V
Berry
D004058:Diffusion; D004220:Disulfides / Q000737:chemistry*; D004566:Electrodes; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008872:Microwaves; D008982:Molybdenum / Q000737:chemistry*; D013499:Surface Properties
D004220:Disulfides; D006046:Gold; D006108:Graphite; D008982:Molybdenum; C082964:molybdenum disulfide