Dongmok Whang

Molybdenum disulfide (MoS₂) presents fascinating properties for next-generation applications in diverse fields. However, fully exploiting the best properties of MoS₂ in largescale practical applications still remains a challenge due to lack of proper processing methods. Solution-based processing can be a promising route for scalable production of MoS₂ nanosheets, but the resulting assembled film possesses an enormous number of interfaces that significantly compro

The synthesis of uniform low-defect graphene on a catalytic metal substrate is getting closer to the industrial level. However, its practical application is still challenging due to the lack of an appropriate method for its scalable damage-free transfer to a device substrate. Here, an efficient approach for a defect-free, etchant-free, wrinkle-free, and large-area graphene transfer is demonstrated by exploiting a multifunctional viscoelastic polymer gel as a simultaneous shock-free adhesive and

In MoS₂-carbon composite catalysts for hydrogen evolution reaction (HER), the carbon materials generally act as supports to enhance the catalytic activity of MoS₂ nanosheets. The carbon support provides a large surface area for increasing the MoS₂ edge site density, and its physical structure can affect the electron transport rate in the composite catalysts. However, despite the importance of the carbon materials, direct observation of the effects of the physical

Flexible transparent conducting electrodes (FTCE) are an essential component of next-generation flexible optoelectronic devices. Graphene is expected to be a promising material for the FTCE, because of its high transparency, large charge carrier mobilities, and outstanding chemical and mechanical stability. However, the electrical conductivity of graphene is still not good enough to be used as the electrode of an FTCE, which hinders its practical application. In this study, graphene was heavily

Two-dimensional semiconductor heterostructures provide significant research potential for electronic and optoelectronic applications because of their scaled thickness, pristine heterostructure interface, and ultrafast carrier transport. Herein, we report a dual-channel field-effect transistor based on n-type WS2 and p-type WSe2 layered heterostructure using multilayered graphene as electrodes to enable electron-dominated ambipolar electrical transport. WS2 exhibits mobility of 20 cm2 V–1 s–1 and

We present a facile CMOS-compatible fabrication of lateral gate-all-around (GAA) field effect transistors (FETs) based on concentric Si-SiO₂/N(++)Si core-multi-shell nanowires (NWs). Si-SiO₂/N(++)Si core-multi-shell NWs were prepared by sequential Si NW growth, thermal oxidation and Si deposition processes in a single chamber. The GAA NW FET was then fabricated using the Si core, SiO₂ inner-shell, N(++) Si outer-shell as a channel, gate dielectric, and gate electrode, respectively. A one-step we

Core–shell Si_1−xGe_x alloy nanowires can suppress the phonon propagation without reducing the electrical conductivity.

Graphene growth on a copper surface via metal-catalyzed chemical vapor deposition has several advantages in terms of providing high-quality graphene with the potential for scale-up, but the product is usually inhomogeneous due to the inability to control the graphene layer growth. The non-uniform regions strongly affect the reliability of the graphene in practical electronic applications. Herein, we report a novel graphene transfer method that allows for the selective exfoliation of single-layer

A two-dimensional (2D) atomic crystalline transition metal dichalcogenides has shown immense features, aiming for future nanoelectronic devices comparable to conventional silicon (Si). 2D molybdenum ditelluride (MoTe₂) has a small bandgap, appears close to that of Si, and is more favorable than other typical 2D semiconductors. In this study, we demonstrate laser-induced p-type doping in a selective region of n-type semiconducting MoTe₂ field effect transistors (FET) with an