Electron Doping of Semiconducting MoS₂ Nanosheets by Silver or Gold Nanoclusters

Abstract

Semiconducting two-dimensional (2D) materials have potential applications as ultrathin optoelectronic materials. Therefore, being able to precisely modulate the band gap is useful to improving their applicability. Electron doping of the semiconducting materials is one of the successful techniques used to modulate their band gap. Silver nanoclusters (AgNCs) or gold nanoclusters (AuNCs) a few nanometers in size can generate a high density of highly energetic hot electrons with relatively long lifetimes when photoexcited. The optical band gap of 2D MoS2 nanosheets shows different responses when integrated with different amounts of AgNCs or AuNCs due to the electron doping effect. Introducing a small amount of the nanoclusters to the surface of a MoS2 nanosheet lowered its optical band gap. Further reduction of the optical band gap of MoS2 is obtained upon tripling the amount of integrated nanoclusters. Conversely, the optical band gap of MoS2 was increased when integrated with 5 times the concentration of AuNCs and AgNCs. The optical band gap of the MoS2 nanosheets was significantly increased when integrated with an even higher concentration of AuNCs or AgNCs. The magnitude of the shift of the optical band gap of MoS2 induced by AgNCs is higher than that induced by AuNCs because the energy of LUMO of the AgNCs is higher than that of the AuNCs.

Resolving the Heterogeneous Adsorption of Antibody Fragment on a 2D Layered Molybdenum Disulfide by Super-Resolution Imaging

“…The existence of these unwanted signals degrades the quality of optical microscopic images. The photoluminescence (PL) signal − from MoS 2 forms a constant background pattern in the fluorescence image (Figures d, S4, and S5), thus reducing the precision of localizing the photoswitchable dye molecule, AF647, labeled on the adsorbed HAFs at different structural features. The reconstructed dSTORM images in the presence of the constant background pattern (Figure g,j) include many falsely localized molecular positions.…”

Study on the Sliding Tribological Behavior of Oleic Acid-Modified MoS2 under Boundary Lubrication

“…In recent years, two-dimensional layered materials with ultrathin structures have shown good application prospects in lubrication, optics, electrochemistry, and catalysis due to their unique structures and excellent properties. , Many studies have shown that two-dimensional layered materials have an extremely high-load-bearing capacity and can easily enter the friction contact area due to their ultrathin thickness. − These materials remarkably affect friction and wear properties. , Two-dimensional MoS 2 nanosheet has the characteristics of a two-dimensional layered material and strong adsorption properties between the sulfur element exposed on the surface of MoS 2 and the metal surface. Thus, a tribochemical reaction film can be easily formed on the friction surface, which is ideal for high-performance lubricant additives.…”

“…In recent years, two-dimensional layered materials with ultrathin structures have shown good application prospects in lubrication, optics, electrochemistry, and catalysis due to their unique structures and excellent properties. 1,2 Many studies have shown that two-dimensional layered materials have an extremely high-load-bearing capacity and can easily enter the friction contact area due to their ultrathin thickness. 3−6 These materials remarkably affect friction and wear properties.…”