Gold-mediated exfoliation of MoS 2 has recently attracted considerable interest. The strong interaction between MoS 2 and Au facilitates preferential production of centimeter-sized monolayer MoS 2 with near-unity yield and provides a heterostructure system noteworthy from a fundamental standpoint. However, little is known about the detailed nature of the MoS 2 –Au interaction and its evolution with the MoS 2 thickness. Here, we identify the specific vibrational and binding energy fingerprints of this interaction using Raman and X-ray photoelectron spectroscopy, which indicate substantial strain and charge doping in monolayer MoS 2 . Tip-enhanced Raman spectroscopy reveals heterogeneity of the MoS 2 –Au interaction at the nanoscale, reflecting the spatial nonconformity between the two materials. Micro-Raman spectroscopy shows that this interaction is strongly affected by the roughness and cleanliness of the underlying Au. Our results elucidate the nature of the MoS 2 –Au interaction and guide strain and charge doping engineering of MoS 2 .

We present the first Raman spectroscopic study of Bernal bilayer graphene flakes under uniaxial tension. Apart from a purely mechanical behavior in flake regions where both layers are strained evenly, certain effects stem from inhomogeneous stress distribution across the layers. These phenomena such as the removal of inversion symmetry in bilayer graphene may have important implications in the band gap engineering, providing an alternative route to induce the formation of a band gap.

The electrochemical behavior of TiO2 anatase with a predominant (001) face (ANA001) was studied by cyclic voltammetry of Li insertion and chronoamperometry. Both voltammetric and chronoamperometric diffusion coefficients and rate constants proved the higher activity of ANA001 toward Li insertion compared to that of a reference anatase material (C240) with dominating (101) facets. The enhanced activity of the anatase (001) face for Li insertion stems from synergic contributions of a faster interfacial charge transfer at this surface and a facile Li transport within a more open structure of the anatase lattice in the direction parallel to the c -axis. Despite the larger particle size of ANA001, the values of integral charge capacity and Li-insertion coefficient further confirmed its improved Li-insertion properties. The results of this study further complete the analogous data published on single-crystal anatase electrodes and evidence their validity for nanocrystalline materials too.