This paper describes the small‐angle scattering beamline built at the Brazilian Synchrotron Light Laboratory (LNLS). Vertical focusing of the synchrotron beam is achieved by an elastically bent gold‐plated cylindrical mirror. An asymmetric cut curved triangle‐shaped silicon single crystal (111 reflection) is used for monochromatization and horizontal focusing. The mirror, monochromator optics and 2θ arm were designed to cover the spectral range between 1.0 and 2.0 Å. Three slit sets, a secondary photon shutter, two beam monitors, filters and absorbers, a multi‐sample holder, a vacuum path, a beam‐stopper and a set of detectors are the basic components of the workstation. The stepping motors are equipped with specially designed encoders. All mechanical and pneumatic movements and detectors can be remotely controlled using a direct panel or a PC.

The soft X‐ray spectroscopy beamline installed at a bending‐magnet source in the LNLS is presented. A technical description of the main elements is given and some selected commissioning results are shown. The beamline optics was designed to cover the soft X‐ray energy range from 790 up to 4000 eV. The bending‐magnet source has a critical energy of 2.08 keV and delivers ∼1012 photons s−1 mradH−1 (0.1% bandwidth)−1 (100 mA)−1. The focusing element is a gold‐coated toroidal mirror operating at an angle of incidence of 1°. The double‐crystal monochromator has three pairs of crystals which can be selected by a lateral translation. The UHV experimental station is equipped with an ion gun, an electron gun, a LEED optics and an electron analyser. The beamline is intended for X‐ray absorption, photoemission, reflectivity and dichroism experiments. The beamline has been installed, commissioned, and is now open to the external users community.

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Two-dimensional van der Waals heterostructures are attractive candidates for optoelectronic nanodevice applications. The charge transport process in these systems has been extensively investigated, however the effect of coupling between specific electronic states on the charge transfer process is not completely established yet. Here, interfacial charge transfer (CT) in the MoS/graphene/SiO heterostructure is investigated from static and dynamic points of view. Static CT in the MoS-graphene interface was elucidated by an intensity quenching, broadening and a blueshift of the photoluminescence peaks. Atomic and electronic state-specific CT dynamics on a femtosecond timescale are characterized using a core-hole clock approach and using the S1s core-hole lifetime as an internal clock. We demonstrate that the femtosecond electron transfer pathway in the MoS/SiO heterostructure is mainly due to the electronic coupling between S3p-Mo4d states forming the Mo-S covalent bond in the MoS layer. For the MoS/graphene/SiO heterostructure, we identify, with the support of density functional calculations, new pathways that arise due to the high density of empty electronic states of the graphene conduction band. The latter makes the transfer process time in the MoS/graphene/SiO/Si twice as fast as in the MoS/SiO/Si sample. Our results show that ultrafast electron delocalization pathways in van der Waals heterostructures are dependent on the electronic properties of each involved 2D material, creating opportunities to modulate their transport properties.