Figure 1

Solar cell of few-layer WSe2 with a symmetric electrode. (a) Schematic illustration of the device structure. (b–g) Typical (b) AFM image, (c) height profile, (d) optical microscope image, (e) Raman intensity mapping image, (f) Raman scattering spectra, and (inset in f) PL spectra of few-layered WSe2. (g) I ds − V ds characteristics of few-layered WSe2 with (red) and without (black) right (solar simulator) illumination.