Figure 4
Large-scale fabrication of a Schottky-type solar cell with few-layered WS2. (a,b) (a) Typical fabrication process of a large-scale solar cell with our method and (b) optical microscope image of CVD-grown WS2 used in this study. (c,d) (c) Low- and (d) high-magnification images of a large-scale Schottky type solar cell on a SiO2 substrate. Multiple solar cell units with asymmetric electrode pairs (Ni-Pt) were patterned over the entire substrate region. (e,f) (e) High-magnification optical microscope image and (f) PL intensity mapping of specific channel and electrode regions in an asymmetric electrode device. (g) Optical image of a Schottky-type solar cell with few-layered WS2 fabricated on a transparent and flexible substrate. Inset in (g) shows the high magnification OM image of WS2 briding between Pt and Ni electrode on a PEN substrate. (h,i) Typical I ds − V ds features with and without light (solar simulator) illumination for a specific asymmetric device fabricated on a large (h) SiO2 substrate and (i) PEN substrate. Inset in (i) denotes I ds − V ds curve of the PEN device measured by different power of solar simulator (black: 0, blue: 0.05 W/cm2, green: 0.1 W/cm2, orange: 0.14 W/cm2, red: 0.2 W/cm2). (j) Transparent spectra of a WS2-based solar cell with an asymmetric electrode on a PEN substrate. (k) Comparison of transparency vs. PCE with our TMD-based device and other organic solar cells. Data of ○ (i)–(ix) are replotted using the data from ref.1,2,4,31,32,33,34,35 respectively.
