Figure 5: IPCE, power factor α, and dependence of photocurrent on light intensity on the graphene/TiO2 Schottky nanodiodes.
From: Hot carrier multiplication on graphene/TiO2 Schottky nanodiodes
(a) IPCE measured on the graphene/TiO2 Schottky nanodiodes after doping. (b) Power factor α obtained by fitting the IPCE to Fowler’s law as a function of doping. (c) Photocurrent measured on the Au/TiO2 and SLG/TiO2 Schottky nanodiodes as a function of light intensity. The photocurrent was measured as a function of the incident light intensity. The photocurrent of the SLG/TiO2 shows a very weak intensity dependence; at the low light intensity limit (<8 mW/cm2), the photocurrent of SLG/TiO2 is larger than that of Au/TiO2, resulting from efficient hot electron generation through CM at weak light intensity. The TETA-doped graphene/TiO2 shows the lowest intensity dependence of photocurrent, exhibiting an enhanced effect of CM by an increase in the effective impact ionization and internal photoemission from a decrease in the Schottky barrier. (d) The values of exponent n representing the relationship between photocurrent and light intensity.
