The red spectrum in Figure  4a shows the work Linsitinib in vivo function of the GOx surface, showing that the secondary electron edge had shifted by 220 meV (Δϕ = 0.22 eV) toward higher kinetic energies relative to the monolayer EG secondary electron edge. This result indicated that the oxygen carriers on the GOx surface acted as p-type dopant materials. After measuring the GOx surface work function, a 3,600 L selleck compound aniline coverage was deposited at 300 K (the green spectrum in Figure  4a) on the GOx surface. Interestingly, this spectrum showed that the secondary electron edge had shifted by 300 meV (Δϕ = −0.30 eV) toward

lower kinetic energies relative to the pristine monolayer EG, indicating n-type doping due to aniline. The amine group in the aniline donated an electron carrier to the GOx surface, indicating that aniline acted as an electron dopant on the EG surface selleck (n-type characteristic). The blue spectrum in Figure  4a shows the secondary electron edge obtained after deposition of 10,800 L aniline at 300 K. Because the oxidation reaction proceeded more extensively at this exposure level, the edge was shifted by 80 meV (Δϕ = 0.08 eV) toward higher kinetic energies relative to the pristine monolayer EG. Unlike aniline, azobenzene acted as an electron acceptor (p-type characteristic). The presence of azobenzene on the GOx surface resulted in p-type doping carriers. Because

aniline and azobenzene were in competition on the GOx surface, the secondary electron edge did not show a significant shift toward higher kinetic energies. Finally, the aniline coverage level was increased to 14,400 L at 300 K (the purple spectrum in Figure  4a). The secondary electron edge was shifted by 180 meV (Δϕ = 0.18 eV) to higher kinetic energies relative to the pristine monolayer EG. This surface yielded a work function that resembled the work function of the GOx surface.

These results could be readily explained in terms of the aniline coverage. At higher coverage, the reaction GBA3 rate increased, thereby facilitating the oxidation of aniline to azobenzene. Figure  4b shows the dramatic change in the work function as a function of the aniline coverage. Figure 4 The several data acquired from HRPES experiments. (a) Work function measurements and (b) a plot of the work function values for each sample (a: monolayer EG, b: GOx surface, c: 3,600 L aniline, d: 10,800 L aniline, e: 14,400 L aniline). (c) Valence band spectra of the five samples. Black curve, monolayer EG; red curve, GOx surface prepared using benzoic acid; green curve, 3,600 L aniline; blue curve, 10,800 L aniline; and purple, 14,400 L aniline. (d) The magnified Fermi edge spectrum, which corresponds to Figure  4c. Figure  4c shows the valence band spectra of the five samples. The spectra are colored as in Figure  4a.