When the irradiation is stopped, the I-V characteristics of the device can be restored completely. HRTEM (Figure 2) has shown that the PbTe/Pb nanostructure is composed of semiconductor PbTe grains and metal Pb. In general, semiconductor grains embedded in the metal could effectively
increase the resistance because of the scattering action due to the crystal boundary potential barrier. As PbTe is a narrow bandgap semiconductor, when the PbTe/Pb nanostructure was irradiated by the 532-nm wavelength laser, light irradiation could not only reduce the height of the crystal boundary potential barrier in PbTe/Pb nanostructure, but also generate more carriers. Figure 6a shows the carrier generation mechanism schematic
diagram in the PbTe/Pb nanostructure GW-572016 price under light irradiation. The two factors could result in the increase of PbTe/Pb nanostructure conductivity. The I-V curves of the PbTe/Pb nanostructure arrays before and after assembling the Zn x Mn1−x S nanoparticles are shown in Figure 4b. The I-V curves indicate that the assembly of the Zn x Mn1−x S nanoparticles further increases the through current under the same laser irradiation. The performance of the PbTe/Pb-based nanocomposite had an obvious increase compared to that of the individual PbTe/Pb nanomaterial. When PF-3084014 chemical structure the PbTe/Pb-based nanocomposite is irradiated by the 532-nm wavelength laser, the nanoparticles coated on the surface could be excited. The electron that absorbed photon see more energy would first jump to the conduction band from the valence band in the Zn x Mn1−x S nanoparticles. Due to the differences in the work functions of materials, the carriers would transfer between the two mutual contact materials. For the two materials constituting the PbTe/Pb-based nanocomposite, the electron would transfer from the
Fermi-level higher Zn x Mn1−x S nanoparticle surface to the Fermi-level lower PbTe/Pb nanostructure surface, which would increase the carrier amount of the nanocomposite. In addition, the Zn x Mn1−x S nanoparticle is an important dilute magnetic semiconductor, and its bandgap can be adjusted by the doped contents of Mn2+ ions; the doping of Mn2+ ions brings the different electronic energy Phloretin levels for Zn x Mn1−x S nanoparticles. When the excited electrons in the high energy level jump to the low energy level, the excess energy would be released in the form of photons. These released photons, together with the photons from the laser, would excite the PbTe grains in the PbTe/Pb nanostructure, so the excited carrier amount in the PbTe/Pb-based nanocomposite is more than that in the PbTe/Pb nanostructure. The detailed carrier generation mechanism schematic diagram in the PbTe/Pb-based nanocomposite is shown in Figure 6b.