Study of interfacial charge transfer in nanosemiconductor–molecule composites

Abstract

Interaction of sol-gel synthesized Ce-Ag-codoped ZnO (CSZO) nanocrystals with (E)-1-(naphthalen-1-yl)-2-styryl-1Hphenanthro [9,10-d]imidazole has been analysed. The synthesized nanocrystals and their composites with naphthyl styryl phenanthrimidazole have been characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy, X-ray diffractometry, X-ray photoelectron spectroscopy (XPS) lifetime and Fourier transform infrared spectroscopy and cyclic voltammetry. XPS shows doped silver and cerium in Ag 0 and Ce 4+ states, respectively . SEM and TEM images of CSZO nanoparticles show that they appear to be 3D trapezoid and cocoon-like shape. The selected area electron diffraction pattern supports the nanocrystalline character of the synthesized material. The percentages of doping of cerium and silver in CSZO are 0.54 (at.) and 0.34 (at.), respectively. From the energy levels of the materials used in the imidazole-CSZO composite, the dominant CT direction has been analysed. Theoretical investigation shows that the binding energy and energy gap of the imidazole composites are highly dependent on the nature of the silver oxide cluster and that charge transfer in the imidazole-Ag 4 O 4 composite is faster than the same in other composites. Molecular docking technique has also been carried out to understand the imidazole-DNA interactions. Figure 7. (a) Lifetime spectra of NSPI and NSPI-Ce-Ag-ZnO composites. (b) Cyclic voltammogram of NSPI and NSPI-Ce-Ag-ZnO composite. (c) FT-IR spectra of NSPI, bare pristine ZnO and NSPI-Ce-Ag-ZnO composite INTERFACIAL CHARGE TRANSFER IN NANOSEMICONDUCTOR-MOLECULE COMPOSITES

Interfacial Charge Transfer in Photoelectrochemical Processes

“…It is required to incorporate a co‐catalyst to form composites and heterojunctions with the primary catalyst to create large number of interfaces or contacts. The mechanism of interfacial charge transfer has been investigated, revealing that the catalytic activity on the surface of the photocatalyst improves significantly by having large number of interfaces . The catalytic performance of photocatalysts can be further controlled by tuning of these interfacial charge‐transfer processes .…”