TiO2 Nanoparticles Incorporated Peptide Appended Perylene Bisimide-Based Nanohybrid System: Enhancement of Photo-Switching Behavior

Abstract

A peptide appended perylene bisimide (PBI) based new hydrogel has been discovered in phosphate buffer medium having the pH ranging from 7.00 to 9.00. This peptide appended PBI-derivative shows interesting photo-switching property in the aggregated state. This gel is thoroughly characterized by UV-Visible absorption and fluorescence spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM), High Resolution Transmission Electron Microscopy (HR-TEM), X-ray Ray Diffraction (XRD) and Rheological studies. TiO2 nanoparticles are also prepared by using a protein amino acid, glutamic acid in water medium. The as-synthesized TiO2 nanoparticles exhibit usual photo-switching behavior. An organic-inorganic hybrid nanomaterial is prepared by incorporating the as-synthesized TiO2 nanoparticles into the fibrillar gel network of the native gel. This TiO2-PBI-based hybrid soft material shows a characteristic of nanofiber and nanoparticle combination in their nanoscale co-assembled state as it is evident from the respective TEM images of the hybrid material. Interestingly, this nanohybrid shows improved photoswitching properties (photocurrent gain) compared to that of its individual constituents (TiO2 nanoparticles and PBI-based xerogel). The increase in photo-switching property holds a future promise for making a new organic-inorganic hybrid material for the optoelectronic device application with high a photo-current conversion efficiency.