Bacterial pigments coupled TiO_2 -carbon nanohybrid: understanding the interfacial effect on enhanced Fluorescence

Deployment of engineered photoactive nanoparticles is of significant contemporary interest. In this context, especially the use of titania ( TiO_2 )-incorporated biomolecules in several solar-driven systems is of greater concern. This paper reports up-regulation of photon capture and enhancement of emission with time, tailoring a pigment-nanohybrid interface. A TiO_2 -carbon nano-hybrid was synthesized using green technology and tailored with pigments, harvested from the bacteria Rhodobacter capsulatus SB1003. The nano-bio-hybrid system shows a significant quantum yield for enhanced emission through absorbing light at 400 nm. The tailored interface is capable of showing an increase in fluorescence enhancement for only bacterial pigments. The structural and morphological analysis of the system was correlated using Raman and FTIR spectroscopy, while the fluorescence spectroscopic analysis, provided insights to determine the kinetic parameters of the emitted photons. The study shows the variation of the surface topology of TiO_2 -carbon nanohybrids can alter the photoinduced aggregation dynamics of the tailored pigments, causing differential fluorescence enhancement. In addition, the synergic bonding alters the energy band structure present in the synthesized nano-bio-interface that supports the separation of the induced charges, a affecting the electron-hole recombination. Furthermore, the present investigation provides a green approach to obtain a sustainable tool for regulated photon capture and energy transfer, indicating its application in opto-electronic fields.