Date/Time: 04-04-2018 - Wednesday - 05:00 PM - 07:00 PM
Anuja Bokare1 Sowbaranigha Jayanth1 Folarin Erogbogbo1

1, San Jose State University, San Jose, California, United States

Artificial photosynthesis aims at mimicking the natural photosystem II in plants, which splits water to oxygen and hydrogen, converting solar energy directly into chemical fuels. Among numerous engineered light absorbing and photosensitive materials, Titania (TiO2) is the most popular choice of semiconductor for photocatalysis, because it has high resistance to photocorrosion and stability when exposed to light. Furthermore, the appropriate valence and conduction band energies of TiO2 are best suited to overcome the thermodynamic and the electrochemical potential required for photoelectrolysis of water. However, TiO2 as a photo anode material faces some significant challenges such as poor absorption of visible light, high carrier recombination, and limited charge-carrier transport. To overcome these limitations, we synthesize and evaluate nano composite material using carbon based graphene quantum dots (GQDs) and TiO2 nano particles. The GQDs are synthesized by an inexpensive wet chemical method using bird charcoal as a precursor. GQD nanostructures exhibit band gap tunability based on their size and have the potential to enhance the photo absorption in TiO2. In particular, the hybrid combination of the nano materials decrease the recombination of charge carriers, increase charge carrier mobility and improve the overall photo-conversion efficiency. The synthesized nano composites are size and structure characterized using scanning electron microscope (SEM) image and atomic force microscope (AFM). Electrical/electronic performance of the composite is investigated by photocurrent density measurements. Further, optoelectronic properties are studied using photoluminescence (PL) spectrum and UV-visible transmission spectrum. The effect of using GQDs as a precursuor for TiO2 synthesis is also evaluated in contrast to TiO2.The use of this combination of nano materials is non-toxic, inexpensive, and novel for photo electrochemical (PEC) water splitting application and has implications for cost effective solar fuel cell developments.

Meeting Program

5:00 PM–7:00 PM Apr 4, 2018 (America - Denver)

PCC North, 300 Level, Exhibit Hall C-E