Photocatalytic Reduction of CO 2 to Fuel Using A Novel I-TiO 2 Based Catalyst Zixuan Wang, Chemical Engineering Mentor: Dr. Jean Andino School of Engineering Matter, Transport and Energy FUTURE WORK REFERENCES ACKNOWLEDGEMENTS SYNTHESIS BACKGROUND • Purpose: interest in reducing CO 2 emissions, which has been shown to cause global climate change • TiO 2 is most stable, cost-effective, and non- toxic catalyst used [1] • However, TiO 2 only responds to UV, whereas I-TiO 2 can expand to visible spectrum [2] • Re-energize CO 2 using a I-TiO 2 photocatalyst and RGO mixture oI-TiO 2 used since doping nonmetal materials into the TiO 2 have been shown to be effective in enhancing visible light activity [2] oRGO used to assist in charge separation • Study the formation of products such as methane (CH 4 ), carbon monoxide (CO), or other products on the surface of the catalyst • Perform experiment with heat treated novel catalyst at 220°C • Experiments with different illumination sources Special thanks to Dr. Jean Andino, Selisa Rollins, and Alejandro Castaneda and the FURI program at Arizona State University. We gratefully acknowledge the use of facilities within the LeRoy Eyring Center for Solid State Science at ASU. [1] Fujishima, A., et al. Comptes Rendus Chimie (2006) 9, 750-760 [2] Zhang Q., et al. Applied Catalysis A: General (2011) 400, 195-202 [3] Armaroli T. et al. Oil & Gas Science and Technology (2004), 215-237 Figure 1: Model of the photoreduction process RESULTS Figure 5: Dome interior of DRIFTS CHARACTERIZATION • Used XRD (X-Ray Diffraction) to characterize the crystal structure of I-TiO 2 EXPERIMENT 0 200 400 600 800 1000 1200 1400 0 20 40 60 80 Intensity 2θ XRD of I-TiO 2 at 400 C 400 °C: sample contained 75% anatase, 25% rutile 500 °C: sample contained 50% anatase, 50% rutile Figure 3: XRD characterization results of I-TiO 2 calcinated at 400 ºC with labeled anatase (A) and rutile (R) peaks Figure 4: XRD characterization results of I-TiO 2 calcinated at 500 ºC with labeled anatase (A) and rutile (R) peaks Figure 1: Model of photoreduction process Figure 2:Synthesis protocol for novel photocatalyst 0 200 400 600 800 1000 1200 1400 0 20 40 60 80 100 Intensity 2θ XRD of I-TiO 2 at 500 C A(101) R(110) A(101) R(110) Methodology Diffused Reflectance Infrared Fourier Transform spectroscopy (DRIFTs): -5:1 molar ratio of H 2 O/CO 2 flow -~50-60 mg of novel catalyst was used -illumination for 60 minutes with UV-vis light -sample collected every 10 minutes RESULTS Figure 7: DRIFTs spectra of OH region with H 2 O/CO 2 flow over 1 hour of illumination Figure 6: DRIFTs spectra of RGO-I-TiO 2 with H 2 O/CO 2 flow over 1 hour of illumination Figure 8: Subtracted DRIFTs spectra of RGO-I-TiO 2 with H 2 O/CO 2 flow over 1 hour of illumination Figure 9: Subtracted DRIFTs spectra of carbonate region with H 2 O/CO 2 flow over 1 hour of illumination • Spectra in Figures 6-9 were obtained from the DRIFTs experiment with RGO-I-TiO 2 composite catalyst • Decrease in CO 2 between 2300-2400 cm -1 • Intermediate product formation in OH (3000-3800 cm -1 ) and carbonate region (1200-1750 cm -1 )