CREWS-JRW Team Meeting

Dec 14 2021 12:00 pm
WebEx Virtual Meeting
A stream running through a CREWS-JRW field site

The CREWS-JRW team will meet on Tuesday, December 14 at noon on WebEx.

Shelton Varapragasam, a CREWS postdoctoral researcher at MSU, will present at the Dec. 14 team meeting.

Photocatalytic reduction of aqueous nitrate with pristine g-C3N4 and  hybrid Ag/g-C3N4

Picture of Shelton Varapragasam. Photo credit: Skyler Hollinbeck

Talk description: This talk discusses ongoing efforts of photocatalytic nitrate reduction (PNR) on graphitic carbon nitride (g-C3N4) and silver-loaded graphitic carbon nitride (Ag/g-C3N4). While nitrate reduction does occur on the pristine material, the silver cocatalyst greatly enhances product yields.  At neutral pH, both pure g-C3N4 and Ag/g-C3N4 hybrid photocatalysts were studied, with the hybrid system exhibiting faster reduction rates under both visible and UV photoexcitation. Current efforts are directed toward further elucidation of the nitrate reduction mechanism. In particular, studies of PNR on Ag/g-C3N4 in different pH conditions show little that PH has little effect on product yield or reaction kinetics. We have also tested Ag/g-C3N4 as PNR photocatalyst in JRW nitrate-contaminated environmental samples. These results suggest that Ag/g-C3N4 will reduce contaminated nitrate in stream water, provided that sufficient DOC exists to supply electrons in the overall catalytic cycle.

About Shelton: Shelton Varapragasam graduated from the Vavuniya Campus of the University of Jaffna, Sri Lanka with a BS in Environmental Science. Then he earned his MS in Geo-Informatics from the University of Peradeniya, Sri Lanka. Later, he moved to US to pursue his Ph.D. in Materials Chemistry. He obtained MS in Chemistry and Ph.D. in Materials Chemistry from the University of South Dakota. During his stay at USD, he worked under Dr. James Hoefelmeyer, where he learned nanoscale engineering techniques of semiconductor materials and photocatalysis. Currently, he is working as Post-Doctoral Research Scientist under Dr. Erik Grumstrup for the Department of Chemistry and Biochemistry of Montana State University. As a research scientist, he is designing a hybrid photocatalyst and conducting photocatalytic nitrate reduction studies of the engineered photocatalyst.

Join from the meeting link: https://montana.webex.com/montana/j.php?MTID=m2efb69866c898f18ca40fcb64be6fd5e
Meeting number (access code): 120 724 7107 
Meeting password: UPypb33JPH5