PMID- 25671674
OWN - NLM
STAT- MEDLINE
DCOM- 20151203
LR  - 20150317
IS  - 1520-5851 (Electronic)
IS  - 0013-936X (Linking)
VI  - 49
IP  - 6
DP  - 2015 Mar 17
TI  - Photochemical transformation of graphene oxide in sunlight.
PG  - 3435-43
LID - 10.1021/es5047155 [doi]
AB  - Graphene oxide (GO) is promising in scalable production and has useful properties 
      that include semiconducting behavior, catalytic reactivity, and aqueous 
      dispersibility. In this study, we investigated the photochemical fate of GO under 
      environmentally relevant sunlight conditions. The results indicate that GO 
      readily photoreacts under simulated sunlight with the potential involvement of 
      electron-hole pair creation. GO was shown to photodisproportionate to CO2, 
      reduced materials similar to reduced GO (rGO) that are fragmented compared to the 
      starting material, and low molecular-weight (LMW) species. Kinetic studies show 
      that the rate of the initially rapid photoreaction of GO is insensitive to the 
      dissolved oxygen content. In contrast, at longer time points (>10 h), the 
      presence of dissolved oxygen led to a greater production of CO2 than the same GO 
      material under N2-saturated conditions. Regardless, the rGO species themselves 
      persist after extended irradiation equivalent to 2 months in natural sunlight, 
      even in the presence of dissolved oxygen. Overall, our findings indicate that GO 
      phototransforms rapidly under sunlight exposure, resulting in chemically reduced 
      and persistent photoproducts that are likely to exhibit transport and toxic 
      properties unique from parent GO.
FAU - Hou, Wen-Che
AU  - Hou WC
AD  - daggerNational Research Council Associate, National Exposure Research Laboratory, 
      Ecosystems Research Division, U.S. Environmental Protection Agency, Athens, 
      Georgia 30605, United States.
AD  - double daggerDepartment of Environmental Engineering, National Cheng Kung University, Tainan 
      City 70101, Taiwan.
FAU - Chowdhury, Indranil
AU  - Chowdhury I
AD  - daggerNational Research Council Associate, National Exposure Research Laboratory, 
      Ecosystems Research Division, U.S. Environmental Protection Agency, Athens, 
      Georgia 30605, United States.
FAU - Goodwin, David G Jr
AU  - Goodwin DG Jr
AD  -  section signDepartment of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, 
      United States.
FAU - Henderson, W Matthew
AU  - Henderson WM
AD  -  perpendicularNational Exposure Research Laboratory, Ecosystems Research Division, U.S. 
      Environmental Protection Agency, Athens, Georgia 30605, United States.
FAU - Fairbrother, D Howard
AU  - Fairbrother DH
AD  -  section signDepartment of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, 
      United States.
FAU - Bouchard, Dermont
AU  - Bouchard D
AD  -  perpendicularNational Exposure Research Laboratory, Ecosystems Research Division, U.S. 
      Environmental Protection Agency, Athens, Georgia 30605, United States.
FAU - Zepp, Richard G
AU  - Zepp RG
AD  -  perpendicularNational Exposure Research Laboratory, Ecosystems Research Division, U.S. 
      Environmental Protection Agency, Athens, Georgia 30605, United States.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20150227
PL  - United States
TA  - Environ Sci Technol
JT  - Environmental science & technology
JID - 0213155
RN  - 0 (Oxides)
RN  - 059QF0KO0R (Water)
RN  - 142M471B3J (Carbon Dioxide)
RN  - 7782-42-5 (Graphite)
SB  - IM
MH  - Carbon Dioxide/chemistry
MH  - Graphite/*chemistry
MH  - Kinetics
MH  - Oxides/*chemistry
MH  - Photochemistry
MH  - *Sunlight
MH  - Water/chemistry
EDAT- 2015/02/12 06:00
MHDA- 2015/12/15 06:00
CRDT- 2015/02/12 06:00
PHST- 2015/02/12 06:00 [entrez]
PHST- 2015/02/12 06:00 [pubmed]
PHST- 2015/12/15 06:00 [medline]
AID - 10.1021/es5047155 [doi]
PST - ppublish
SO  - Environ Sci Technol. 2015 Mar 17;49(6):3435-43. doi: 10.1021/es5047155. Epub 2015 
      Feb 27.