Graphene Assisted Photodegradation of ‎Pollutant Dyes and its Pragmatic Effect on ‎Lemna Minor and Eichhornia Crassipes ‎

Graphene assisted photodegradation have been used extensively as a remedial measure against pollutant dyes over last few years. The present work highlighted the comparative photodegradation effects between functionalized graphene oxide (GO) and nonfunctionalized graphene (Gr) maintained at room temperature (~27◦C) against three different pollutant dyes viz. malachite green (MG), methylene blue (MB) and methyl orange (MO) under visible light exposure at neutral medium (pH ~ 7). The degradation of MG and MB were remarkably high upon using the functionalized GO while nonfunctionalized Gr had comparatively less degradation efficiency against both these dyes. On the other hand, Gr was found to be effective than GO in combatting the azoic MO dye due to poor recombination of carrier charges. The photodegradation of 1:1:1 mixture of MG:MB:MO (dye cocktail) was studied in presence of GO, separated in HPLC to estimate the degradation efficiency of each dye. The mineralized products obtained from the LCMS/MS suggested the fragmentations in each dye occurred via demethylation route followed by asymmetric cleaving.  In realtime, the growth assessment of Lemna Minor and Eichhornia crassipes was monitored in dye cocktail alone and in presence of GO treated dye cocktail.