A facile avenue to prepare chiral graphene sheets as electrode modification for electrochemical enantiorecognition

Electrochemical enantiorecognition has attracted much interest due to its advantages of low cost and simple equipment. In this work, a new chiral ionic liquid is prepared and applied as an electrolyte for the one-step synthesis of functional graphene sheets (GO-(S,S)-CIL). More importantly, an electrode is modified by the material for the construction of an electrochemical sensor (GO-(S,S)-CIL-GCE). Enantiomers including L/D-tryptophan, (R)-/(S)-mandelic acid, (R)-/(S)-malic acid, and L/D-tyrosine are successfully distinguished by GO-(S,S)-CIL-GCE in the response of peak currents to different forms. In addition, the peak potential of the L form is located negatively compared to the D form for tryptophan, and the value of the peak-to-peak potential separation approaches 72 mV. The recognition mechanism is assessed by the density functional theory calculation in detail. In brief, the present method offers great promise for the preparation of functional graphene sheets and their further application in chiral recognition.