Graphene oxide/N-methyl-2-pyrrolidone charge-transfer complexes for molecular detection

Charge transfer complex (CTC) has been formed between photoluminescent graphene oxide (GO) as electron acceptor and N-methylpyrrolidone (NMP) as electron donor. Studies of UV absorption and photoluminescence (PL) suggest that the formation of CTC results in a red-shift of absorption and a new PL emission. Decay dynamics was described by time-resolved PL spectra and a clear ultrafast charge-transfer process was observed from the PL rise times. The PL of the CTC was sensitive to external components, allowing molecular detection of 7,7,8,8-tetracyanoquinodimethane and 1,3,5-trinitrobenzene up to hundred nanomolar concentration levels through the photoluminescence signals.