Self-assembly of osmium complexes on reduced graphene oxide: A case study toward electrochemical chiral sensing

An electrochemical sensor was constructed via self-assembly of chiral metal complexes Λ-[Os(phen)3(ClO4)2] on reduced graphene oxide (rGO) sheet. Cyclic voltammetry and differential pulse voltammetry illustrate that the sensor could detect 1,1′-2-binaphthol lower than 10 μM. The response current of S-1,1′-2-binaphthol is 1.4 times higher than that of R-1,1′-2-binaphthol. A linear concentration range was attained for the response peak current. In comparison to clay/indium tin oxide substrate based chiral sensor, rGO has clearly enhanced the sensitivity of chiral sensing. Preliminary measurement indicates that the rGO/Λ-[Os(phen)3]2 + sensor can also be applied to determine compositions of a chiral mixture.

► Prepared functionalized hybrid film based on reduced graphene oxide. ► The hybrid film exhibited greatly improved sensitivity and selectivity in chiral sensing. ► There is a linear relationship between the peak current and the concentration of chiral moleculs. ► The as-prepared sensor could analyze a mixture of binaphthol chiral molecules.