Fig. 4. Redox-modulated fluorescence sensing of Cr(vi) using N-Ti3C2 MQDs. (a) Fluorescence recovery of the quenched MQDs–Cr(vi) system upon the addition of ascorbic acid (AA). (b) Corresponding fluorescence recovery efficiency as a function of AA concentration with linear calibration inset. (c and d) Selectivity evaluation for Cr(vi) detection in the presence of common interfering ions. (e) Selectivity of fluorescence recovery toward AA over various potential reductants. Adapted with permission from ref. 71. © 2021, Elsevier B.V.
