A black phosphorene (BPE) and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) hybrid was used for the immobilization of hemin on a carbon ionic liquid electrode (CILE). BPE inside the PEDOT:PSS film was stable without adverse effects of water and oxygen. The hemin-modified electrode facilitates electrochemical communication with a couple of well-shaped and enhanced redox waves. Therefore BPE exhibits an accelerating function to the electron movement. This sensor exhibits excellent electrocatalytic effects on the reduction of various substrates including trichloroacetic acid (TCA), nitrite and H2O2. As for TCA, the reduction current at -0.36 V (vs. Ag/AgCl) increases linearly in the concentration range from 2.0 to 180 mmol·L-1 with a detection limit of 0.67 mmol·L-1 (at 3σ). As for nitrite, the reduction current at -0.59 Vis linear in the 1.0 to 10.5 mmol·L-1 concentration range, and the detection limit is 0.33 mmol·L-1 (at 3σ). As for H2O2, the reduction current at -0.033 V (vs. Ag/AgCl) is linear in the concentration range from 4.0 to 35.0 mmol·L-1 and the detection limit is 1.3 mmol·L-1 (at 3σ). The real sample was analyzed with satisfactory results, which indicated that BPE had potential applications in the field of electrochemical biosensor. Graphical abstract Photos of (a) black phosphorene (BPE) solution, (b) poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS), (c) BPE-PEDOT:PSS (1:5) dispersion, and the fabrication procedure of this electrochemical sensor. It was applied to the determination of trichloroacetic acid, nitrite and hydrogen peroxide.
Keywords: Black phosphorene; Carbon ionic liquid electrode; Direct electrochemistry; Electrocatalytic effect; Electrochemical biosensor; Hemin; Hydrogen peroxide; Nitrite; Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate); Trichloroacetic acid.