Hydrothermally derived reduced and hierarchically porous biochar for rapid and sensitive electrochemical detection of benzo[a]pyrene

Benzo[a]pyrene (BaP), as a typical polycyclic aromatic hydrocarbon, is severely hazardous to human for having great carcinogenic and teratogenic activities. Here, we propose a cascade electrochemical reaction-based BaP detection method by using novel synthesized reduced and hierarchically porous biochar (RP-BC) as conductive and analysts binding material. The RP-BC was synthesized by green hydrothermal reduction of sugarcane derived biochar, which was demonstrated to have huge specific surface area with hierarchically porous structures, great content of sp(2) carbon, and fast electron transfer ability. The RP-BC film coated on glassy carbon electrode could preferentially adsorb and enrich BaP by strong pi-pi electron donor-acceptor (EDA) interaction and pore interception effect, so fast (5 min) and selective detection of BaP was achieved. Moreover, the low detection limit was 0.090 nmol.mL(-1) with linear range being 0.32 to 80 nmol.mL(-1). In addition, the detection of BaP in groundwater and tap water was realized with satisfactory results, suggesting the potential of practical environmental monitoring.

Automated summary

In this study, a cascade electrochemical reaction-based BaP detection method was proposed using novel synthesized reduced and hierarchically porous biochar (RP-BC) as the conductive and analyte binding material. The RP-BC film coated on a glassy carbon electrode selectively adsorbs and enriches BaP through strong pi-pi electron donor-acceptor (EDA) interaction and pore interception effect, enabling fast (5 min) and selective detection. The method shows a low detection limit of 0.090 nmol.mL(-1) and a linear range of 0.32 to 80 nmol.mL(-1). BaP detection in groundwater and tap water was successfully achieved, suggesting its potential for practical environmental monitoring.