An Electrochemical Sensor Based on a Porous Biochar/Cuprous Oxide (BC/Cu 2 O) Composite for the Determination of Hg(II).

Mercuric ion (Hg 2+ ) in aqueous media is extremely toxic to the environment and organisms. Therefore, the ultra-trace electrochemical determination of Hg 2+ in the environment is of critical importance. In this work, a new electrochemical Hg 2+ sensing platform based on porous activated carbon (BC/Cu 2 O) modified with cuprous oxide was developed using a simple impregnation pyrolysis method. Differential pulse anodic stripping voltammetry (DPASV) was used to investigate the sensing capability of the BC/Cu 2 O electrode towards Hg 2+ . Due to the excellent conductivity and large specific surface area of BC, and the excellent catalytic activity of Cu 2 O nanoparticles, the prepared BC/Cu 2 O electrode exhibited excellent electrochemical activity. The high sensitivity of the proposed system resulted in a low detection limit of 0.3 ng·L -1 and a wide linear response in the ranges from 1.0 ng·L -1 to 1.0 mg·L -1 . In addition, this sensor was found to have good accuracy, acceptable precision, and reproducibility. All of these results show that the BC/Cu 2 O composite is a promising material for Hg 2+ electrochemical detection.