A micro trace heavy metal sensor based on direct prototyping mesoporous carbon electrode

We present a micro trace heavy metal sensor based on bismuth-modified mesoporous carbon electrodes that are directly prototyped on silicon wafer. The novel device features a great electrochemical sensing platform for voltammetric analysis because the thicker mesoporous carbon electrode has high surface area, wide potential window, high electric conductivity, and can be integrated into microsystems. The sensor achieves excellent sensing performance, the detection limits are 0.03 μg/L for Cd(II), 0.05 μg/L for Pb(II) and Cu(II), which are about an order of magnitude lower than other reported recently. The peak current also exhibits well linear response over a concentration range from 0.5 to 50 μg/L.