One-step solvothermal synthesis of MoS2@Ti cathode for electrochemical reduction of Hg2+ and predicting BP neural network model

Abstract

Although mercury is one of the heavy metal pollutants that endanger human health and the environment, it is also an essential raw material needed for industrial development. We try to use electrochemical reduction method to realize the resource utilization of mercury. MoS2@Ti electrodes were prepared using a one-step solvothermal method, and XRD, XPS, SEM and EDS were used to analyze the MoS2 powder. The prepared highly reactive MoS2@Ti electrode was used as a cathode to electrochemically reduce the mercury-containing solution. After a series of single-factor experiments, under the conditions of stirring rate of 400 r/min, electrode spacing of 20 mm, constant potential of 2 V and electrolytic time of 2 h, the removal efficiency of Hg2+ in 10 ∼ 50 mg/L HgSO4-10 % H2SO4 solution reached 94.5 % or above. The reaction mechanism of MoS2@Ti was investigated mainly by using the indirect reaction of superoxide radicals and hydrogen radicals to achieve the reduction of Hg2+. And the MoS2@Ti electrode can still reach 80.0 % removal efficiency after five times of repeated use. A neural network model was used to predict the efficiency of Hg2+ reduction in this system with a high accuracy of RMSE 1.3049 and R2 0.9511. The above study contributes to the realization of the resource utilization of mercury.