A primary battery for efficient cadmium contamination remediation and electricity generation

In this work,two kinds of primary batteries,both of which included a Zn anode,C rod cathode,copper wire and electrolyte composed of Cd^(2+)-contaminated water or soil,were constructed in the first attempt to both remove Cd^(2+)and generate electricity.Unlike traditional technologies such as electrokinetic remediation with high energy consumption,this technology could realize Cd^(2+)migration to aggregation and solidification and generate energy at the same time through simultaneous galvanic reactions.The passive surface of Zn and C was proven via electrochemical measurements to be porous to maintain the relatively active galvanic reactions for continuous Cd^(2+)precipitation.Cd^(2+)RE(removal efficiency)and electricity generation were investigated under different conditions,based on which two empirical models were established to predict them successfully.In soil,KCl was added to desorb Cd^(2+) from soil colloids to promote Cd^(2+) removal.These systems were also proven to remove Cd^(2+) efficiently when their effects on plants,zebrafish,and the soil bacterial community were tested.LEDs could be lit for days by utilizing the electricity produced herein.This work provides a novel,green,and low-cost route to remediate Cd^(2+) contamination and generate electricity simultaneously,which is of extensive practical significance in the environmental and energy fields.