A team lead by Prof. Wu Zhengyan and Prof. Zhang Jia from the Institute of Intelligence, Hefei institutes of physical science of Chinese Academy of Sciences, in collaboration with Prof. Cai Dongqing from Donghua University, constructed a new primary battery system that can effectively remove Cd2+ from the environment and generate electricity at the same time.

In paper published in Fundamental Research recently, the team described how they applied zinc as the anode, graphite as the cathode, and Cd2+-contaminated media (Cd2+-contaminated water or soil) as the electrolyte to develop this system.

Cd2+, with high solubility and migration rate, causes severe problems in ecosystems and human health. Although the traditional technologies can remediate Cd2+-contaminated water and soil, their practical application may be largely constrained by the high energy consumption and operation complexity. Therefore, there is an urgent need to develop new remediation technologies on Cd2+-contaminated media.

The battery system achieved efficient solidification and removal of Cd2+ in water and soil through the reduction of dissolved oxygen by internal Galvanic reactions in the battery. A large amount of OH was generated and precipitated with Cd2+ driven by an electric field.

They designed an output power supply through connection of multiple primary battery systems in series. In the process of Cd2+ removal, LEDs were continuously lit.

"The idea is to kill two birds with one stone," said Chen Chaowen, the first author of the paper.

They also checked plants, zebrafish, and soil microorganisms after applying this system and found they were all healthy.

The technology shows characteristics of low cost, green energy conservation, and simple operation, possessing broad application prospects.