【Frontiers in HaiChuan Chemical Technology】Nanjing University of Technology proposes a new approach for lithium extraction from seawater by utilizing the ion separation properties of inorganic solid electrolytes

Thread Content

Nanjing Tech University proposes a new approach for lithium extraction from seawater. Recently, a team led by professors Xing Weihong and Zhong Zhaoxiang from Nanjing Tech University published a review article in Nature Reviews Materials, providing a comprehensive overview of inorganic solid-state electrolytes (ISSEs) and revealing the ion separation properties of these materials, thus offering new ideas for the design of efficient lithium-ion separation membranes. 　　Efficient and green seawater lithium extraction technology is regarded as a tough challenge in the scientific research community. In recent years, significant progress has been made in the development of membrane materials based on Er-level ion channels, but this technology still faces challenges such as insufficient stability, limitations in large-scale application, and a need for improved lithium selectivity. 　　“Compared to emerging ion separation membrane materials, ISSEs are an ideal choice for ion separation membranes due to their fast lithium ion transport and high ionic conductivity. ”Zhong Zhaoxiang explained. The crystal structure of ISSEs is at the core of their selective ion transport mechanism. Due to the limited lattice pores of ISSEs, which cannot accommodate lithium ions with a complete hydrated shell, these lithium ions must first shed their outer bound water molecules before passing through the material. After dehydration, bare ions traverse the lattice, jumping between interconnected vacancy and interstitial defects to form well-defined ion channels. “Ion channels function like ‘smart gates’: ions that match the lattice structure, such as lithium ions, can pass through smoothly, while those that do not match are excluded, thereby enabling selective ion transport. ” Zhong Zhaoxiang said. 　　Currently, the ISSEs independently developed by this team have been successfully applied in lithium extraction experiments using seawater and brine from salt lakes, yielding lithium products of high purity. In the future, ISSEs are expected to drive the large-scale development of green lithium resources, providing material support for new energy vehicles, high-end manufacturing, and the new energy industry.