Source: Chemical & Engineering News, 2/6/26
'Seawater has tons of lithium, but it is present at a concentration of just 200 parts per billion (ppb) and is drowned by sodium and other more abundant ions. Efficiently extracting lithium from the sea requires increasing its concentration and not nabbing sodium in the process.
Materials such as hydrogen manganese oxide (HMO) that selectively adsorb lithium are one solution, but they are slow. So researchers engineered a seesaw-like device based on HMO that boosts lithium concentrations by more than 15-fold in seawater (Device 2026, DOI: 10.1016/j.device.2025.101028). Using just sunlight and gravity, the device captures 70% more lithium than the adsorbent would on its own. And as it rocks back and forth, it casts off unwanted salts that build up on its surface.'
The research team consisted of Hao-Cheng Yang and Zhi-Kang Xu of Zhejiang University, Seth B. Darling of Argonne National Laboratory, and colleagues.