China taps solar tech to extract hypersonic fuel ingredient from sea

Chinese researchers at Northwest A&F University have developed a novel solar-driven technology that simultaneously produces freshwater and extracts boron from seawater, addressing critical challenges in resource security and sustainable desalination. The method employs a specially engineered composite gel called MMS, composed of sodium alginate, MXene (a photothermal nanomaterial), and magnesium oxide (MgO), which captures boron ions while facilitating water evaporation. This gel floats at the air-water interface, using sunlight to heat the MXene layer and drive evaporation, while the MgO component adsorbs boron ions from the seawater. Laboratory tests demonstrated an evaporation rate of 2.14 kg/m²/hour and boron accumulation of 225.52 mg over nine hours, with the gel maintaining over 86% boron adsorption efficiency after seven reuse cycles. Field trials in Hong Kong confirmed the system’s practical potential, producing 5.20 kg of freshwater per square meter and extracting 122.45 mg of boron per square