Efficient solar desalination using three-dimensional aluminum nanoparticles

Recently, Professor Zhu Jia and his research group at Nanjing University have made important progress in the research of efficient solar desalination materials. For the first time in the international community, Zhu Jia's research group has achieved high-efficiency solar water desalination using the metal nanoplasmon enhancement effect. The energy transfer efficiency is about 90%, and the salinity is reduced by 4 orders of magnitude before and after desalination.

The traditional seawater desalination device has the problems of large volume, high energy consumption, large carbon emission, and low desalination efficiency. Although seawater desalination technology using solar energy distillation is low-carbon and environmentally friendly, it is limited by the low light-to-heat conversion efficiency and cannot be applied on a large scale.

The researchers found that three-dimensional aluminum nanoparticle plasmon blackbody material is an excellent system for achieving high-efficiency solar desalination. The material has a super wide solar spectrum high light absorption efficiency, and the average absorption efficiency in the solar spectrum of 400 to 2500 nanometers is greater than 96%, which ensures the efficient use of solar energy in the seawater desalination process.

In practical work, this tightly-arranged metal nanoparticle film floats on the surface of seawater. The localized plasmon-enhanced effect of the nanoparticle causes the surface seawater at the membrane-liquid interface to rapidly warm up, producing freshwater vapor, and The porous structure provides an effective passage for steam escape. The measured water quality after desalinization is better than the World Health Organization’s standards for potable water.

At the same time, the preparation of nano-aluminum particles plasmonic blackbody film material uses low-cost metal aluminum as the only raw material, and adopts a simple and scalable production self-assembly preparation method, which is easy to popularize and apply.

The related results were published in the journal Nature-Photonics. The American magazine "Science" highly praised this work with the title "New water purification system can quench the thirst in the world." Experts said that this material is of great significance for the large-scale application of low-cost, high-efficiency solar desalination technology.