The UAE has abundant solar energy source with an average radiation of 6.3 kWh/m2 per day. Solar steam generation is emerging as a promising technology for its potential in harvesting solar energy for various applications such as power generation, water treatment, desalination, and sterilization. Inspired by the natural desalination process of halophytes of the UAE, different from energy intensive RO/thermal desalination, we propose an all‐in-one multifunctional 3D printed passive solar distillation device.
The capability of grey mangroves (Avicennia marina), the only species present in the UAE to repel 60‐80% salt in roots, and unexplored mechanism of seawater propagation in Salicornia (S. bigelovii), motivate us to understand the morphological microstructures and quantify the role of each part of plant towards natural passive desalination. Recent advances in micro 3D printing enable us to print artificial leaves, stems, and roots at a very high resolution comparable to the microstructures of halophytes. These 3D printed artificial leaves, stems, and roots, with controlled surface chemistry and microstructures, empower us to perform mechanistic study systematically. This also leads us to design synthetic plants with high‐performance solar thermal energy conversion efficiency, owing to the insightful understanding of the phenomena: (i) sunlight harvesting of absorber surface like leaves; (ii) liquid propagation in superhydrophilic hierarchical microchannels as in stem; and (iii) salt repelling microchannels as in roots; ultimately leading towards vapor condensation and freshwater collection.
The proposed approach is valuable to both large‐scale distillation and portable applications in rural areas or off‐grid islands. The ability to generate vapor and collect fresh water under ambient sunlight passively holds promise for significant cost reduction of existing solar thermal systems while opening up new applications such as desalination, wastewater treatment, and sterilization. The scope of the proposed work is well aligned with one of the strategic research categories of AARE: energy, water, and environment.