A high-performing single-stage invert-structured solar water purifier through enhanced absorption and condensation

Interfacial solar vapor generation is an emerging technology for producing purified water with a minimized carbon footprint. While the evaporation rate has been significantly increased, the rate of water collection has been limited because of ineffective heat transfer during condensation and compromised light absorption in the conventionally designed solar still. In this work, an invert-structured, single-stage solar water purifier (ISWP) is elaborately designed and fabricated and consists of a top selective absorber and a honeycombed bottom water condenser based on hydrophobic nanostructured copper. This inverted structure not only avoids optical loss due to the vapor condensation but also realizes enhanced heat transfer and condensation. As a result, it can achieve a high water-collection rate of 1.063 kg m(-2) h(-1) and an overall efficiency of solar collected water of similar to 70% for single-stage solar purification systems.