Magnetically Driven Tunable 3D Structured Fe₃O₄ Vertical Array for High‐Performance Solar Steam Generation

Abstract

Structural design of the solar‐absorbing layer has been considered as one of the most direct and effective approaches for improving the solar steam generation performance by maximizing the absorption of sunlight, but great challenges in manipulation simplification and structure controllability still remain. Herein, a polyester (PET) fabric covered with a vertically aligned 3D tower‐like ferrosoferric oxide (Fe3O4) array via a convenient magnetically driven spray‐coating method is reported, and both the spatial density and height of the Fe3O4 array are tunable upon spraying time. It shows an extremely high solar absorbance (98.6%) in the entire solar spectrum, which is superior to the corresponding 2D Fe3O4 structure (91.1%). Combining the obtained 3D Fe3O4/PET with a yolk‐shell hydrophobic/superhydrophilic modified melamine‐formaldehyde (mMF) sponge, the carefully designed and fabricated 3D Fe3O4/PET‐mMF evaporator can realize a high water evaporation rate of 1.59 kg m−2 h−1 under 1 kW m−2 solar illumination, outperforming most related solar steam generation systems. With the advantages of cost‐effectiveness, high evaporation rate, reliable endurance, and structural controllability, this 3D structural design provides an avenue to build up high‐performance solar energy‐driven water steam generation systems.

Stable and Salt-Resistant Janus Evaporator Based on Cellulose Composite Aerogels from Waste Cotton Fabric

“…Global freshwater scarcity has been considered a serious issue because of climate change and population growth. − Developing an efficient water purification technology is an urgent task to alleviate the water crisis. − Solar steam generation is considered as a promising solution to obtain clean water from seawater and waste water by using renewable solar energy. It has great industrial potential to alleviate water shortages. , A solar steam generator is generally composed of photothermal materials and substrates. Carbon-based materials are widely used in interfacial solar steam generation due to their photothermal conversion properties. , Furthermore, substrates play an important role in improving the solar energy conversion efficiency of water evaporation due to their direct impact on solar energy collection, water supply and storage, heat management, and steam transmission in the evaporator .…”

Fe3O4/Diatomite-Decorated Cotton Evaporator for Continuous Solar Steam Generation and Water Treatment

“…Generally, three-dimensional water channels often produce heat conduction with water bodies; therefore, using two-dimensional water channels based on fiber paper and one-dimensional water channels based on cotton can reduce heat loss [ 10 , 11 , 12 , 13 ]. To further reduce heat loss, a layer of insulating material, such as polyethylene foam, is placed between the photothermal conversion layer and the water to prevent the material from contacting the water, thereby preventing heat loss [ 14 , 15 , 16 , 17 , 18 , 19 , 20 ].…”

Towards highly salt-rejecting solar interfacial evaporation: Photothermal materials selection, structural designs, and energy management

“…The deformable structure helps it deeply study the influence of origami structure on evaporation performance. In addition, as a textile material, fabric has flexible and porous characteristics, and it is undoubtedly a feasible strategy to combine photothermal materials with fabric [101][102][103][104]. Using the flexibility and draping of fabric [101], the researchers have designed and developed an indirect-contact evaporation scheme by hanging a hydrophilic photothermal fabric in air and immersing two fabric edges in two seawater tanks.…”