Interfacial solar steam generation (ISSG) has emerged as a promising and eco-friendly desalination technology for producing fresh water from diverse sources, offering a sustainable solution to global water scarcity. However, practical applications face a significant bottleneck: as the evaporation surface area increases, the evaporation rate decreases, limiting large-scale implementation. In this study, a hydrogel evaporator with a donut-shaped structure is developed using 3D-printed molds to address this issue by enhancing thermal convection and reducing evaporation dead zones. Simulations reveal that optimized structural designs improve heat distribution and air convection, leading to a significant improvement in evaporation performance. Experimental results further confirm an impressive evaporation rate of 3.47 kg m −2 h −1 , representing a 66% improvement compared to conventional designs. This work highlights the potential of structural design in hydrogel evaporators to optimize thermal management and enhance evaporation efficiency. By achieving higher evaporation rates while minimizing material usage, this approach provides a scalable strategy for efficient solar desalination.
Xuechen Liang,Xinjie Zhang,Zhipeng Liu,Qichen Huang,Han Zhang,Changkun Liu,Yizhen Liu
Solar interfacial evaporation is a promising way to generate clean water from seawater using clean, abundant, and sustainable solar energy. However, non-directionally moving water with high thermal conductivity acts inevitably as a medium for heat transfer from the surface to the bottom through heat convection, resulting in low energy efficiency and a low evaporation rate. Herein, a gradient structured composite hydrogel combining a desired functional differentiation is reported. The network sizes in the hydrogel continuously change, demonstrating an enhanced capillary effect and a direction-limited water supply capability, inhibiting the heat convection loss. In addition, the reported gradient hydrogel shows broadband light absorption, satisfactory mechanical properties under a saturated swelling state, an unusually higher water evaporation rate for brine compared with that for pure water, and an inherent ability to evaporate under both 1 sun illumination and dark environment. The proposed gradient channels to restrict the flow direction of liquid, and consequently the heat convection loss, will have an significant impact on the design of other efficient photothermal evaporation systems and even the field of mass and heat transfer.
危险品化学品经营许可证（带存储）