Vertically Aligned Graphene Sheets Membrane for Highly Efficient Solar Thermal Generation of Clean Water

Abstract

Efficient utilization of solar energy for clean water is an attractive, renewable, and environment friendly way to solve the long-standing water crisis. For this task, we prepared the long-range vertically aligned graphene sheets membrane (VA-GSM) as the highly efficient solar thermal converter for generation of clean water. The VA-GSM was prepared by the antifreeze-assisted freezing technique we developed, which possessed the run-through channels facilitating the water transport, high light absorption capacity for excellent photothermal transduction, and the extraordinary stability in rigorous conditions. As a result, VA-GSM has achieved average water evaporation rates of 1.62 and 6.25 kg m h under 1 and 4 sun illumination with a superb solar thermal conversion efficiency of up to 86.5% and 94.2%, respectively, better than that of most carbon materials reported previously, which can efficiently produce the clean water from seawater, common wastewater, and even concentrated acid and/or alkali solutions.

Design of 3D Graphene‐Oxide Spheres and Their Derived Hierarchical Porous Structures for High Performance Supercapacitors

“…In this case, the ice only grows gradually from outside interface to inside, during which the layers tend to concentrate at the boundary of ice crystals and align vertically. [60,61] In order to obtain a homogeneous 3D assembly, the GO dispersion should be congruently frozen. Thus, the volume of the dispersion must be minimized.…”

Novel Receiver-Enhanced Solar Vapor Generation: Review and Perspectives

“…Later on, polypyrrole-deposited stainless steel mesh [119], airlaid-paper-based Au nanoparticle film [120], and bilayered hybrid biofoam composed of bacterial nanocellulose and reduced graphene oxide [108,113] were also used for solar desalination. Another interesting and innovative example was vertically aligned graphene sheets membrane (Figure 14d-f) [114]. The …”

“…(e,f) Solar thermal conversion efficiency and measured concentrations of five primary ions in an actual seawater sample before and after purification using vertically aligned graphene membranes. Reprinted with permission from [114]. Copyright (2016) by American Chemical Society.…”

“…The purple (green) shaded area refers to the overall typical salinity achieved by traditional membrane (distillation) desalination process, respectively. (d) SEM cross sectional image of vertically aligned graphene membranes inset image shows the schematics water transport behavior [114]. (e,f) Solar thermal conversion efficiency and measured concentrations of five primary ions in an actual seawater sample before and after purification using vertically aligned graphene membranes.…”

More carbon and less salt

“…Another interesting approach is the use of graphene oxide materials to enhance absorption in solar desalination, as reported by Jia Zhu and co-workers 1,2 and more recently by Liangti Qu and co-authors 3 , which could result in the development of portable water treatment devices.…”