Over 10 kg m−2 h−1 Evaporation Rate Enabled by a 3D Interconnected Porous Carbon Foam

• Published in: Joule Vol. 4; no. 4; pp. 928 - 937
• Main Authors: Li, Jinlei, Wang, Xueyang, Lin, Zhenhui, Xu, Ning, Li, Xiuqiang, Liang, Jie, Zhao, Wei, Lin, Renxing, Zhu, Bin, Liu, Guoliang, Zhou, Lin, Zhu, Shining, Zhu, Jia
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 15.04.2020
• Subjects: 3D interconnected carbon foam; convective flow; high evaporation rate; porous evaporator; solar evaporation; vapor diffusion; wastewater treatment; high evaporation rate; solar evaporation; convective flow; wastewater treatment; 3D interconnected carbon foam; porous evaporator; vapor diffusion
• ISSN: 2542-4351; 2542-4351
• DOI: 10.1016/j.joule.2020.02.014

The recent advancements in evaporating water using renewable energy provide one of the promising pathways for treating water with minimized carbon footprint. Pursuing a high evaporation rate of water has been the central focus of this field, as it is directly related to the throughput of evaporative water treatment. However, in conventional designs of evaporators, diffusion of vapor into the atmospheric environment has been the limiting step for evaporation. In this work, we demonstrate that a carbon foam with a three-dimensional interconnected porous structure enables sufficient diffusion of vapor with a convective flow and therefore realizes an evaporation rate as high as 10.9 kg m−2 h−1 and outdoor evaporation of 42.0 kg m−2 for continuous 13 h. With such a high evaporation rate achieved, it shows great promise toward a high-throughput, around-the-clock, and eco-friendly technology of evaporative wastewater disposal. [Display omitted] •A porous evaporator is tailored for effective phase transition and vapor diffusion•Unique gas-assisted expansion and perforation is developed for the evaporator•An evaporation rate of 10.9 kg m−2 h−1 is realized under 1 sun with a convective flow•High evaporation rate can be maintained day and night Recently, evaporative water treatment driven by renewable energy is emerging as one of most promising approaches to address the growing water shortage with minimized carbon footprint. Pursuing a high evaporation rate is the central focus of this domain. Past advancements mainly rely on promoting the phase transition from water to vapor via tailoring structures at nano and/or microscale. In this work, we reveal that it is crucial to promote vapor diffusion to the environment. A three-dimensional (3D) interconnected porous carbon foam is designed to realize an evaporation rate as high as 10.9 kg m−2 h−1 under 1-sun illumination coupled with a natural convective flow. It is expected that the strategy reported here could open up a new path for developing high-throughput evaporative water treatment. A three-dimensional (3D) interconnected porous carbon foam was developed. It is capable of not only effective phase transition but also vapor diffusion assisted by a convective flow. Therefore, evaporation rate as high as 10.9 kg m−2 h−1 is realized, which is highly desirable for evaporative water treatment technology.