A Moisture‐Hungry Copper Complex Harvesting Air Moisture for Potable Water and Autonomous Urban Agriculture

Abstract

The earth's atmosphere houses an enormous amount of water, which could be effectively exploited for a plethora of applications. While the development of materials for harnessing this abundant resource has gained impetus in recent years, limited efforts have been devoted to in‐depth research on their agricultural applications. Herein, a novel copper(II)–ethanolamine complex (Cu‐complex), which has a maximum water uptake of up to 300% and a water production rate of 2.24 g g−1 h−1 under natural sunlight, is reported. As a proof‐of‐concept application, using this material, a fully automated and self‐sustainable solar‐powered SmartFarm device is developed. The Cu‐complex harvests atmospheric water during the night, stores the adsorbed water within, and efficiently releases the adsorbed water during the day when the device is exposed to sunlight. The water harvesting and irrigation process can be fine‐tuned to suit different types of plants and local climates for an optimal cultivation. With the SmartFarm in operation, the demand for freshwater for irrigation could be greatly reduced and urban farming techniques such as large‐scale rooftop farming could be promoted with a view of alleviating both water and food scarcity in the near future.

Photothermal Devices for Sustainable Uses Beyond Desalination

“…[ 102 ] Recently, Yang et al reported a complex of CuCl 2 and ethanolamine with excellent hygroscopicity. [ 21 ] Coupling with the photothermal agent such graphene, CNT, or carbon black, a photothermal humidification/dehumidification system was constructed for solar‐powered smart farms.…”

“…[20] Combined with hygroscopic materials, the photothermal evaporator can capture moisture from the environment and produce clean water through a condensation-evaporation cycle. [21] Moreover, the latent heat, [22] temperature or salt concentration gradient, [10,23] as well as the water flow during evaporation, can drive an energy-generation process along with desalination, acquiring both freshwater and electricity simultaneously.…”

Ultrahigh solar-driven atmospheric water production enabled by scalable rapid-cycling water harvester with vertically aligned nanocomposite sorbent

“…8 The working performance of SAWH system is strongly dependent on the water sorption capacity of sorbents; however, traditional porous sorbents (e.g., silica gels and zeolites) provide low water productivity because of their poor water sorption performance at low RH. 9 Therefore, many novel sorbents such as metal-organic frameworks (MOFs), [10][11][12][13][14] hydrogels, [15][16][17] liquid solutions, 18,19 and composite sorbents 20,21 with extraordinary performance were designed and exploited by the efforts from materials scientists in past years. Lately, these novel sorbents with high water sorption performance and special thermal/electrical effects also inspired energy-related applications such as energy storage, 22,23 thermal management, [24][25][26][27] electricity/fuel generations, 28,29 or co-application.…”

“…The recently reported hydrogels not only present high-water capture capacity but also have many other desirable superiorities of thermo-response, 15,[38][39][40] fast sorption-desorption kinetics, 41 and low-cost, showing a promising application in the agricultural irrigation. 21,42 In comparison with above state-of-art sorbents, the hygroscopic sorbents of lithium chloride (LiCl), calcium chloride (CaCl 2 ), and ion solutions have strong competitiveness for SAWH at arid regions due to their higher water uptake at low RH. In our previous work, we elaborated the multi-step water sorption mechanism of hygroscopic salts that integrating the chemisorption, deliquescence, and solution absorption processes, obtaining a high-water uptake at low RH.…”

Wood‐Derived Systems for Sustainable Oil/Water Separation

“…[1] Separating oil and water is currently a global challenge. [2][3][4][5][6][7][8][9][10][11][12][13][14] Thus, more effort is required for the construction of effective systems based on functional materials, devices, and techniques that facilitate the sustainable separation of oil/ water mixtures (O/W-Ms) to obtain clean water and to enable the recycling of expensive oil. Water is often "polluted" by oil and forms oil/water layered mixtures (O/W-LMs), oil-in-water emulsions (O/W-Es), and water-in-oil emulsions (W/O-Es).…”