Solar-powered atmospheric water harvesting (AWH) with metal–organic frameworks (MOFs) has been recognized as an attractive way to alleviate water shortage stress in rural arid areas given the naturally abundant solar energy. However, the existing solar-powered AWH technologies only allow a singular water production mode: either solar heating-driven AWH which usually results in rather poor water productivity due to the limited availability of sufficient sunlight or conductive heating-driven all-day AWH with significantly improved water productivity but requiring additional electricity provided with a photovoltaic module. This greatly limits the flexibility in managing AWH based on climate conditions, water productivity, and energy cost. Herein, a sandwich-structured MOF monolith (denoted as CACS) with dual heating capacity, localized solar heating (LSH) and electrical heating (LEH), is presented. Compared with LSH, the use of LEH leads to more rapid and uniform heating of CACS monoliths, thereby driving a significantly enhanced water desorption efficiency with faster kinetics. Using the CACS monolith as an AWH sorbent, a new type of atmospheric water harvester is developed and able to produce water in multiple working modes: LSH-, LEH-, and LSH-/LEH-driven AWH, thereby enabling flexible AWH on demand: direct use of sunlight for LSH-driven AWH during the sunlight-sufficient day and/or LEH-driven all-day AWH powered by a photovoltaic module particularly during the sunlight-absent/-insufficient time (night or cloudy day). When working at the LSH-/LEH-driven AWH mode, the resulting prototype delivers 1.4 LH2O kgMOF –1 day–1 of water productivity with 2.3 kW·h L–1 H2O of energy consumption, corresponding to 5.4 times higher water productivity than the LSH-driven AWH working mode alone and 17.9% of energy saving at the cost of 22.2% of water productivity reduction compared with the LEH-driven AWH working mode alone. The current work, therefore, demonstrates a novel solar-powered AWH strategy that enables all-day water production with flexible choices on AWH working modes in terms of climate conditions, desired water productivity, and energy cost.

Atmospheric water harvesting (AWH) with metal−organic frameworks (MOFs) represents an attractive way to alleviate water shortage stress in arid regions. However, scaling up such a concept has been partially limited by the insufficient development of the highly efficient heating and suitable processing of MOF sorbents for making them more applicable to AWH devices. To overcome these limitations, a commercial carbon fiber (CF) bundle is embedded into an Alfumarate MOF monolith assisted by a cross-linked sodium alginate (SA) network, resulting in a cylindrical CF/Al-fumarate/SA (CAS) monolith with a coaxial structure. On applying electrical power, the embedded CFs could rapidly generate enormous localized electrical heating (LEH) within a CAS matrix with exceptionally high electrothermal conversion efficiency, thereby triggering the adsorbed water in CASs to be highly efficiently released in an energy-efficient way.In particular, such CAS monoliths can be easily connected to each other in either series or parallel, forming versatile CAS assemblies with well-controlled LEH capacity. Using a serial CAS assembly as atmospheric water sorbents, a newly atmospheric water harvester has been further developed based on an LEH-driven water desorption method. The resulting prototype enables to continuously work for 7.2 water harvesting cycles per day and deliver 1.7 and 1.2 L H2O kg Al-Fum/SA −1 daily water productivity under controlled indoor and outdoor conditions, corresponding to 4.4 and 6.2 kW•h L H2O −1 energy consumption, respectively. Please note that this is the first exploration in the use of flexibly assemblable MOF monoliths and the LEH-driven water desorption method for water production with AWH, demonstrating a promising way to achieve energyefficient, scalable, low-cost, and industrially favorable AWH in arid areas.

Sorption‐based atmospheric water harvesting (AWH) offers a promising solution to the water scarcity in arid regions. However, majority of the existing AWH sorbents are suffering from rather poor water productivity due to their slow water adsorption–desorption cycling capability especially when they are applied in high packing thickness. Herein, an oxygen plasma‐treated magnetic flower‐like porous carbon (P‐MFPC) with large open surfaces, abundant surface oxygen‐containing moieties, and excellent localized magnetic induction heating (LMIH) capacity is developed. These merits, together with the use of air‐blowing‐assisted water adsorption and LMIH‐driven water desorption strategy, synergistically allow P‐MFPC with 2 cm of packing thickness to complete a AWH cycling in 20 min and deliver a record 4.5 L H2O kg −1 day −1 of water productivity at 30% relative humidity. Synergistically enabling such an ultrafast AWH cycling at high sorbent packing thickness provides a promising way for the scalable high‐yield AWH with compact AWH systems.