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The emerging solar desalination technology has incomparable advantages for providing a clean water solution. However, the issue of salt accumulation on the solar evaporator tops during the steam generation leads to a considerable decrease in the evaporation rate. Herein, we demonstrate a superhydrophobic/superhydrophilic Janus evaporator that enables a stable solar evaporation even in saturated brine. Our Janus solar evaporator with a superhydrophobic top and a superhydrophilic bottom has been manufactured integrally, allowing for a fast steam evaporation without the impediment of the accumulated salt residues. The superhydrophobic top changes the water passageway from the center toward the edges while it allows for the vertical transport of both solar thermo and evaporated steams. Salt residues would only be deposited at the edges of the superhydrophilic bottom, allowing for a long-term stability of the evaporator for a continuous (>50 h) solar evaporation in saturated brine, which is record-breaking for salt-resistant solar evaporators. With stable and efficient evaporation performance out of high-salinity brine, this work provides a fascinating avenue for the desalination of seawater in a salt-resistant and efficient manner.

Magnetic soft materials (MSMs) have a rising requirement in self-powered stress sensors and energy harvesters due to the considerable flexibility and force-driven variable magnetic strengths. Structural designs aided by additive manufacturing for MSMs can regulate their mechanoelectrical conversion capability. Here we report that porous MSMs with negative, zero and positive Poisson’s ratios (NPR, ZRP and PPR, respectively) composed of Nd2Fe14B and thermoplastic urethane can be one-step fabricated by selective laser sintering. The mechanoelectrical conversion performances of MSMs with three different kinds of Poisson’s ratios are investigated under vertical deformations. The results show that the lateral contraction of NPR MSMs concentrates the magnetic field distribution, leading to the maximum electrical output (7.42 mV at the strain of 40 % and compression velocity of 40 mm/s), which is 1.80 and 2.07 times that of ZPR and PPR MSMs, respectively. The experimental results have been confirmed by finite element analysis including ABAQUS/CAE and Ansys Maxwell. In addition, the electrical output of as-printed magnetoelectric devices can be adjusted by altering cells’ parameters and their array permutations. In summary, the study for improving the electrical outputs of MSMs by structural design will offer a high-efficiency and promising route for self-powered sensors and other mechanoelectrical conversion devices.