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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.

To improve the inherent properties of polylactic acid (PLA), cellulose nanocrystals (CNCs) have been picked up as the nanofillers. However, the hydrophilic CNCs show poor compatibility with hydrophobic PLA, which usually fails to improve the performance of PLA. Inspired by mussel, polydopamine (PDA) decorated CNCs (PDA@CNCs) were utilized as nanofillers for PLA modification. With the introduction of PDA grafting on the surface of CNCs, the compatibility of CNCs in the PLA matrix was improved. The PDA acts as the bridge to enhance the interfacial adhesion between CNCs and PLA, improving the mechanical properties of the composite. At low addition level (1 wt%), the obtained composites (PDA@CNCs/PLA) showed enhanced mechanical properties 17.31% and 33.01% increases for tensile strength and elongation at break, respectively. In addition, the existence of PDA with UV radiation absorption performance induces PDA@CNCs/PLA UV-shielding property, which could undoubtedly extend the cycle time of the product and has the potential to be used in packaging for light-sensitive foods, pharmaceuticals, etc. The mussel-inspired PDA decoration of CNCs by this work provided a new strategy for the enhancement of the inherent properties of PLA.

Tuning and controlling the plasmon coupling of noble metal nanoparticles are significant for enhancing their near-field and far-field responses. In this work, a novel heterogeneous plasmonic assembly with a controllable hot spot model was proposed by the conjugation of Au nanospheres (NSs) and Au@Ag core–shell nanocube (NC) films. Three hotspot configurations including point-to-point type, point-to-facet type, and facet-to-facet type were fabricated and transformed simply by adjusting the doping ratio of nanoparticles in the co-assembly film. Expectedly, the localized surface plasmon resonance (LSPR) property and surface-enhanced Raman scattering (SERS) performance of the binary assembly film exhibit distinct diversity due to the change in the hotspot conformation. Interestingly, the point-to-facet hotspot in hybrid assembly films can provide the most extraordinary enhancement for SERS behavior compared with single-component Au NS and Au@Ag NC plasmonic assemblies, which is further confirmed by the finite-different time-domain simulation results of dimer nanostructures. In addition, the two-dimensional binary assemblies of Au NS doping in Au@Ag NCs with excellent sensitivity and high reproducibility were successfully applied in the identification of ketamine. This work opens a new avenue toward the fabrication of plasmonic metal materials with collective LSPR properties and sensitive SERS behavior.

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.

Inspired by marine mussels, dopamine with a catechol structure was self-polymerized in a weak alkaline environment and deposited on the surface of wood fiber (WF) to enhance the interface between WF and polylactic acid (PLA). At the same time, silver nanoparticles (Ag NPs) were attached to the surface of WF under the reducibility of polydopamine (PDA), giving the composite antibacterial activity against Aspergillus niger. The results showed that PDA and Ag NPs were successfully generated and attached to the WF surface. The thermal stability of WF was improved after the modification, which the maximum decomposition rate temperature of WF/PDA/Ag was increased by 29.2°C compared with WF. According to relevant analysis, the tensile properties of WF/PDA-PLA were significantly improved. Compared with PLA, the tensile strength and Young's modulus of WF/PDA-PLA were increased by 8.13% and 52.89%. The bacteriostatic circle method measurement showed WF/PDA/Ag-PLA had a particular antibacterial ability for Aspergillus niger.