Xuemei Zhang

Solar intermittency limits the continuous operation of solar-driven interfacial evaporation (SDIE) systems. While integrating phase-change materials (PCMs) like polyethylene glycol (PEG) provides passive thermal buffering, the physical leakage of molten PEG severely compromises long-term evaporator stability. To resolve this bottleneck, this study introduces a shape-stabilized bilayer phase-change evaporator using waste three-dimensional polyurethane (PU) sponges. Through cyclic alternating immersion, PVA and PEG are anchored within the scaffold, followed by coating a carbon nanotube photothermal layer. Crucially, abundant hydroxyl groups on the PVA chains securely confine and fix the PEG molecules via strong intermolecular interactions. This robust network anchors the molten PEG, granting exceptional form-stability without obstructing the hierarchical pores required for continuous capillary water transport. Evaluating different PEG molecular weights demonstrated that longer chains enhance crystallinity, phase-change enthalpy, and anti-leakage capacity. The optimized S-1500 composite balances thermal storage and conductivity, achieving a 1.31 kg·m⁻²·h⁻¹ evaporation rate and 73.0% efficiency under 1 sun. Its dynamic latent heat release sustains a robust 0.92 kg·m⁻²·h⁻¹ dark evaporation rate. Furthermore, the hydrophilic network enables rapid ion back-diffusion, ensuring 12-hour stable, salt-free operation in highly concentrated NaCl (20 wt%). These findings establish a reliable pathway for durable, all-weather solar desalination.

Flexible strain sensors face a fundamental trade-off between sensitivity and sensing range. Furthermore, the interfacial modulus mismatch induced by traditional multi-step fabrication often leads to delamination under complex operating conditions. Inspired by the hierarchical skin morphology of crocodile flanks, we report a one-step regional spraying method to fabricate a superhydrophobic sensor. Driven by a strain-stiffness mismatch, this sensor features a dual-domain hierarchical parallel wrinkled structure, consisting of a polydimethylsiloxane/carbon nanotubes (PDMS/CNTs) composite integrated onto a flexible latex substrate. By differentially modulating the microscopic conductive spacing, this structure achieves an exceptional hierarchical electromechanical response. Specifically, the dense wrinkles in the thin regions act as "strain amplifiers," inducing the rupture of percolation pathways under minute deformations. Conversely, the broad and sparse wrinkles in the thick regions function as "geometric strain buffers," maintaining the connectivity of the conductive network under large strains through geometric unfolding. Moreover, the in-situ induced wrinkles construct a stable Cassie-Baxter superhydrophobic barrier. This integrated "structure-interface-function" design effectively resolves the sensitivity-sensing range trade-off, delivering a high gauge factor (GF) of 7825.3 alongside a broad sensing range of 212%. The sensor additionally exhibits a low detection limit (0.5%), low hysteresis (4.82% at an extreme strain of 200%), and a rapid response time (180 ms). Crucially, the sensor maintains stable electrical and interfacial performance even after 20,000 s of dynamic fatigue testing, immersion in highly corrosive environments, and continuous fluid scouring. Integrated with machine learning clustering algorithms, the proposed sensor exhibits promising potential for intelligent interaction and advanced engineering applications across complex scenarios, including multidimensional physiological monitoring, underwater robotic perception, and tactile object recognition for smart grippers.

The development of coal–water slurry (CWS), a new type of coal-based chemical product in China, has garnered increasing attention as a potential substitute for petroleum resources. The Coriolis mass flow meter is widely used in industrial measurement due to its low uncertainty and its ability to simultaneously measure fluid density and mass flow rate, with a single-phase measurement error as low as 0.1%. However, significant errors still exist in multiphase flow measurement scenarios. To address this issue, we designed and constructed a CWS liquid–solid two-phase flow measurement platform to investigate the flow measurement errors of CWS in Coriolis mass flow meters under various conditions. A deep learning correction framework was developed to mitigate the significant measurement errors in liquid–solid two-phase flow. Based on the theoretical support provided by repeatability experiments, two correction models were established: (1) An error correction model based on a BP neural network was developed, which provided corrections for the measurement errors of CWS liquid–solid two-phase flow. The first correction results showed that the corrected error of the predictive model was 3.98%, a significant improvement compared to the 5.11% error measured by the X company’s meter. (2) Building on this, a second correction model was established through algorithm optimization, successfully reducing the corrected error of the predictive model to 1.01%. Through this study, we aim at providing a new technical approach for Coriolis mass flow meters in the field of liquid–solid two-phase flow measurement, enhancing measurement accuracy, reducing costs, and offering more reliable data support for industrial process control and scientific research.

The pollution of water by oil is a global challenge. In this study, the design and fabrication of a superhydrophobic stainless steel mesh are reported. This was achieved through a sample “glue + fly ash” fabrication method. The fly ash was first modified by a stearic acid solution impregnation method. After the modification, the fly ash was then bonded to the surface of a stainless-steel mesh by an epoxy resin solution to obtain the superhydrophobic mesh. The introduction to the modified fly ash endows the mesh with excellent corrosion resistance and superhydrophobicity when compared with the original mesh. The as-prepared mesh could separate various oil and organic solvents from water with a separation efficiency exceeding 98%. Interestingly, the oil separation capacity of the as-prepared mesh still kept a high value after 30 cycles of reuse. The simplicity, eco-friendliness and low cost of this method turn it into a practical and realistic approach to the large-scale fabrication of superhydrophobic surfaces. These properties make the as-prepared mesh an ideal candidate for actual oily wastewater treatment. Graphical Abstract

Magnetically driven superhydrophobic materials were coated on the surface of polyurethane sponges by Fe₃O₄ nanoparticals and stearic acid. The as-prepared sponge was characterized by scanning electron microscope, fourier transform infrared spectroscopy and other analytical techniques. The surface wettability of the as-prepared sponge, the separation capacity of oil/water mixtures and emulsions, the sorption kinetics of different types of oil, and the recyclability of the materials were studied. The Fe₃O₄ and stearic acid were coated onto the skeleton surface of the sponge, which make the as-prepared sponge possess magnetic and hierarchically microstructure. The water contact angle reach up to 158° on the surface of the superhydrophobic sponge. The materials also shows highly efficient oil/water mixtures and emulsions separation. Moreover, the oil separation capacities still keep a high value after 50 cycles of squeezing the saturated absorbed as-prepared sponge. All of these satisfactory properties made the as-prepared sponge as an ideal absorbents for oil/water mixtures and emulsions separation in the future.

The superhydrophobic magnetic sponge were prepared by Fe 3 O 4 nanoparticals and stearic acid which were coated on the surface of polyurethane sponge. The preparation process of the superhydrophobic materials are prepared under mild, low-cost and environment-friendly conditions. pieces of PU sponges were decorated immersed in a ethanol solution which uniform suspension Fe 3 O 4 nanoparticles ethanol by ultrasonication ,and the obtained PU sponges were modified with stearic acid. The Fe 3 O 4 and stearic acid were coated onto the skeleton surface of the sponge, which make the as-prepared sponge possess magnetic and hierarchically microstructure. The high elasticity sponge can through the simple squeeze realize oil recovery. After 5 cycles, the as-prepared sponge retains excellent absorption properties. The superhydrophobic magnetic polyurethane sponge has great potential in industrial oil separation and oil spill recovery in future.