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Developing highly efficient and multifunctional membranes toward oil adsorption and oil/water separation is of significance in oily wastewater treatment. Herein, a novel electrospun composite membrane with dual-scaled porous structure and nanoraised structure on each fiber was fabricated through electrospinning using biodegradable polylactide (PLA) and magnetic γ-Fe2O3 nanoparticles. The PLA/γ-Fe2O3 composite membranes show high porosity (>90%), superhydrophobic and superlipophilic performances with CH2I2 contact angle of 0°, good water adhesion ability like water droplets on a petal surface, excellent anti-icing performance, and good mechanical properties with a tensile strength of 1.31 MPa and a tensile modulus of 11.65 MPa. The superlipophilicity and dual-scaled porous structure endow the composite membranes with ultrahigh oil adsorption capacity up to 268.6 g/g toward motor oil. Furthermore, the composite membranes also show high oil permeation flux up to 2925 L/m2 h under the force of gravity. Even for oil/water emulsion, the composite membranes have high separation efficiency. We expect that the PLA/γ-Fe2O3 composite membranes can be used in oily wastewater treatment under various conditions through one-off adsorption or continuous oil/water separation, especially under low environmental temperature condition.

A new framework of reduced graphene oxide and boron nitride was constructed on the template of melamine foam. Its composite phase change materials exhibit excellent performances and can be applied in energy conversion and microelectronic device.

Helical carbon nanotube (HCNT) is a vital member of carbon nanomaterials, but little effort was devoted to explore its unique characteristics and applications during the past few decades. Here, we report an organic thermoelectric composite with an excellent photothermoelectric (PTE) effect by conformally wrapping polypyrrole (PPy) on the intricate surface of HCNTs, which have been confirmed to have remarkable near-infrared (NIR) photothermal conversion capability and ultralow heat transportation characteristics. The results indicate that with the increasing HCNT content, PPy shell thickness reduces and exhibits denser as well as partial orientation, while the inter-ring angle slowly decreases and the bipolaron becomes dominant in carrier composition gradually. Consequently, the Seebeck coefficient increases monotonically, whereas the electrical conductivity remains nearly invariant. The final composite combines the benign thermoelectric properties, excellent photothermal response performance, and the lowest thermal conductivity of the carbon-based thermoelectric composite yet reported (0.064 W m −1 K −1 ). A single strip NIR light-stimulated adjustable delay switch was designed and fabricated, with the open-circuit voltage and short-circuit current under a 400 mW cm −2 NIR-stimulated approach to 720 μV and 62 nA with the discrepancy of consecutive periodic output signals less than 4.2%, exhibiting incredible stability and reliability and demonstrating the highest output voltage of a single strip among the reported organic PTE composite at room temperature. Our work fills in a gap of HCNT research, which hitherto existed in the PTE and thermoelectric field.