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Oily wastewater and oil spills pose a threat to the environment and human health, and porous sponge materials are highly desired for oil/water separation. Herein, we design a new superhydrophobic/superoleophilic TiO 2 -decorated polyvinyl alcohol (PVA) sponge material for efficient oil/water separation. The TiO 2 –PVA sponge is obtained by firmly anchoring TiO 2 nanoparticles onto the skeleton surface of pristine PVA sponge via the cross-linking reactions between TiO 2 nanoparticles and H 3 BO 3 and KH550, followed by the chemical modification of 1 H ,1 H ,2 H ,2 H -perfluorodecyltrichlorosilane. The as-prepared TiO 2 –PVA sponge shows a high water contact angle of 157° (a sliding angle of 5.5°) and an oil contact angle of ∼0°, showing excellent superhydrophobicity and superoleophilicity. The TiO 2 –PVA sponge exhibits excellent chemical stability, thermal stability, and mechanical durability in terms of immersing it in the corrosive solutions and solvents, boiling it in water, and the sandpaper abrasion test. Moreover, the as-prepared TiO 2 –PVA sponge possesses excellent absorption capacity of oils or organic solvents ranging from 4.3 to 13.6 times its own weight. More importantly, the as-prepared TiO 2 –PVA sponge can separate carbon tetrachloride from the oil–water mixture with a separation efficiency of 97.8% with the aid of gravity and maintains a separation efficiency of 96.5% even after 15 cyclic oil/water separation processes. Therefore, the rationally designed superhydrophobic/superoleophilic TiO 2 –PVA sponge shows great potential in practical applications of dealing with oily wastewater and oil spills.

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A highly electronegative carboxyl-decorated anionic metal−organic framework (MOF), (Me 2 NH 2 ) 2 [In 2 (THBA) 2 ]-(CH 3 CN) 9 (H 2 O) 21 (InOF; H 4 THBA = [1,1′:4′,1″-terphenyl]-2′,3,3″,5,5′,5″-hexacarboxylic acid), with high-density electronegative functional sites was designed and constructed. One unit cell of InOF possesses 12 negative sites that originate from the negatively charged secondary building unit [In(COO) 4 ] − and exposed carboxyl groups on the ligand. The abundant electronegative sites can facilitate the hopping of ions in channels and thus result in highly efficient ion conductivities for various metal ions. Our results show that Li + -loaded materials have a remarkably high ion conductivity of 1.49 × 10 −3 S/cm, an ion transference number of 0.78, and a relatively low activation energy of 0.19 eV. The Na + , K + , and Zn 2+ ion conductivities of InOF are 7.97 × 10 −4 , 7.69 × 10 −4 , and 1.22 × 10 −3 S/cm at 25 °C, respectively.

Due to serious global warming and environmental issues, the demand for clean and sustainable energy storage devices is significantly increased. Often accompanied by rapid growth of portable electronic vehicles and devices, massive electromagnetic wave pollution becomes unavoidable. To mitigate the above two issues, this mini-review summaries preparation methods and recent developments of MXene/polyaniline-based composites for their applications in electrochemical devices and electromagnetic interference shielding. Based on excellent synergistic effects between single compounds and designed hierarchical structures, MXene/polyaniline-based composites usually exhibit enhanced physical and chemical properties, showing great potentials in sustainable electrochemical properties and electromagnetic wave protections for human health as well as normal operation of precise electronic devices.