An ice-templating process was used to fabricate polymer/MOF monoliths, specifically chitosan/UiO-66, as adsorbents for water treatment. The ice-templated macropores enhanced mass transport, while the monoliths could be easily recovered from solution. This was demonstrated by the adsorption of methylchlorophenoxypropionic acid (MCPP, a herbicide compound) from dilute aqueous solution. To enhance the stability, the freeze-dried monoliths were treated with NaOH solution, solvent exchanged, and dried. The treated chitosan/UiO-66 monolith achieved an adsorption capacity of 34.33 mg g (a maximum theoretic value of 334 mg g by the Langmuir model), closer to the capacity (36.00 mg g) of the freshly prepared UiO-66 nanoparticles and much higher than that of the NaOH-washed UiO-66 nanoparticles (18.55 mg g), by performing the tests in 60 ppm MCPP solution. The composite monolith could be easily picked up using tweezers and used for recycling tests. Over 80% of the adsorption capacity was retained after three more cycles. The powder X-ray diffraction and N sorption studies suggested the crystalline structure of UiO-66 was destroyed during NaOH washing procedure. This, however, provides the potential to improve the adsorption capacity by developing methods to fabricate true polymer/MOF composites.

All-solid-state Li-metal batteries (ASSLBs) are highly desirable, due to their inherent safety and high energy density; however, the irregular and uncontrolled growth of Li filaments is detrimental to interfacial stability and safety. Herein, we report on the incorporation of piezo-/ferroelectric BaTiO 3 (BTO) nanofibers into solid electrolytes and determination of electric-field distribution due to BTO inclusion that effectively regulates the nucleation and growth of Li dendrites. Theoretical simulations predict that the piezoelectric effect of BTO embedded in solid electrolyte reduces the driving force of dendrite growth at high curvatures, while its ferroelectricity reduces the overpotential, which helps to regularize Li deposition and Li + flux. Polarization reversal of soft solid electrolytes was identified, confirming a regular deposition and morphology alteration of Li. As expected, the ASSLBs operating with LiFePO 4 /Li and poly(ethylene oxide) (PEO)/garnet solid electrolyte containing 10% BTO additive showed a steady and long cycle life with a reversible capacity of 103.2 mAh g −1 over 500 cycles at 1 C. Furthermore, the comparable cyclability and flexibility of the scalable pouch cells prepared and the successful validation in the sulfide electrolytes, demonstrating its universal and promising application for the integration of Li metal anodes in solid-state batteries.

Lithium metal batteries (LMBs) represent next-generation high-energy rechargeable batteries. However, practical applications of LMBs are hindered by their Li anode-related shortcomings including continuous electrolyte decomposition, uncontrollable Li dendrite growth, and...

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There are continuously strong interests for the preparation of carbon and carbon composite materials because of their excellent properties and very broad applications. We report here the fabrication of porous carbon and carbon/metal oxide composites via an ice-templating approach and a carbonization process. Porous polymer and polymer/metal−organic framework (MOF) composites, namely poly(4-styrenesulfonate) and UiO-66 nanoparticles, are first prepared via a simple freeze-casting process. The material morphology and loading of MOF particles can be easily adjusted by varying initial suspension compositions during the freeze-casting process. These ice-templated materials are subsequently carbonized under Ar, producing carbon and carbon/ZrO 2 composites with ice-templated macropores and micropores/mesopores. The carbonized materials are evaluated as adsorbents for dye removal from aqueous solution, exhibiting high performance in general for the adsorption of methylene blue, particularly achieving the high adsorption capacity of 96 mg g −1 (10 mg adsorbent/5 cm 3 aqueous dye solution) with the porous carbon material.