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Lead-free dielectric ceramics are one of the most essential candidates for reforming pulsed power capacitors; nevertheless, formidable hurdles are posed by their high hysteresis and low energy storage properties. Dielectric ceramic capacitors with ultra-high energy storage performance usually need to be realized under the conditions of high electric field. Its application in miniaturized integrated electronic devices is severely limited. In this work, A-site deficiency was designed in Na0.97Bi0.01TaO3-modified Bi0.48Na0.48Ba0.04TiO3 lead-free relaxor ferroelectric ceramics to increase oxygen vacancy content, achieve local disorder and construct local multi-phase coexistence, which causes low hysteresis with excellent high energy density at low electric fields (LEFs). Results indicated that the introduction of A-site deficiency improved the concentration of oxygen vacancies while reconstructing the local structure disorder. Benefiting from the synergistic effect of both, a high energy recoverable density of ∼7.98 J cm−3 and efficiency η of ∼83.7% was determined in 0.84Bi0.48Na0.48Ba0.04TiO3-0.16Na0.97Bi0.01TaO3-modified ceramics under 330 kV cm−1. Furthermore, the modified ceramics had an acceptable frequency stability (0.5–130 Hz) and temperature stability (RT – 180 °C) with exact discharge density. These findings can lead to the development of an innovative strategy for fabricating energy-storage ceramics under low electric field conditions. [ABSTRACT FROM AUTHOR]

Porous organic polymers (POPs) constitute an important class of sorbents studied in various adsorption and separation processes. Their unique properties, including high surface areas, adjustable pore sizes, and surface chemistries make them ideal candidates for CO2 capture. To achieve a high CO2 adsorption capacity and selectivity, particularly at the low partition pressures required for post‐combustion CO2 capture or direct capture of CO2 from the atmosphere, incorporating amines onto the polymer frameworks or within the pores has shown much promise. This review provides a comprehensive summary of recent studies on the synthesis and CO2 capture performance of amine‐functionalized POPs. The review also provides a detailed discussion of structure‐performance relationships, focusing on how the loading amount and amine type influence CO2 capture capacity, CO2/N2 selectivity, heat of adsorption, sorption kinetics, and recyclability of POPs. Additionally, the authors offer their perspective on the challenges associated with the practical implementation of amine‐modified POPs for CO2 capture. [ABSTRACT FROM AUTHOR]

Porous organic polymers (POPs) with high porosity and tunable functionalities have been widely studied for use in gas separation, catalysis, energy conversion and energy storage. However, the high cost of organic monomers, and the use of toxic solvents and high temperatures during synthesis pose obstacles for large‐scale production. Herein, we report the synthesis of imine and aminal‐linked POPs using inexpensive diamine and dialdehyde monomers in green solvents. Theoretical calculations and control experiments show that using meta‐diamines is crucial for forming aminal linkages and branching porous networks from [2+2] polycondensation reactions. The method demonstrates good generality in that 6 POPs were successfully synthesized from different monomers. Additionally, we scaled up the synthesis in ethanol at room temperature, resulting in the production of POPs in sub‐kilogram quantities at a relatively low cost. Proof‐of‐concept studies demonstrate that the POPs can be used as high‐performance sorbents for CO2 separation and as porous substrates for efficient heterogeneous catalysis. This method provides an environmentally friendly and cost‐effective approach for large‐scale synthesis of various POPs. [ABSTRACT FROM AUTHOR]

As the most abundant green and renewable resource in nature, cellulose has received the researchers' attention because of its excellent properties. In this paper, novel renewable cellulose-derived nano-CuO@carbon aerogel composites (CNCAs) were successfully prepared by freeze-drying, carbonization and dipping, which can be used for efficient oil–water separation. The relevant results disclosed that CNCAs exhibited superhydrophobicity with a water contact angle of 158° ± 2° and outstanding water–oil separation property with separation efficiency of 92.3%. More interestingly, the CNCAs can effectively separate oil from water in surfactant stabilized water-in-oil emulsions with high flux and filtrate purity. The as-prepared CNCAs have durable superhydrophobic and excellent adsorption capacity even after storing in various harsh environments for a long time, such as strong acid and strong alkali etc. Therefore, CNCAs have a good application prospect in the oil–water separation field, providing an effective and feasible solution for the treatment of oily wastewater. [ABSTRACT FROM AUTHOR]

This work presents an effective method of fabricating hierarchical Al2O3/SiO2 fiber membrane with reversible wettability for on-demand oil/water separation. In this strategy, the superhydrophilic/underwater superoleophobic surfaces are fabricated by in-situ growing hierarchical Al2O3 nanosheets on the SiO2 fiber surfaces that can be used as water-removing materials for oil/water separation. Then, the superhydrophobic/oleophilic surfaces are obtained by surface chemical modification with sodium laurate, which can be used as oil-removing materials for oil/water separation. Interestingly, the reversible wettability transformation of Al2O3/SiO2 fiber membrane can be controlled by the annealing and modification treatment alternately. The as-prepared Al2O3/SiO2 fiber membrane, combining the advantages and overcoming disadvantages of two modes, achieves reversible wettability transitions and on-demand oil/water separation. In addition, the Al2O3/SiO2 fiber membrane shows a significant chemical stability and super-wettability even after five annealing and surface modification cycles, indicating its excellent durability. The separation efficiency in both oil-removing mode and water-removing mode is over 95% for various oil/water mixtures through multiple recycle separation processes. This work not only provides a simple and cost-effective method to fabricate separation membrane with reversible wettability, but also shows great potential in remediation of large-scale oil spillage or organic solvents discharge at different environmental conditions. [ABSTRACT FROM AUTHOR]

Acrylic ester resin (AER) is a promising oil‐absorbing material for oils and organic solvents absorption because it exhibits high oil retention ability, good swelling properties, and reusability while also being inexpensive, large‐scale production, and environmentally benign. However, the AER is not fully utilized owing to its low oil absorption capacity and slow oil absorption rate. In this work, we combine porous structures of MnO2 and swelling properties of AER and design a novel route to fabricate sea urchin‐like MnO2/AER hybrids. In this route, the sea urchin‐like MnO2 was prepared by a facile hydrothermal method in acidic media. The sea urchin‐like MnO2/AER hybrids with different wt% were synthesized by a microwave polymerization route. The resin hybrids exhibited very rough surfaces, which are beneficial for organic molecules absorption and diffusion into the interiors of materials. The resin hybrids can remove oils and organic solvents from water with high selectivity and absorption capacity, and can absorb not only floating oil but also heavy organic solvents underwater. The maximum absorption capacity of resin hybrids was found at the MnO2 content of 3%, and maximum absorption capacity up to 32.5 times of their own weight, higher than that of the pure AER. The performances were mainly attributed to the unique porous structure of MnO2 and swelling properties of AER, indicating the potential application of such oil‐absorbing resins to introduce the porous inorganic materials for developing new oils and organic solvents absorbent for removal of organic pollutants from the wastewater. POLYM. COMPOS., 39:4041–4049, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Acrylic ester resin (AER) is a promising oil‐absorbing material for oils and organic solvents absorption because it exhibits high oil retention ability, good swelling properties, and reusability while also being inexpensive, large‐scale production, and environmentally benign. However, the AER is not fully utilized owing to its low oil absorption capacity and slow oil absorption rate. In this work, we combine porous structures of MnO2 and swelling properties of AER and design a novel route to fabricate sea urchin‐like MnO2/AER hybrids. In this route, the sea urchin‐like MnO2 was prepared by a facile hydrothermal method in acidic media. The sea urchin‐like MnO2/AER hybrids with different wt% were synthesized by a microwave polymerization route. The resin hybrids exhibited very rough surfaces, which are beneficial for organic molecules absorption and diffusion into the interiors of materials. The resin hybrids can remove oils and organic solvents from water with high selectivity and absorption capacity, and can absorb not only floating oil but also heavy organic solvents underwater. The maximum absorption capacity of resin hybrids was found at the MnO2 content of 3%, and maximum absorption capacity up to 32.5 times of their own weight, higher than that of the pure AER. The performances were mainly attributed to the unique porous structure of MnO2 and swelling properties of AER, indicating the potential application of such oil‐absorbing resins to introduce the porous inorganic materials for developing new oils and organic solvents absorbent for removal of organic pollutants from the wastewater. POLYM. COMPOS., 39:4041–4049, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Porous organic polymers (POPs) with high porosity and tunable functionalities have been widely studied for use in gas separation, catalysis, energy conversion and energy storage. However, the high cost of organic monomers, and the use of toxic solvents and high temperatures during synthesis pose obstacles for large-scale production. Herein, we report the synthesis of imine and aminal-linked POPs using inexpensive diamine and dialdehyde monomers in green solvents. Theoretical calculations and control experiments show that using meta-diamines is crucial for forming aminal linkages and branching porous networks from [2+2] polycondensation reactions. The method demonstrates good generality in that 6 POPs were successfully synthesized from different monomers. Additionally, we scaled up the synthesis in ethanol at room temperature, resulting in the production of POPs in sub-kilogram quantities at a relatively low cost. Proof-of-concept studies demonstrate that the POPs can be used as high-performance sorbents for CO 2 separation and as porous substrates for efficient heterogeneous catalysis. This method provides an environmentally friendly and cost-effective approach for large-scale synthesis of various POPs., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)