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[Display omitted] • A hydrogen-bond binding strategy is proposed to fabricate iCOF nanosheets (iCONs) and tannic acid (TA) composite membranes. • TA nanoaggregates were synthesized as hydrogen-bond binders. • Abundant hydrogen-bond interactions enable flexible connection between iCONs. • Highly interconnected hydrogen-bond networks facilitate rapid proton transport. • The membranes showed both enhanced mechanical properties and proton conductivity. Robust and highly conductive proton exchange membrane (PEM) is the unremitting pursuit of numerous electrochemical energy technologies such as fuel cell and the emerging electrochemical hydrogen compression. Ionic covalent organic framework nanosheets (iCONs) with long-range ordered nanochannels and abundant ionic groups show substantial potential as next-generation PEM materials. However, it is challenging to assemble iCONs into membranes with both robustness and flexibility due to the electrostatic repulsion and rigid framework. Herein, we propose a hydrogen-bond binding strategy to fabricate sulfonic iCON (SCON) composite membranes by co-assembling tannic acid (TA) nanoaggregates and SCONs. The abundant and dynamically reversible hydrogen-bond interactions introduced by TA nanoaggregates establish effective linkage between SCONs and allow some restricted movements, endowing membranes with remarkably improved mechanical properties. The stacked SCONs construct long-range ordered nanochannels with well-arranged sulfonic groups in membranes, and the hydrogen-bond networks further facilitate the proton transport through Grotthuss mechanism. Consequently, TA/SCON composite membranes displays significantly enhanced tensile strength of 101.9 MPa, good flexibility and high proton conductivity of 490.1 mS cm−1 at 80 °C and 100 % RH simultaneously. This hydrogen-bond binding strategy offers a promising approach to fabricate robust and highly conductive PEMs for various proton-conducting applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Forced flow processing for in-situ exfoliation and dispersion of Gt is proposed. • Backflow and extremely strong shear stress lead to the interlayer loosening of Gt. • 70 wt% of Gt in aPLA can be fully converted into uniformly dispersed GNPs. Graphene has received extensive attention from the industry due to its extraordinary physical and chemical properties. However, the development of low-cost, large-scale methods to prepare graphene and its derivatives via graphite (Gt) exfoliation is still a challenge. Herein, we propose a novel method to in-situ exfoliate and disperse Gt without any post-processing via exploiting the strong shear stress and irreducible deformation generated by the forced flow processing of highly elastic amorphous polylactide (aPLA). It is amazing that, after 8 times forced flow processing within 10 min, 70 wt% of Gt in aPLA is fully converted into uniformly dispersed graphite nanoplatelets (GNPs) with average lateral sizes of 2.28 μm and thicknesses of 8.82 nm. Mechanism analysis reveals that the combination of backflow with subsequent extremely strong shear stress results in the interlayer loosening of graphite toward continuous production of GNPs. The GNPs exhibit exceptional enhancements in the thermal and electrical conductivity of the composites. This ultra-efficient, extremely simple and solvent-free method can be scalable for industrial use. [ABSTRACT FROM AUTHOR]

[Display omitted] • 1. Electrochemical hydrogen compression (EHC) can purify and compress hydrogen in one step. • 2. Working principle and module design of EHC are described and summarized. • 3. Developments of advanced proton-conducting membranes for EHC are reviewed. • 4. Challenges, future trends and prospects of EHC are discussed. Electrochemical hydrogen compression (EHC), which can purify and compress hydrogen in one step, has aroused broad interests due to its high efficiency, compact equipment, and quiet operation. Since the concept of EHC was proposed, considerable efforts have been devoted to this field. In this review, several aspects of EHC are comprehensively discussed. Firstly, the working principle of EHC is presented with a focus on the electrode reactions, overpotentials, and performance indicators. Subsequently, the major functions, required properties, common materials and recent progress on the design and development of EHC modules are overviewed. As the key part of EHC, recent advances in proton-conducting membranes are particularly summarized, including polymeric proton exchange membranes, mixed matrix proton exchange membranes, and proton ceramic oxide membranes. The focus is on the chemical structures, proton transfer mechanisms, factors affecting performances, and applications for hydrogen purification and compression. Finally, the challenges, future trends, and prospects associated with each module of EHC are discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Smart COF membranes were constructed via biomimetic nanochannel modulation. • Charged and switchable channels endowed COF membranes with high ion selectivity. • Pore size of photo-responsive COF membranes was controllable at angstrom level. • Photo-responsive COF membranes showed great potential in lithium extraction. Smart nanochannels can regulate ion transport behavior by external stimulus and display precise ion selectivity in biological membrane systems, but constructing artificial membranes with responsive and tunable channel remains a severe challenge. Herein, smart covalent organic framework (COF) membranes decorated with photo-responsive azobenzene derivatives (COF-Azo) were fabricated by a biomimetic nanochannel modulation (BNM) strategy, endowing membranes with charged and switchable sub-nanochannels. Under different wavelength of light, the smart COF-Azo membranes simultaneously exhibited outstanding mono/monovalent and mono/divalent ion selectivity (K+/Li+ ideal selectivity of 17.9 and Li+/Mg2+ ideal selectivity of 24.9) via closing and opening channels. The conversion of effective pore size at angstrom level is realized by photoisomerization of azobenzene. After several photoswitch cycles, the smart membranes still maintained K+/Li+ selectivity of 6.1 and Li+/Mg2+ selectivity of 20.7 in mixed salt solution, exhibiting great potentials in lithium extraction. This work may blaze a trail in constructing photo-responsive nanochannel membranes for energy-efficient ion separation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A versatile coating was fabricated based on an electrostatic-coordination strategy. • The textile exhibited excellent solar/Joule heating performances properties. • The textile presented passive radiative heating properties. • The textile could protect the human body effectively in practical environments. • The research brought new insights into the development of PTM devices. The development of multifunctional textile-based personal thermal management devices is a prospective option for accurately warming the human body while effectively reducing energy consumption. However, existing multifunctional thermal management devices still face challenges in terms of high-performance integration. Here, we proposed an electrostatic-coordination-based strategy to fabricate successfully a versatile textile for body warming via sequentially covering cotton fiber with bio-based polyelectrolyte and in-situ grown copper sulfide coatings. The textiles with excellent solar/Joule heating properties and reduced infrared emissivity can efficiently heat the body in various environments and suppress thermal radiation dissipation from the body to the environment. Also, the textile realizes high-performance integration of electromagnetic shielding, UV protection, antimicrobial, and flame-retardant properties. This universal and efficient strategy provides a promising solution for the manufacture of all-day and energy-saving versatile personal thermal management devices, showing great potential for practical applications. [ABSTRACT FROM AUTHOR]