Pebax and CMC@MXene-Based Mixed Matrix Membrane with High Mechanical Strength for the Highly Efficient Capture of CO2

MXenes: Are They Ready for Direct Air Capture of CO2?

Although Direct Air Capture (DAC) of CO2 is a potential technology for climate change mitigation, the cost, scalability, and efficiency of existing materials and techniques are severely limited. MXenes, a type of two-dimensional materials, have drawn interest due to their remarkable conductivity, enormous surface area, and adjustable chemistry, however, their potential for DAC has not yet been thoroughly investigated. Recent developments in MXene synthesis and functionalization are comprehensively reviewed, with an emphasis on how these characteristics might be used to enhance improve CO2 adsorption and capture efficiency. In addition, the difficulties of stability, scalability, and economic feasibility for real-world applications are evaluated. Our findings demonstrate the great potential of MXenes for DAC and offer fresh perspectives on how their special qualities might overcome current constraints. This study presents a new viewpoint on MXenes as a feasible CO2 capture option, indicating new avenues for future research and development, even though further optimization is required.

Flexible composite films constructed of MXene/cellulose nanofibers/natural fiber-based activated carbon fibers for high-performance flexible supercapacitors

Traditional activated carbon fibers (CF) based supercapacitors suffer from low mechanical strength, inherent brittleness that induces stress concentrations, and bulky architectures from binder/conductive additive requirements. To overcome these limitations, cellulose nanofibers (CNF) are synergistically integrated with Ti₃C₂Tₓ MXene and CF, forming a mechanically reinforced composite film via hydrogen bonding and van der Waals interactions. The CNF/CF network expands the interlayer spacing of MXene, which enhances the ion-accessible surface area and enables rapid ion transport. The resulting Ti₃C₂Tₓ/CNF/CF composite film demonstrates exceptional electrochemical performance, achieving a specific capacitance of 420.99 F g-1 at 0.5 A g-1, with 84.56 % retention at 10 A g-1. As a self-supporting flexible electrode (0.49 mm thickness), it delivers an areal capacitance of 214 mF cm-2 at 0.3 mA cm-2 and an energy density of 14.5 μWh cm-2 at 30.2 μW cm-2. The hierarchical CNF/CF network simultaneously suppresses MXene restacking through spatial confinement while optimizing mechanical flexibility and stress distribution via interfacial bonding. This assembly strategy enables scalable fabrication of ultrathin MXene-based supercapacitors suitable for flexible electronics and grid-scale storage systems.

Advancements in Cellulose-Based Materials for CO2 Capture and Conversion

This study explores the recent advances of cellulose-based materials in the context of carbon capture and conversion amid the global imperative to reduce CO2emissions. The review emphasizes the critical importance of selecting suitable materials for establishing a robust and secure carbon capture technology. From elucidating celluloses' molecular structure and unique properties to detailing the advancements in CO2 capture technologies, the narrative provides a comprehensive understanding of the intricate interplay between cellulose and sustainable CO2 management. The exploration extends to the design and synthesis of cellulose-based adsorbents, challenges in implementation, showcasing emerging trends and potential breakthroughs. Emphasizing the significance of cellulose in the circular carbon economy, this review serves as a beacon for interdisciplinary collaboration, urging further research and implementation for a greener and more sustainable future. A comprehensive overview of recent developments on cellulose-based aerogels, films, composites, and solid adsorbents in the field of carbon capture. It further elucidates the research mechanisms involved in utilizing cellulose-based materials to convert CO2 into formic acid, methanol, carbonate, and CO, offering detailed insights. The review concludes by addressing the challenges and key issues associated with cellulose-based materials in the context of carbon capture and utilization.

Carboxymethyl cellulose assisted hydrothermal synthesis of litchi-like zinc ferrite nanoparticles for water remediation through visible photo-Fenton-like catalysis

The conventional methods for the synthesis of zinc ferrite (ZnFe2O4) basically require high temperature calcination oxidation step, which produces environmentally unfriendly high energy consumption and may produce harmful gases that pollute the atmosphere, as well as the calcination synthesis limits the application of ZnFe2O4 such as preparation of organic composite materials. To end this, by adding carboxymethyl cellulose (CMC) to the reaction system, homogeneous litchi-like ZnFe2O4/CMC nanoparticles were successfully synthesized without alkali and calcination in this paper. The rich carboxyl group of CMC is conducive to the chelation and fixation of metal ions in the reaction precursor, which greatly promotes the synthesis of ZnFe2O4. The synthesized particle size is ~100 nm, with obvious ZnFe2O4 diffraction peaks and good crystallinity. The photocatalytic performance of the synthesized photocatalyst was evaluated by visible light-Fenton-like method. With the activation of peroxymonosulfate (PMS), 80.27 % of tetracycline hydrochloride (TC) was degraded in just 18 min, suggesting that the synthesized catalyst had an excellent photocatalytic performance. After four cycles, the catalyst still could degrade 64.52 % TC. And the same behavior in XRD and FTIR spectra confirms the stability of the photocatalyst. In addition, it was determined that singlet oxygen (1O2) dominated the visible light catalytic degradation.

Stabilizing zinc powder anodes via bifunctional MXene towards flexible zinc-ion batteries

Flexible zinc (Zn) batteries have gained considerable attention as wearable energy storage devices because of their inherent safety and high theoretical capacity. However, conventional Zn anodes suffer from dendrite growth, high rigidity, and poor cycling stability issues, hindering their practical application in flexible zinc-ion batteries. Herein, a dendrite-free and flexible Zn anode is designed using direct ink writing (DIW) printed MXene as a flexible and highly conductive current collector and MXene-wrapped Zn powder (ZnP) as the active material by carefully optimising the rheological properties of MXene-based dispersion. As a result, the synergistic effects of the MXene-based current collector and the MXene protective layer promoted dendrite-free Zn deposition and prevented side reactions, achieving an outstanding cycling performance that exceeded 130 h at a high depth of discharge of 30%. When paired with a Vanadium pentoxide (V2O5)-based cathode, the flexible full cell demonstrated stable electrochemical performance under mechanical deformation and can power electronic devices, presenting a promising pathway for the development of flexible zinc-ion batteries.

Synthesis and up-to-date applications of 2D microporous g-C3N4 nanomaterials for sustainable development

In recent years, with the development of industrial technology and the increase of people's environmental awareness, the research on sustainable materials and their applications has become a hot topic. Among two-dimensional (2D) materials that have been selected for sustainable research, graphitic phase carbon nitride (g-C3N4) has become a hot research topic because of its many outstanding advantages such as simple preparation, good electrochemical properties, excellent photochemical properties, and better thermal stability. Nevertheless, the inherent limitations of g-C3N4 due to its relatively poor specific surface area, rapid charge recombination, limited light absorption range, and inferior dispersion in aqueous and organic media have limited its practical application. In the review, we summarize and analyze the unique structure of the 2D microporous nanomaterial g-C3N4, its synthesis method, chemical modification method, and the latest application examples in various fields in recent years, highlighting its advantages and shortcomings, with a view to providing ideas for overcoming the difficulties in its application. Furthermore, the pressing challenges faced by g-C3N4 are briefly discussed, as well as an outlook on the application prospects of g-C3N4 materials. It is expected that the review in this paper will provide more theoretical strategies for the future practical application of g-C3N4-based materials, as well as contributing to nanomaterials in sustainable applications.

Recent advances in the development of MXenes/cellulose based composites: A review

Over the past few years, transition metal carbides, nitrides, and carbonitrides, commonly referred to as MXenes have been discovered and utilized quickly in a range of technical fields due to their distinctive and controlled characteristics. MXenes are a new class of two-dimensional (2D) materials that have found extensive use in a variety of fields, including energy storage, catalysis, sensing, biology, and other scientific disciplines. This is because of their exceptional mechanical and structural characteristics, metal electrical conductivity, and other outstanding physical and chemical properties. In this contribution, we review recent cellulose research advances and show that MXene hybrids are effective composites that benefit from cellulose superior water dispersibility and the electrostatic attraction between cellulose and MXene to prevent MXene accumulation and improve the composite's mechanical properties. Electrical, materials, chemical, mechanical, environmental, and biomedical engineering are all fields in which cellulose/MXene composites are used. These properties and applications-based reviews on MXene/cellulose composite, critically analyze the results and accomplishments in these fields and provide context for potential future research initiatives. It examines newly reported applications for cellulose nanocomposites assisted by MXene. To support their development and future applications, perspectives and difficulties are suggested in the conclusion.