Ang, Edison Huixiang

Multivalent-ion batteries have garnered significant attention as promising alternatives to traditional lithium-ion batteries due to their higher charge density and potential for sustainable energy storage solutions. Nevertheless, the slow diffusion of multivalent ions is the primary issue with electrode materials for multivalent-ion batteries. In this review, the suitability of MXene-based materials for multivalent-ion batteries applications is explored, focusing onions such as magnesium (Mg2+), aluminum (Al3+), zinc (Zn2+), and beyond. The unique structure of MXene offers large interlayer spacing and abundant surface functional groups that facilitates efficient ion intercalation and diffusion, making it an excellent candidate for multivalent-ion batteries electrodes with excellent specific capacity and power density. The latest advancements in MXene synthesis and engineering techniques to enhance its electrochemical performance have been summarized and discussed. With the versatility of MXenes and their ability to harness diverse multivalent ions, this review underscores the promising future of MXene-based materials in revolutionizing the landscape of multivalent-ion batteries.

Graphene-based materials (GBMs) possess a unique set of properties including tunable interlayer channels, high specific surface area, and good electrical conductivity characteristics, making it a promising material of choice for making electrode in rechargeable batteries. Lithium-ion batteries (LIBs) currently dominate the commercial rechargeable battery market, but their further development has been hampered by limited lithium resources, high lithium costs, and organic electrolyte safety concerns. From the performance, safety, and cost aspects, zinc-based rechargeable batteries have become a promising alternative of rechargeable batteries. This review highlights recent advancements and development of a variety of graphene derivative-based materials and its composites, with a focus on their potential applications in rechargeable batteries such as LIBs, zinc-air batteries (ZABs), zinc-ion batteries (ZIBs), and zinc-iodine batteries (Zn-I2Bs). Finally, there is an outlook on the challenges and future directions of this great potential research field.

Wastewater treatment recycling is critical to ensure safe water supply or to overcome water shortage. Herein, we developed metallic Co integration onto MnO nanorods (MON) resulting in a phase-separated synergetic catalyst by creating more Mn(III) via the Jahn–Teller effect and oxygen vacancies and improving the redox capability of Co nanoparticles mediated by a thin carbon layer. Additionally, the N-doped surface carbon network on MON contributes to polar sites, facilitating the enrichment of contaminants around reactive sites, thereby shortening the migration of reactive oxidative species (ROS) toward contaminants. The optimized MnO@Co/C-600 exhibits superior PMS activation efficiency for bisphenol A degradation (0.463 min−1), displaying nearly a 20-fold enhancement in the rate constant compared to Mn3O4/C-600. Subsequent experiments involving variable modulation and extension were conducted to further elucidate the multiple synergistic effects. The mechanism study further confirms the synergy of ˙SO4−, ˙OH, ˙O2−, and 1O2, along with additional electron transfer pathways. The intermediates generated during degradation pathways and their toxicity to aquatic organisms were identified. Notably, a monolith integrated catalyst was explored by anchoring MnO@Co/C-600 onto a tailored melamine sponge based on Ca ion triggered crosslink tactic for the photothermal degradation of bisphenol A, tetracycline and norfloxacin, endowed with easy recovery and good stability. Furthermore, we demonstrated that the total organic carbon removal of multiple contaminants surpassed that of sole contaminants.

The polymerization pathway of contaminants rivals the traditional mineralization pathway in water purification technologies. However, designing suitable oxidative environments to steer contaminants toward polymerization remains challenging. This study introduces a nitrogen-oxygen double coordination strategy to create an asymmetrical microenvironment for Co atoms on Ti3C2Tx MXenes, resulting in a novel Co-N2O3 microcellular structure that efficiently activates peroxymonosulfate. This unique activation capability led to the complete removal of various phenolic pollutants within 3 min, outperforming the representative Co single-atom catalysts reported in the past three years. Identifying and recognizing reactive oxygen species highlight the crucial role of ⋅O2−. The efficient pollutant removal occurs through a ⋅O2−-mediated radical pathway, functioning as a self-coupling reaction rather than deep oxidation. Theoretical calculations demonstrate that the electron-rich pollutants transfer more electrons to the catalyst surface, inducing the reduction of dissolved oxygen to ⋅O2− in the Co-N2O3 microregion. In a practical continuous flow-through application, the system achieved 100 % acetaminophen removal efficiency in 6.5 h, with a hydraulic retention time of just 0.98 s. This study provides new insights into the previously underappreciated role of ⋅O2− in pollutant purification, offering a simple strategy for advancing aggregation removal technology in the field of wastewater treatment.

This review delves into the comparative analysis of nanofiltration (NF) and selective electrodialysis (S-ED) in the separation of Li+ and Mg2+ ions during lithium extraction from salt lakes. The examination is comprehensive, focusing on strategies to enhance selectivity in both methods. The paper outlines the selectivity mechanisms and then synthesizes approaches to improve the intrinsic selectivity of membranes (internal factors) and optimize process conditions (external factors). Moreover, it conducts a comparative analysis, evaluating the strengths, weaknesses, and separation efficiencies of both techniques. Comparative analyses were carried out to conclude that NF shows the higher selectivity relative to S-ED, while S-ED having a higher Li+ recovery than NF. Additionally, NF technology is more mature, due to that a variety of materials for NF membrane in the preparation process can be choosed . In contrast, the materials used for mono-/multi-valent separation cation exchange membranes (CEMs) are relatively limited, and their fabrication process requires higher precision. In conclusion, the review performs a thorough analysis and considers preparation techniques, operational conditions, and other factors on this basis. It proposes a developmental approach tailored to achieve high-selectivity Li+ recovery.

Photothermal catalysis of functional materials triggered by light-irradiation to local heating approach attracts growing attention, but one key detail affecting catalytic thermodynamic process was often ignored that thermal-conductive surface of functional materials directly contacting reaction solution easily delivers heat to the reaction system, leading to weakening heating effect in the interfacial local catalytic microenvironment. Herein, a functional low-thermal-conductivity layer that Mn-coupling porous SiO2 shell layer was constructed over the Co3O4 nanospheres. Specifically, SiO2 with porous channels introduced acts as the thermal-insulation layer to prevent the heat dissipation of the photo-heating core of Co3O4. More importantly, porous channel and inserted MnOx active species could further offer an additive special reaction microenvironment over the photo-heating core of Co3O4. Additionally, the introduction of Mn and structural remodeling through tailored annealing temperature (600–800 °C) can give improved catalytic hybrids abundant valence states and interfacial effects. A series of Co@Mn/m-SiO2 catalysts were fabricated based on the above control tactic. The Co@Mn/m-SiO2 catalysts exhibit superior activating ability for peroxymonosulfate (PMS) to degrade bisphenol A (BPA) and other pollutants including 2, 4-dichlorophenol (2, 4-DCP), phenol (PhOH), oxytetracycline (OTC), and tetracycline (TCN). Specifically, Co@Mn/m-SiO2-700 was shown to achieve complete degradation of 20 ppm BPA in less than 10 min under optimal conditions. In addition, we demonstrated that functional silica layer modified Co3O4 affords a better photo-heating effect compared to bare Co3O4 sphere in air or water, thereby contributing to a faster PMS activation efficiency. Besides, thermal treatment processing for Co@Mn/m-SiO2 catalyst makes the surface reactive species be optimized to generate more beneficial redox pairs and reach excellent photothermal catalytic efficiency in various pollutants treatment.

With the increase in dependence on renewable energy sources, interest in energy storage systems has increased, particularly with solar cells, redox flow batteries, and lithium batteries. Multiple diagnostic techniques have been utilized to characterize various factors in relation to the battery performance. Electrochemical tests were used to study the energy density, capacity, cycle life, rate, and other related properties. Furthermore, it is critical to correlate the information collected from the characterization of materials to its properties while functioning for advanced batteries. In situ and operando electron microscopy methods are specifically designed to conduct such characterization, and analysis was found to be the best method to achieve that objective. However, the characterization information collected varies according to the types of electron microscopy techniques. Also, the use of complementary analytical techniques further provides a more comprehensive study of these different characterizations, giving insights into the morphology-performance relationship of battery materials and interfaces. Within this review, the focus is on in situ and operando electron microscopy characterization of battery materials, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), cryogenic transmission electron microscopy (Cryo-TEM), and three-dimensional (3D) electron tomography. This review aims to cover both advanced electron microscopy imaging techniques and their applications in the characterization of battery materials involving cathode, anode, and separator and solid electrolyte interphase (SEI). The review discusses a range of advanced electron microscopy techniques, including TEM, SEM, and atomic force microscopy, as well as associated analytical techniques such as energy-dispersive X-ray spectroscopy and electron energy loss spectroscopy. The use of these techniques has led to significant advances in our understanding of battery materials, including the identification of new phases and structures, the study of interface properties, and the characterization of defects and degradation mechanisms. Future perspectives on these advanced electron microscopy techniques and opportunities are also discussed. Overall, this review highlights the importance of electron microscopy in battery research and the potential for these techniques to drive future advancements in the field.

Aside from the electrolyte, a separator is another important component in lithium-based batteries that has a direct impact on the safety feature and electrochemical performances. To overcome the thermal shrinkage and poor electrolyte affinity of commonly used polyolefin separators, cellulosed-based separators are appealing due to their abundant polar functional groups, thermal stability, and environmental friendliness, especially for large-sized and high-energy-density batteries. Herein, a porous 3D network of polymer cellulose-based separator modified with polyethyleneimine and polyvinylidene fluoride-hexafluoropropylene was created using a non-solvent induced phase separation approach. The lithium metal batteries consisting of PIC separator can deliver up to a specific capacity of 114 mAh g -1 even at high C-rate of 8 C (1.36 A g -1 ) after 300 cycles. Such superior performances of the lithium metal batteries can be attributed to the good wetting ability (390% electrolyte absorption) and high ionic conductivity (0.754 mS cm -1 ) of the as-prepared PIC separator. More importantly, the introduction of polyethyleneimine as a cross-linking agent significantly improves the mechanical strength of the separator, promote the uniform deposition of lithium and compatibility with high voltage (4.4 V) cathode materials LiNi 0.8 Mn 0.1 Co 0.1 O 2 . This work demonstrates a new strategy for the separator design towards high-performance lithium metal battery applications.

This research focused on creating oxygen vacancy-enriched copper-doped LaFeO3 perovskite using a Prussian blue MOF template. This new material, LFO-Cu, showed outstanding Bisphenol A (BPA) degradation with 98 % efficiency in just 30 min, ten times faster than pure LaFeO3 (LFO). Moreover, the LFO-Cu/peroxymonosulfate (PMS) system worked effectively at pH levels from 4 to 10, breaking down various pollutants (TC, PhOH, MV, MB), and removing 85 % TOC in BPA and 50 % in TC. Density Functional Theory (DFT) calculations revealed that copper strengthened the catalyst-PMS interaction, leading to the generation of highly reactive oxygen species (ROS), primarily singlet oxygen (1O2) and superoxide radicals (O2–·). A degradation pathway was proposed, showing less toxic intermediates than BPA. In summary, copper-doped oxygen-rich vacancy MOFs-derived perovskite has significant potential for improving refractory organic mineralization.

The architectural design of redox-active organic molecules and the modulation of their electronic properties significantly influence their application in energy storage systems within aqueous environments. However, these organic molecules often exhibit sluggish reaction kinetics and unsatisfactory utilization of active sites, presenting significant challenges for their practical deployment as electrode materials in aqueous batteries. In this study, we have synthesized a novel organic compound (PTPZ), comprised of a centrally symmetric and fully ladder-type structure, tailored for aqueous proton storage. This unique configuration imparts the PTPZ molecule with high electron delocalization and enhanced structural stability. As an electrode material, PTPZ demonstrates a substantial proton-storage capacity of 311.9 mAh g−1, with an active group utilization efficiency of up to 89% facilitated by an 8-electron transfer process, while maintaining a capacity retention of 92.89% after 8000 charging-discharging cycles. Furthermore, in-situ monitoring technologies and various theoretical analyses have pinpointed the associated electrochemical processes of the PTPZ electrode, revealing exceptional redox activity, rapid proton diffusion, and efficient charge transfer. These attributes confer a significant competitive advantage to PTPZ as an anode material for high-performance proton storage devices. Consequently, this work contributes to the rational design of organic electrode materials for the advancement of rechargeable aqueous batteries.