Ang, Edison Huixiang

Recent research has focused on Mn-ion batteries (MIBs) and their associated operations to prepare these batteries for stationary energy storage. The features of MIBs could be defined by establishing a steady Mn2+ storage cathode, which is necessary for understanding their practical challenges. In this study, a Na1.25V3O8 (NVO) cathode prepared by the sol–gel technique with a large interlayer spacing was used as an Mn2+ storage host in two different electrolytes (1 M Mn(ClO4)2 (MC) and 1 M MnSO4 (MS)). The MC electrolyte with stable charge transfer kinetics exhibited better electrochemical performance than the MS electrolyte. Theoretical analyses support that the semiconducting NVO cathode becomes conducting when Mn ions are intercalated into the structure, which helps to understand the stable Mn2+ storage properties in a coin-cell configuration.

The recycling of lithium-ion battery (LIB) ternary cathodes has become increasingly vital due to the surging demand for electric vehicles (EVs), renewable energy storage, and portable electronics. These cathodes, primarily composed of nickel (Ni), cobalt (Co), and manganese (Mn), offer high energy density but face significant challenges tied to resource scarcity, environmental impacts, and the complexity of recycling processes. This review emphasizes the urgent need for sustainable recycling solutions, driven by the depletion of critical resources and the environmental footprint of LIB production and disposal. It provides a detailed examination of recycling advancements from 2020 to 2025, focusing on mechanical, pyrometallurgical, hydrometallurgical, biotechnological, and emerging direct recycling methods, while addressing key failure mechanisms. Despite progress in recovery efficiency and material purity, challenges such as low recovery rates, high costs, and intricate battery designs remain. The review also explores future directions, including innovations in recycling technologies, battery designs optimized for recyclability, economy effects, and greater automation. Moreover, the integration of artificial intelligence (AI) further accelerates progress by enhancing battery monitoring, optimizing recycling processes, and driving innovation in material design and industrial-scale recycling, paving the way for a sustainable LIB ecosystem.

Sustainable and energy-efficient water purification by harnessing solar energy is critical to tackling the challenges of water scarcity and the on-going water pollution crisis. Nevertheless, the biggest challenge to the practical deployment of solar-driven water purification, however, continues to be the poor solar evaporation efficiency of materials. Herein, FeNi nanoalloys encapsulated in graphitic carbon nanofibers (FeNi3/CNF) using Prussian blue analogue (PBAs) derivatives were fabricated using electrospinning and carbonization. The PBAs metal precursors play a critical role in encapsulating and safeguarding the FeNi alloy nanostructures from oxidation and agglomeration challenges. Furthermore, the synergistic effects between the non-noble hybrid plasmonic nanoalloys and graphitic CNFs can be constructed and optimized from the mass loading of PBAs precursor. Benefiting from the broad solar absorption band, high specific surface area, abundant micro-mesopores, and well-organized interlayer channel, the resultant 2D FeNi3/CNF solar evaporator demonstrates an efficient water evaporation rate of 1.51 kg m-2h−1 with an outstanding solar evaporation efficiency of 93.3 % under one sun irradiation, among the best values reported thus far. Impressively, the resultant 2D FeNi3/CNF solar evaporator can be constructed using only 0.02 kg m−2 loading of photothermal materials without compromising evaporation performance, which highlights its cost-efficiency in the practical application. Furthermore, the desalinated water meets the drinking standards of the World Health Organization (WHO) with an efficient 99 % separation of multiple organic industrial dye pollutants. Hence, this work demonstrates an efficient cost-effective approach to novel non-noble plasmonic alloy-based metal–carbon composites for enhanced solar-driven interfacial evaporation and wastewater purification.

In situ liquid phase transmission electron microscopy (TEM) and three-dimensional electron tomography are powerful tools for investigating the growth mechanism of MOFs and understanding the factors that influence their particle morphology. However, their combined application to the study of MOF etching dynamics is limited due to the challenges of the technique such as sample preparation, limited field of view, low electron density, and data analysis complexity. In this research, we present a study employing in situ liquid phase TEM to investigate the etching mechanism of colloidal zeolitic imidazolate framework (ZIF) nanoparticles. The etching process involves two distinct stages, resulting in the development of porous structures as well as partially and fully hollow morphologies. The etching process is induced by exposure to an acid solution, and both in situ and ex situ experiments demonstrate that the outer layer etches faster leading to overall volume shrinking (stage I) while the inner layer etches faster giving a hollow morphology (stage II), although both the outer layer and inner layer have been etched in the whole process. 3D electron tomography was used to quantify the properties of the hollow structures which show that the ZIF-67 crystal etching rate is larger than that of the ZIF-8 crystal at the same pH value. This study provides valuable insights into MOF particle morphology control and can lead to the development of novel MOF-based materials with tailored properties for various applications.

Along with the cathode, anode, and liquid electrolyte in lithium-based secondary batteries, the separator is a crucial element for guaranteeing battery safety. However, conventional polyolefin separators suffer from inherent drawbacks such as inadequate compatibility with electrolytes and limited thermal stability. These limitations can lead to issues like high-temperature shrinkage, melting, and even combustion. Moreover, the vulnerability of separators toward lithium dendrite penetration exacerbates safety concerns associated with lithium-ion batteries. Hence, the design of high safety separators is currently a focus and challenge. In this study, we develop a multifunctional polymer-coupled nanofiber membrane by an electrospinning method that addresses the above issue as a separator of lithium metal battery. The nanofiber coating contains carbonyl oxygen, pyrrole nitrogen, and cross-linked networks with tertiary amine groups. These components effectively neutralize acidic compounds generated during the liquid electrolyte side reaction. X-ray micro-computed tomography analysis verifies the exceptional structural stability of the new separator, maintaining its 3D skeleton even after 2000 h of cycling. The nanofiber separator in a full Li

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 reuse of waste biomass has received more and more attention in recent years due to resource and environmental problems. The development of green, environmentally friendly and cost-effective electrode materials for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) is currently the focus of research as key electrochemical energy storage systems. Herein, a facile strategy is adopted to prepare 3D hierarchical porous carbon anodes for LIBs/SIBs by taking advantage of waste crab shells and iron p-toluenesulfonate. The results show that the reversible specific capacity of the prepared anode could reach 703.2 mAh g⁻¹ in LIBs and 283.2 mAh g⁻¹ in SIBs when the current density is 0.05 A g⁻¹. In addition, the contributions of pseudocapacitance, the kinetic characteristics and the storage mechanisms of lithium/sodium ions are investigated through cyclic voltammetry (CV) and galvanostatic intermittent titration techniques (GITTs). Due to the unique structure, the obtained material displays an excellent electrochemical performance, which lays the foundation for the improvement in the performance of waste biomass in LIBs/SIBs.

The zinc (Zn) anode of aqueous zinc-ion batteries (AZIBs) faces significant challenges, including dendritic growth, hydrogen evolution reactions, and corrosion, which impede their commercial application. Here, we present a strategy for creating an artificial surface coating layer, Zn-polyethylenimine (Zn-PEI) coordination polymer, formed on the Zn anode surface. The robust Zn-PEI protective layer, rich in amine groups, accelerates ion transport and provides a uniform electric field, thereby suppressing dendrite formation. Additionally, this layer prevents direct contact between the Zn surface and the electrolyte, reducing other side reactions such as hydrogen evolution, surface corrosion, and passivation. The charged amine groups in PEI preferentially expose the Zn (101) crystal plane, which has weak thermodynamic stability, to achieve ordered and densely packed Zn (101) deposition. Consequently, Zn-PEI@Zn//Zn-PEI@Zn symmetric cells exhibit a remarkable cycling life of over 2000 h under the conditions of 1 mA cm−2 and 1 mAh cm−2, and Zn-PEI@Zn//Cu asymmetric cells maintain an average coulombic efficiency of 99.7 % after 1000 stable cycles. This strategy effectively addresses the inherent issues of dendrite growth and hydrogen evolution in Zn anodes, laying a solid foundation for the development of high-performance AZIBs.

Aqueous zinc‐ion batteries (AZIBs) have received significant research attention and widely investigated because of their high intrinsic safety and cost effectiveness. Manganese dioxide has been regarded as a promising cathode material for AZIBs, attributed to its friendliness, abundant resources, high theoretical capacity, and high working voltage. Herein, a unique one-dimensional–three-dimensional (1D–3D) hybrid network with interconnected δ-MnO2 nanowires was reported as a cathode material for AZIBs. A distinctive 3D nano network structure resulted in enhancement of electrolyte osmosis and significant increase in contact between electrode and electrolyte, and also provided more active sites and convenient rapid ion transport routes. Moreover, the fine nanowire structure and the optimum layer spacing resulted in easier insertion/deinsertion of ion in the active material. Taking advantage of this feature, the δ-MnO2 cathode provides high reversible capacity, fast rate capability and good longevity for cycling. Further kinetic experiments revealed that Zn/δ‐MnO2 system constitutes an electrochemical reaction regulated by the combination of ionic diffusion and pseudo-capacitance; and shows high energy efficiency during the charge/discharge states. This research may provide an advanced cathode material for AZIB development.

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.