Ang, Edison Huixiang

The availability of clean water is fundamental for maintaining sustainable environments and human ecosystems. Capacitive deionization offers a cost-effective, environmentally friendly, and energy-efficient solution to meet the rising demand for clean water. Electrode materials based on pseudocapacitive adsorption have attracted significant attention in capacitive deionization due to their relatively high desalination capacity. In this study, a novel organic compound, PTQN, is introduced, featuring a ladder-type structure enriched with imine-based active sites, specifically designed for capacitive deionization. This advanced molecular design imparts the PTQN compound with exceptional pseudocapacitive properties, enhanced electron delocalization, and superior structural stability, which are supported by both experimental results and theoretical analyses. As an electrode, PTQN exhibits a high pseudocapacitive capacitance of 238.26 F g−1 and demonstrates excellent long-term stability, retaining approximately 100 percent of its capacitance after 5000 cycles in NaCl solution. The involvement of PTQN active sites in the Na+ electrosorption process was further elucidated using theoretical calculations and ex situ characterization. Moreover, a hybrid capacitive deionization (HCDI) device employing the PTQN electrode exhibited an impressive salt removal capacity of 61.55 mg g−1, a rapid average removal rate of 2.05 mg g−1 min−1, and consistent regeneration performance (∼97.04 percent after 50 cycles), demonstrating its potential for capacitive deionization systems. Furthermore, the PTQN electrode displayed superior removal efficiency for tetracycline. This work contributes to the rational design of organic materials for the development of advanced electrochemical desalination systems.

Meeting the growing demands of attaining clean water regeneration from wastewater and simultaneous pollutant degradation has been highly sought after. In this study, nanometric CuFe2O4 and plasmonic Cu were in situ confined into graphitic porous carbon nanofibers (CNF) through electrospinning and controlled graphitization, which were integrated onto a melamine sponge (S-FeCu/CNF) as a monolithic evaporator via a calcium ion-triggered network crosslinking method using sodium alginate (SA). This monolithic evaporator serves a dual purpose: harnessing solar-driven photothermal energy for water regeneration and facilitating synchronous contaminant mineralization through advanced oxidation processes (AOPs). The metal-modified FeCu/CNF graphitic porous carbon exhibited an enhanced light absorption property (≥95%) and was further securely anchored on the sponge by a calcium ion-triggered SA crosslinking technique, thereby efficiently restraining salt deposition. The FeCu/CNF evaporator demonstrated a solar-vapor conversion efficiency of 105.85% with an evaporation rate of 1.61 kg m−2 h−1 under one sun irradiation. The evaporation rate of the monolithic S-FeCu/CNF evaporator is close to 1.76 kg m−2 h−1, and an evaporation rate of 1.54 kg m−2 h−1 can be achieved even in 20% NaCl solution, with resistance to salt deposition and cycling stability. Synchronously, the monolithic D-S-FeCu/CNF evaporator also acts as a heterogeneous catalyst to activate peroxymonosulfate (PMS) and trigger rapid pollutant degradation, which also shows excellent catalytic cycling stability, producing clean water that satisfies the World Health Organization (WHO) standards. This work provides a potentially valuable solution for addressing desalination and wastewater treatment.

Unraveling the robust self-adaptivity and minimal energy-dissipation of soft reticular materials for environmental catalysis presents a compelling yet unexplored avenue. Herein, a top-down strategy, tailoring from the unique linkage basis, flexibility degree, skeleton electronics to trace-guest adaptability, is proposed to fill the understanding gap between micro-soft covalent organic frameworks (COFs) and photocatalytic performance. The thio(urea)-basis-dominated linkage within benzotrithiophene-based COFs induce the framework contraction/swelling (intralayer micro-flexibility) in response to tetrahydrofuran or water. Adaptability of micro-flexible thiourea-COF with pore hydrophilicity not only contributes to the favorable mass transfer, but also enhances the accessible redox active sites, culminating in nearly 100% removal of micropollutant with low-energy dissipation in wastewater. The incorporating urea/thiourea into imine linkage facilitates polarization reduction and exciton dissociation within skeleton wall, inducing strong localization for holes. This transformation facilitates interchain charge transport and unbalanced distribution conducive to oxidative holes-mediated micropollutant decomposition.

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.

The current understanding of the mechanism of high-entropy layered double hydroxide (LDH) on enhancing the efficiency of activating peroxymonosulfate (PMS) remains limited. This work reveals that a strong strain effect, driven by high entropy, modulates the structure of FeCoNiCuZn-LDH (HE-LDH) as evidenced by geometric phase analysis (GPA) and density functional theory (DFT) calculations. Compared to FeCoNiZn-LDH and FeCoNi-LDH with weaker strain effects, the high entropy-driven strain effect in HE-LDH shortens metal–oxygen-hydrogen (Msingle bondOsingle bondH) bond lengths, allows system to be in a constant steady state during catalysis, reduces the leaching of active M−OH sites, and enhances the adsorption capacity of these sites and the excess strain strength of the interfacial stretches the IO-O of the PMS, facilitates reactive oxygen species (·OH, SO4·−, 1O2 and O2·-) generation, and thereby improving the efficiency of PMS in degrading tetracycline (TC). Consequently, HE-LDH demonstrated a 90% TC degradation within 3 min, maintained over 92% TC removal across a wide pH range (3–11), and achieved over 90% degradation performance after 6 cycles. This study reports the first use of high-entropy LDH material as a non-homogeneous catalyst and provides insights into the extremely different catalytic behaviors of high entropy mechanisms for the activation of PMS.

Bionic evaporators inspired by natural plants like bamboo and mushrooms have emerged as efficient generators through water capillary evaporation. However, primitive natural evaporators cannot currently meet growing demand, and their performance limitations remain largely unexplored, presenting a substantial challenge. Through extensive experimentation and detailed simulation analysis, this study presents a precisely engineered H-type bamboo steam generator. This innovative design incorporates a unique node structure embedded with graphite flakes and an internode characterized by micro- and nanoporous channels, all achieved through streamlined carbonization. The results are striking: a water evaporation rate of 2.28 kg m−2 h−1 and a photothermal conversion efficiency of 90.2% under one-sun irradiation, outperforming comparable alternatives. This study also marks the first comprehensive simulation in COMSOL modeling water capillary evaporation, driven by the synergistic effects of photothermal graphitic layers, broad-spectrum solar absorption, and capillary microstructures. The chimney-assisted, enclosed cavity structure further enhances water capillary evaporation and thermal localization. This breakthrough not only enables efficient use of waste biomass but also advances the field of sustainable materials, opening new avenues in solar-driven steam generation.

A novel Fe-N2O1S1 single-atom catalyst (FeSA-NS-Ti3C2Tx) was developed for dual activation of ultra-low concentration peroxymonosulfate (PMS) and dissolved oxygen in wastewater treatment. The catalyst was synthesized via a multivariate heteroatom doping strategy using transition metal salt solution and thiourea on Ti3C2Tx. Under 0.1 mM PMS, the FeSA-NS-Ti3C2Tx achieved 100 % acetaminophen (20 μM) removal within 6 min, with a Kcmp of 889.77 min−1 g−2 L2 and a turnover frequency over two orders of magnitude higher than homogeneous Fe2+/Fe3+ and iron oxides. Mechanistic analysis and theoretical calculations showed that the asymmetric Fe-N2O1S1 site optimizes the generation of ·O2− and 1O2, efficiently removing ACE through deacetylation and electrophilic attack on the benzene ring. In the long-term tests, the iron leaching of the high-density catalytic bed is negligible, ensuring environmental safety. This study highlights a cost-effective and scalable strategy to advance PMS-based advanced oxidation technologies in wastewater treatment.

abstract

Metal-organic frameworks (MOFs), with their ultrahigh specific surface area, uniformly distributed pores, and tunable structures, are promising candidates for next-generation active electrode materials in lithium-ion batteries (LIBs). However, their application is hindered by poor cycling stability due to structural collapse during charge-discharge cycles. To address this issue, we developed an alloy and multi-solvent thermal method strategy to synthesize Co/Zn bimetallic MOFs based on Naphthalenetetracarboxylic acid (NTCA). The resulting petal-like Co/Zn-NTCA MOF demonstrates outstanding electrochemical performance. The incorporation of zinc ions not only significantly enhances cycling stability but also markedly increases the specific capacity of the anode material. At a current density of 200 mA·g–1, the Co/Zn (2:1)-NTCA MOF demonstrated an impressive reversible capacity of 956 mA·h g–1 after 150 cycles. Even after 500 cycles, the specific capacity of the electrode remained high, with a value of 438 mA·h g–1 at a current density of 1000 A·g–1.

The synthesis of high-quality two-dimensional covalent organic frameworks (2D COFs) under mild conditions is crucial for their wide scale industrial application. Therefore, the advancement of the unidirectional diffusion synthesis (UDS) method has garnered significant attention. A comprehensive understanding of the diffusion dynamic occurring between the two phases is vital for optimizing reaction times and enhancing the growth conditions of highly crystalline COF films. In this work, we employed the UDS method, explored through various characterization tests, to fabricate 2D COFs on commercial PAN ultrafiltration membranes. Our study shows that the COF layer forms on one side contacting with the organic phase, regardless of whether the front side of the PAN-based film is exposed to the aqueous or organic phase. Through the different reaction times, it was found that the 2-min treatment yielded the optimal performance, with a pure water permeability coefficient of approximately 98 L·m−2·h−1·bar−1, along with a retention rate of exceeding 95 % for both CR and AR 120. Furthermore, it surpassed the interfacial polymerization method in terms of both stability and retention capacity for EBF molecules with molecular weights under 500 g·mol−1.