Latest ArticlesHollow fiber microfiltration (MF) and ultrafiltration (UF) membrane processes have been extensively used in water purification and biotechnology. However, complicated filtration hydrodynamics wield a negative influence on fouling mitigation and stability of hollow fiber MF/UF membrane processes. Thus, establishing a mathematical model to understand the membrane processes is essential to guide the optimization of module configurations and to alleviate membrane fouling. Here, we present a comprehensive overview of the hollow fiber MF/UF membrane filtration models developed from different theories. The existing models primarily focus on membrane fouling but rarely on the interactions between the membrane fouling and local filtration hydrodynamics. Therefore, more simplified conceptual models and integrated reduced models need to be built to represent the real filtration behaviors of hollow fiber membranes. Future analyses considering practical requirements including complicated local hydrodynamics and nonuniform membrane properties are suggested to meet the accurate prediction of membrane filtration performance in practical application. This review will inspire the development of high-efficiency hollow fiber membrane modules.
Lithium-ion capacitor (LIC), which combines the advantages of lithium-ion battery (LIB) and electrical double layer capacitor (EDLC), has a rapid development during last decade, however, the poor low temperature performance still limits its application. In this paper, three electrolyte additives including vinylene carbonate (VC), fluoroethylene carbonate (FEC) and 1,3,2-dioxathiolane 2,2-dioxide (DTD) have been utilized and their effects on the rate performance of hard carbon (HC) anode of LIC at various temperatures ranging from 25 ℃ to −40 ℃ have been well evaluated. The cell containing FEC shows the best rate performance at various temperatures and has the charge and discharge capability even at −40 ℃. For HC anode, the charge transfer impedance (RCT) increases exponentially at low temperature, while the equivalent series resistance (Rs) and the impedance of solid electrolyte interface (SEI) increase relatively few. At low temperatures, the effect of FEC may be mainly reflected in its effect on the charge transfer process.
Chiral pillar[n]arenes have shown great research value and application prospect in construction of chiral materials and chiral applications, due to their inherent planar chiral configurations, chiral recognition ability, easy modification and highly symmetric hydrophobic cavity. This review systematically summarized the conformation inversion factors of planar chiral Pillar[5]arenes (pR/pS), such as solvents, temperature, substituent size, alkyl chains, chiral and achiral guest molecules. We firstly introduced the applications of chiral pillar[n]arenes for constructing chiral materials and pointed out that planar conformation inversion showed a great potential role in constructing chiral materials. Then, we mainly concluded the chiral applications of chiral and planar chiral pillar[n]arenes like chiral enantiomer analysis by circular dichroism, electrochemistry or chiral fluorescence sensing. From this review, we found that the inherent planar chiral conformation of chiral pillar[n]arenes have played a very important role in chiral field in the future.
Electrochemical degradation performances of three non-steroidal anti-inflammatory drugs (NSAIDs), acetaminophen (ACT), aspirin (ASP) and ibuprofen (IBP), were investigated and compared in their alone and mixture conditions using Ti/SnO2-Sb/La-PbO2. The pseudo-first-order degradation kinetics (k) order was kIBP-A (0.110 min−1) > kASP-A (0.092 min−1) > kACT-A (0.066 min−1) in their alone condition, while that was kACT-M (0.088 min−1) > kASP-M (0.063 min−1) > kIBP-M (0.057 min−1) in their mixture condition. The •OH apparent production rate constant of 5.23 mmol L−1 min−1 m−2 and an electrical energy per order (EEO) value of 6.55 Wh/L could ensure the synchronous degradation of the NSAIDs mixture. The mineralization efficiency of NSAIDs mixture was 86.9% at 240 min with a mineralization current efficiency of 1.67%. Acetic acid and oxalic acid were the main products in the mineralization process for the both conditions. In the mixture condition, there were higher k values at lower initial concentrations and higher current density, while the presence of carbonate and humic acid inhibited their degradation. The results indicated electrochemical advanced oxidation process can effectively and synchronously mineralize NSAIDs mixture in wastewater.
Far-ranging and improper uses of pharmaceuticals and personal care products (PPCPs) over the last few decades have led to severe water contamination that imposes serious effects on human beings and the ecological system. Therefore, there is an increasing demand for a highly-efficient and environmentally friendly technology for the removal of PPCPs from aqueous solutions. Adsorption technology is an appropriate technology to solve this issue. Carbon-based composites, ranging from modified activated carbon to functionalized biochar, show great potential for this purpose. This review hence elaborates on the environmental occurrences and risks of PPCPs and summarizes the recent progress in removing PPCPs from water using carbon-based adsorbents. The pore structure, relatively large specific surface area (SSA), abundant surface functional groups, highly aromatic structures and the extra excellent characteristics of the cooperative materials contribute to their outstanding adsorption performance. Furthermore, the biochar-clay material is cost effective and more efficient compared to traditional activated carbon regarding the adsorption of PPCPs. Among the emerging adsorbents, graphene and carbon nanotubes composites show superior adsorption ability. Their adsorption mechanisms, such as electrostatic interactions, hydrogen bonding, and pore filling, are discussed in details.
Fe-N-C structures have been considered as a candidate to replace noble metal catalysts towards oxygen reduction reaction (ORR) due to their excellent electrocatalytic activity and durability. Herein, a zinc-mediated synthesis strategy is proposed for N-doped graphitic porous carbon encapsulated uniform dispersed Fe3C nanoparticles coupled with atomically dispersed Fe-Nx moieties (NPC/Fe-N-C) derived from biomass coconut shell. The introduction of zinc species could be conductive to the dispersion of iron species and formation of porous structures. Density functional theory calculations demonstrate that the N-doped carbon coating structures can weaken the oxygen intermediates adsorption energy barrier of Fe3C. Beside, the graphitic carbon could promote the electron transfer during the electrochemical reaction. These special structures enable NPC/Fe-N-C to have excellent ORR activity with an Eonset of 1.0 V, which is much better than Pt/C. Furthermore, the zinc-air battery assembled by pairing NPC/Fe-N-C with a high-efficiency oxygen evolution reaction (OER) catalyst can continuously and stably operate a charge-discharge potential gap of 0.8 V at 10 mA/cm2 for more than 600 h. More importantly, the assembled batteries could drive overall water splitting device, realizing the effective energy conversion.
As a common volatile organic compound, benzene (C6H6) exists in home decoration pollution gas widely, which causes great harm to the environment and human health. Therefore, it is necessary to rationally design advanced materials with high selectivity to detect and capture C6H6. Herein, combined with the d-band center theory and cohesive energy, a new two-dimensional metal-organic framework material, Ni-doped hexaaminobenzene-based coordination polymer (Ni-HAB-CP) is designed, and its application potential as a C6H6 sensor are systematically investigated by using first principles calculation. The result shows that Ni-HAB-CP has a strong adsorption for C6H6 without any additional method. In addition, Ni-HAB-CP can maintain good conductivity before and after adsorption, and C6H6 can be easily desorbed from the surface of Ni-HAB-CP by charge control. Moreover, the I-V curve calculated by Atomistix Toolkit (ATK) reveals that Ni-HAB-CP has high sensitivity and selectivity to C6H6. Hence, Ni-HAB-CP is expected to be used as a potential material for a highly efficient and recyclable C6H6 sensor in the future. The calculation and analysis methods used in this paper could provide a certain theoretical basis and reference for the future research of gas sensors.
As environmental crises such as global warming become more and more serious due to the large amount of carbon dioxide emitted by the burning of fossil fuels, much attention has been paid to carbon neutrality. Hydrogen, with zero carbon content, is a clean and renewable energy carrier having a large energy density. It is considered as one of the most desirable alternatives to fossil fuels. Electrochemical water splitting, unlike the steam reforming process accelerating fossil fuels depletion and CO2 emissions, can produce H2 powered by renewable energy such as solar or wind. As a promising way to promote carbon neutralization, hydrogen production by electrolysis of water is meaningful both in terms of scientific research and practical application. In order to drive electrochemical water splitting with low power consumption, efficient, durable and affordable electrocatalysts with low overpotentials are in urgent need. Therefore, this mini-review briefly introduces the current development status and mainstream obstacles of carbon-based materials used in electrochemical water splitting.
Remarkable Li-ion battery (LIB) anode materials need to have long cycle life and fast charge/discharge rate, however they are difficult to be realized in the monolayer anode materials. The monolayer β-Bi has the stiffness of only 33.0 N/m, thus the Bi/G heterostructure is proposed to improve the electronic and mechanical properties and to produce better LIB anode performance in this paper. The calculated results show that Bi/G heterostructure has excellent thermodynamic, dynamical and mechanical stability. The band gap is only 0.04 eV, which ensures remarkable electrical conductivity. In addition, the Bi/G heterostructure has higher stiffness (369.2 N/m) than that of monolayer β-Bi and graphene. The diffusion barrier (Ebarrier) of 0.32 eV and volume expansion ratio (VER) of only 4% can ensure the rapid transport of Li+ ions in the charge/discharge cycling process and long life of the LIB. These calculated theoretical results for describing the detail properties of Li storage and diffusion in the Bi/G heterostructure can supply adequate conclusive evidence for the prediction of remarkable properties of Bi/G heterostructure as an anode material for LIBs.
Eggshell-loaded CoFe2O4 catalyst was synthesized via a convenient hydrothermal method during our work, then the surface morphology and elemental composition of the composites were systematically investigated. Performance of CoFe2O4/eggshell-activated peroxymonosulfate (PMS) system was evaluated by selecting florfenicol (FF) as the model pollutant, and effects of operating parameters and water matrices on the FF removal efficiency in this system were investigated. In addition, main radicals involved in FF degradation were identified by EPR tests and radical quenching experiments, and possible mechanism was proposed. The reduction of toxicity during FF degradation was confirmed, and in combination with HP-LC tests, it was found that dehalogenation and defluorination were effectively carried out during FF degradation. In addition, the prepared CoFe2O4 polyvinylidene fluoride (PVDF) membrane effectively improved the stability of the material and reduced the precipitation of metals.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
