查看更多>>摘要：Effective degradation of low-concentration pollutants is a critical challenge during the water purification process. The use of different chemicals can leave residue in samples that can impose potential ecotoxico-logical and adverse impacts on human health. Presently, Magnetic molecularly imprinted polymers (M-MIPs) have attracted much attention as the research material comprises a non-magnetic polymer and magnetic material for selective binding for target molecule and recoverability of catalyst via magnetism, respectively. This review explains the synergistic effect of adsorption with photocatalysis to understand their recognition mechanism and the possible interaction between the target molecule and MIPs. Then their common imprinting polymerization processes i.e., free radical polymerization and non-free radical polymerization are briefly discussed with their respective advantages and disadvantages. In addition, this review highlights the photocatalytic degradation mechanism of photocatalyst cum adsorbent is critically discussed by comparing it with non-imprinted polymers. Finally, the applications of M-MIPs in the removal or degradation of refractory pollutants, sensing, and recognition have also been delineated. This paper summarises progressive future challenges of the technology that need to be exploited for the preparation of the targeted catalyst
查看更多>>摘要：The current review discusses the recent advances in Ag-based electrocatalysts for electrocatalytic conversion of CO2 to CO. The comparable electrocatalytic activity, stability, and lower cost of the Ag-based catalysts with that of Au-and Pd-based catalysts make the former commercially more viable for the electrochemical CO2 conversion to CO. The challenges associated with the electrochemical CO production are discussed. The impacts of the surface composition, surface area, particle size, porosity, lattice edge, crystal plane, and the defects on the catalytic activity of the electrocatalyst are also reviewed. CO2 elec-trolysers, especially the membrane electrode assembly (MEA)-based electrolyser and its constituents, are described. The infrastructure of the gas diffusion electrode (GDE) and development thereof was found critical for the microenvironment of the liquid-gas interface near the catalyst surface in a GDE-based system to sustain a higher activity over a period of time still remains a challenge. Hence, pathways to cautiously produce benchmark GDEs are discoursed. The role of different ion-exchange membranes and the associated challenges are reviewed. In the end, perspectives on catalyst design and the electrochemical CO2 reduction (eCO2R) to CO process are given to assist in further improving the electrocatalytic efficiency.
查看更多>>摘要：A variety of polymer-based photocatalysts for the highest photocatalytic activity through various modifications and improvements such as doping, treatment with the oxidising or reducing agent, and integrating another nanomaterial into the polymer photocatalysts composite are extensively studied. Furthermore, the most common issues on polymer-based photocatalysts, including wide band gap and high recombination rate of charge carriers, still need to be improved to yield high photocatalytic activity. Besides hydrogen evolution through the water splitting system, focus also has been paid to photocatalytic for CO2 reduction, photodegradation of pollutants, photocatalytic chemical synthesis, and photocatalytic nitrogen fixation. This review attempts to reveal the secret of properties, issues, and enhancements, principally in polymer photocatalysts, besides highlighting the reason for polymeric material as a critical non-metal-based photocatalyst for various photocatalytic reactions, as well as conducting polymeric material with photocatalytic functionality.
Jayaprina GopalanArchina ButhiyappanAbdul Aziz Abdul Raman
24页
查看更多>>摘要：Recently, biomass has been understood and investigated to develop adsorbents for carbon dioxide (CO2) adsorption due to their non-hazardous nature, availability, low disposal cost, and thermal stability. In this perspective, the sustainable approach of converting biomass into activated carbon (BAC) for the adsorption of CO2 is promising for solid waste management while reducing anthropogenic greenhouse gas emissions. Among other biomass adsorbents, metal oxide impregnated activated carbon (MBAC) has demonstrated excellent adsorption affinity for CO2 adsorption. Therefore, in this review, an evaluation and detailed study of various MBACs for CO2 adsorption is presented for the first time. BAC synthesize method, including various carbonization techniques, surface activation and functionality approaches have been discussed. This study also provides detailed overview of MBAC in the context of various preparation methods, critical factors and operating parameters for a high CO2 adsorption capacity. Besides, the solid-gas reactor configuration, cyclic regeneration techniques, CO2 adsorption process mechanism, and CO2 adsorption kinetics also have been discussed. Finally, concluding remarks and future perspectives for biomass-derived MBAC for CO2 adsorption capture were addressed. This review will also assist in the search for alternatives to CO2 adsorption technology, which is both cost-effective and environmentally friendly.
查看更多>>摘要：In recent years, poly(ionic liquids) or polymerized ionic liquids (PILs) have gained significant attention. The combination of ionic liquids (ILs)' unique properties with the macromolecular architecture of poly (ionic liquids) membranes (PILMs) is not only fascinating, but it also offers a way to develop new properties and functionalities for these innovative membrane materials in the field of membrane technology. Furthermore, PILMs provide a number of advantages over ionic liquids (ILs), including increased mechanical stability, chemical durability, spatial controllability, and processability. This paper presents a comprehensive overview of PILMs, including production processes, properties, and applications in industries such as electrolyte membranes for electrochemical devices, metal ions separation with polymer inclusion membranes (PIMs), CO2 separation, and antibacterial membrane. Additionally, future potential and approaches for improving the performance of PILMs are highlighted.
查看更多>>摘要：Global warming and adverse climate change, which have been intensified by a strident increase in carbon dioxide (CO2) emissions, have necessitated the development of alternative techniques to reduce the disproportionate concentration of CO2 in the atmosphere. The photoelectrochemical reduction of CO2 is a technique of lowering the energy required to convert greenhouse gases into useful end products. Herein, we have manufactured an innovative, cost-effective silver (Ag) decorated anatase TiO2 (TO-Agx; 'x' stands for different concentration of Ag) nanoparticles which created on the 3D nanoporous structured surface of a thin titanium foil (Ti-foil) by the assist of chemical treatment with hydrogen peroxide (H2O2) and different concentrations (1, 5, 10, 20 mM) of silver nitrate (AgNO3) solution and followed by calcination at 500 °C. As-prepared samples were analyzed by several characterization techniques such as XRD, XPS, TEM and Raman spectroscopy. Among various samples (TO, TO-Ag1, TO-Ag5, TO-Ag_(20)), the TO-Ag_(10) sample were exposed a supreme photocurrent density of 83.2 uA/cm~(-2) (86.1% higher than TO sample which is untreated with AgNO3 solution). Because of its high photocurrent density, the sample TO-Ag_(1) were selected as the electrode material for photoelectrochemical CO2 reduction reaction and a lowest reduction onset potential (-1.018 V) was observed on linear sweep voltamme-try analysis in the presence of light with Ag/AgCl reference electrode.~1H NMR analysis of the product solution exposed the production of formic acid as a single product of CO2 reduction reaction after the chronoamperometric electrolysis were carried out more than 6 h. The maximum faradaic efficiency (73%) and formic acid yield (193 pmol cm~(-2) h~(-1)) were found at an applied potential of-1.2 V (vs. Ag/AgCl reference electrode) for TO-Ag_(10) photocathode.
查看更多>>摘要：In this work, vapor-induced phase separation (VIPS) coupled with non-solvent induced gelation phase separation (NIGPS), in which water was used as an additive to tailor loose nanofiltration (NF) membrane, was utilized to obtain an optimized and smoother primer PVDF membrane for efficient dye separation. Next, a polydopamine (PDA) layer was formed through the Mussel-inspired technique on the surface of the as-prepared PVDF membrane. Subsequently, an epoxy-propoxypropyl-trimethoxysilane (EPPTMS) layer was also fabricated on the PDA layer in order to enhance hydrophilicity and rejection performance of the prepared membrane. It was demonstrated that through the addition of external H2O (4%), viscosity was escalated due to the pre-gelation. Moreover, the NIGPS-VIPS process resulted in better consolidation of PVDF chains during de-mixing process, and therefore, led to the improved porosity and surface pore size. After the formation of PDA and EPPTMS layers, extraordinary separation and flux performance were obtained. The permeation rate across the membrane was as high as 15.5 L.m~(-2).h~(-1). bar~(-1), and the rejections of Crystal violet (CV), Methylene blue (MB), Methyl green (MG), Reactive red 120 (RR), and Direct yellow (DY) dye solutions (0.2 g/L) by the prepared PVDF/PDA/EPPTMS membrane were 99.1%, 98.1%, 98.6%, 90.3%, and 97.3%, respectively. Moreover, flux recovery rate was also enhanced from 59.0% to 94.2%, which was about 60% enhancement. The optimum membrane also exhibited an outstanding long-term rejection and long-term flux. All the separation tests demonstrated the extraordinary performance of the optimum membrane for dye rejection applications.
查看更多>>摘要：Sustainable bio-based dialdehyde cellulose (DAC) was employed to transform crystalline urea-formaldehyde (UF) resins into amorphous ones for simultaneouly improving their adhesion strength and formaldehyde emission. Serial samples of the UF resins modified with DAC during the resin synthesis were extracted to understand the chemical reactions between the DAC and UF species. Fourier transform infrared, ~1H-nuclear magnetic resonance (NMR), and ~(13)C NMR spectroscopies confirmed the occurrence of reactions between the DAC and UF species. As the synthesis proceeded, the crystallinity of the modified UF resins decreased from 51.7% to 17.4%, transforming the crystalline domains into amorphous ones. Thermograms showed that the DAC in the modified UF resins was decomposed at temperatures over 200 °C as degraded form, resulting in a lower cross-linking density than that of the neat UF resins. The adhesion strength of the modified UF resins was statistically similar to that of the neat UF resins, and the formaldehyde emission of the modified UF resins dramatically decreased to ~ 64.6%. These results evidence the significant application potential of bio-based DAC in improving the sustainability and performance of UF resins.
查看更多>>摘要：Rapid depletion of non-renewable sources has made us look into possible green energy alternatives to meet energy challenges. Electrocatalytic reactions involving oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) play crucial roles in assisting the derivation of clean forms of energy. Here, we demonstrate that few layers of the manganese oxide: hausmannitene (atomically thin two dimensional (2D-Mn3O4) can be exfoliated from its bulk form hausmannite (Mn3O4). Most significantly, the hausmannitene exhibits catalytic activity towards oxygen reduction and evolution reactions. The hausmannitene has enhanced Mn(III) ions (~65%) compared to its parent structure hausmannite (~31%). The Mn(III) ions in a distorted lattice show the highest catalytic activity towards OER performance with the oxygen electrode activity (AE) of 1.08 eV for hausmannitene. The density functional theory (DFT) calculations, confirmed the presence of both Mn(III) and Mn(II) sites on the (112)-oriented surface of Mn3O4 which are highly active for OER and ORR, having vacant and filled orbitals of lowest and highest energy, respectively. Increased oxidation sites aiding to better performance of 2D structure was theoretically manifested. Therefore, demonstrating that similar mechanisms can be used to explore other 2D oxides as possible efficient stable electrocatalyst substitute for energy conversion.
查看更多>>摘要：Topical administration of minoxidil (MXD) on the skin is a widely used method for the treatment of hair loss. To enhance the efficacy of MXD in human skin, the appendageal route through the hair follicle could be promising. Therefore, we developed MXD-loaded double emulsion nanoparticles (MXD-DE-NPs) using poly (D,L-lactide-co-glycolide; PLGA) and surfactants. The size of MXD-DE-NPs was 137.8 ± 0.814 nm and their encapsulation efficiency of MXD was approximately 43%. The MXD-DE-NPs showed no aggregation in aqueous conditions at 1% w/v MXD concentration without ethanol and propylene glycol. In human follicular dermal papilla cells, the NPs showed fast cellular uptake and no significant toxicity. After treatment on the skin of shaved mice, efficient skin penetration of the NPs could be observed on fluorescence imaging. NP treatment for three weeks resulted in efficient regrowth of hair in mice without ethanol and propylene glycol similar to the traditional MXD formula. These results demonstrated that MXD-DE-NPs are a promising carrier for MXD in the treatment of hair loss.
NSTL