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101.
R. Shanmugam J. Ganesamurthi T.-W. Chen S.-M. Chen M. Balamurugan M.A. Ali A.M. Al-Mohaimeed W.A. Al-onazi K. Alagumalai 《Materials Today Chemistry》2022
Herein, we reported the fabrication of porous iron oxide/carbon black (P–Fe2O3/CB) composite through a two-step engineering method. At first, Prussian blue microcubes were used as a precursor and further calcined to form P–Fe2O3 microcubes. The intercalation of CB nanoparticles with P–Fe2O3 nanocubes was processed through the ultrasonication method. The obtained P–Fe2O3/CB were successfully scrutinized through various physiochemical characterization methods. The proposed P–Fe2O3/CB-modified glassy carbon electrode sensor was successfully implemented in the electrochemical sensing of chlorpromazine hydrochloride due to its very low charge transfer resistance (Rct) compared to the other electrode modifiers. The sensitive detection of CPMH through differential pulse voltammetry exemplifies an excellent electroanalytical performance such as a wide linear range of 0.5–1472 μM, a lower detection limit (0.001 μM), and an appraisable sensitivity of 1.99 μA/μM cm?2 due to its availability of a high number of active sites and its large surface area, respectively. It also expresses excellent selectivity, repeatability, reproducibility, and stability results. Moreover, the practical feasibility of the as-fabricated P–Fe2O3/CB/glassy carbon electrode sensor shows exquisite recovery (98.1–100.8%) results with an appraisable current response in various biological, pharmaceutical, and environmental samples. 相似文献
102.
《Arabian Journal of Chemistry》2022,15(9):104031
Quercus mongolica leaf (QL), an easily available biomass, was used as the precursor for preparing the hierarchical porous carbon with a large specific surface area and high adsorption capacities toward the representative dye and antibiotic. After being carbonized, QL was further chemically activated, and potassium hydroxide was proved to be a better activator than sodium hydroxide. The QL-derived porous carbon (PCQL) exhibited abundant micro- and mesopores, and the specific surface area reached 3275 m2 g?1. The performances of PCQL were evaluated through adsorbing rhodamine B (RhB) and tetracycline hydrochloride (TC) from water. Four adsorption isotherm models (the Langmuir, Freundlich, Sips, and Redlich-Peterson models), three adsorption kinetic models (the pseudo-first-order, pseudo-second-order, and intra-particle diffusion models), and the thermodynamic equations were used to investigate the adsorption processes. The pseudo-second-order kinetic model and the Sips isotherm model fitted the experimental data well, which indicates that the adsorption processes were controlled by the amount of adsorption active sites on the surface of PCQL, and these adsorption active sites had different affinities for the adsorbates. The maximum adsorption capacities of PCQL toward RhB and TC were 1946.0 and 1479.6 mg g?1, respectively, based on the Sips model. The thermodynamic analysis indicates that the adsorption of PCQL toward adsorbents was spontaneous physical processes accompanied by the increasing disorder degree. The adsorption mechanism was attributed to the combination of the pore-filling, hydrogen bond, and π-π interactions. Moreover, in the fixed-bed experiments, the Yoon-Nelson model fitted the breakthrough curves well, and about 8 L wastewater containing RhB (200 mg L?1) may be effectively treated by 1.0 g of PCQL. Above results indicate that QL is a promising precursor for preparing functional porous carbon materials. 相似文献
103.
A highly sensitive amperometric galactose biosensor was developed by encapsulating galactose oxidase within the graphene-doped sol-gel titania-Nafion composite film on platinized glassy carbon electrode. Due to the combined electrocatalytic activity of graphene and Pt NPs on the electrode towards hydrogen peroxide as well as the mesoporous nature of the titania-Nafion composite, the present galactose biosensor exhibited relatively fast response time under 2 s, high sensitivity of 40.6 mAM−1cm−2, and wide dynamic range over three orders of magnitude with a detection limit of 3.78×10−6 M (S/N=3). In addition, the biocompatible composite in the biosensor secures excellent long-term stability. 相似文献
104.
A low-temperature spray deposition synthesis was developed to prepare locally hexagonally ordered mesoporous titania films with polycrystalline anatase pore walls in an evaporation-induced self-assembly process. The titania film preparation procedure is conducted completely at temperatures below 50 °C. The effects of spray time, film thickness, synthesis time prior to spray deposition, and aging time at high relative humidity after deposition on the atomic arrangement and the mesoorder of the mesoporous titania were studied. We find the crystallite size to depend on both the synthesis time and aging time of the films, where longer times result in larger crystallites. Using the photocatalytic activity of titania, the structure-directing agent is removed with UV radiation at 43–46 °C. The capability of the prepared films to remove the polymer template increased with longer synthesis and aging times due to the increased crystallinity, which increases the photocatalytic efficiency of the titania films. However, with increasingly longer times, the crystallites grow too large for the mesoorder of the pores to be maintained. This work shows that a scalable spray coating method can be used to prepare locally ordered mesoporous polycrystalline titania films by judiciously tuning the synthesis parameters. 相似文献
105.
以三苯胺为单体, 无水三氯化铁为催化剂, 二甲醇缩甲醛为外交联剂, 通过机械球磨不同比例的三苯胺、 三氯化铁和二甲醇缩甲醛, 合成了PAF-106s(PAF-106a~PAF-106c, PAF: porous aromatic framework). 红外光谱、 元素分析、 X射线光电子能谱和固体核磁共振波谱等表征结果证明发生了聚合反应. 氮气吸附结果表明, 三苯胺、 三氯化铁和二甲醇缩甲醛的比例影响PAF-106s的多孔性能. 三氯化铁和三苯胺摩尔比从3∶1增加到12∶1时, PAF-106c的BET比表面积从PAF-106a的135 m2/g增加到280 m2/g. 引入二甲醇缩甲醛后, PAF- 106d~PAF-106g的BET比表面积随三氯化铁和二甲醇缩甲醛摩尔比的增加而逐渐降低. 在273和298 K下, 测试了PAF-106c的C2烃吸附性能, 并采用理想吸附溶液理论计算了C2H2/C2H4和C2H6/C2H4分离比. 相似文献
106.
107.
108.
The Incorporation of Titania into Modified Silicates for Solar Photodegradation of Aqueous Species 总被引:2,自引:0,他引:2
Lowell R. Matthews David Avnir Alexander D. Modestov Srinivasan Sampath Ovadia Lev 《Journal of Sol-Gel Science and Technology》1997,8(1-3):619-623
A new class of sol-gel-derived photocatalytic materials has been synthesized and used in solar-assisted photodegradation studies. The materials are comprised of a homogeneous dispersion of commercial TiO2 powder into silica and organically modified silicate (Ormosil) hosts. The efficiency of the photocatalytic properties of these TiO2-containing materials was determined by their relative performance in the solar photodecomposition of aqueous rhodamine B. The improved adsorption properties of the modified materials compared to commercial TiO2 increase the photodecomposition rate and the buoyancy properties, although excess hydrophobicity decreases the wetted section of the catalyst and its photocatalytic performance. These materials can be used as floatable catalysts for solar-assisted water purification. 相似文献
109.
K. E. Collins M. L. M. M. Granja R. G. Pereira Filho T. A. Anazawa I. C. S. F. Jardim 《Chromatographia》1997,45(1):99-103
Summary Poly(methyloctylsiloxane) (PMOS), sorbed into the pores of HPLC silica particles by solvent evaporation, can function as a
useful stationary phase for reversed-phase chromatography. The present work addresses the question of how the PMOS is distributed
in the pores. Measurements of the surface area (BET, N2) of a series of partially loaded samples (0–40% PMOS, m/m) using a typical batch of HPLC silica (10 μm irregular particles
with 6 nm pores) show that the specific surface area of the samples decreases linearly with the specific loading (mass of
PMOS per gram of silica). This result is not consistent with a “film” model in which the PMOS is deposited uniformly on the
pore walls, but is consistent with a model in which long segmented “plugs” of PMOS are deposited within the pore system.
Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996 相似文献
110.
Since the outbreak of the COVID-19 pandemic, most countries have recommended their citizens to adopt social distance, hand hygiene, and face mask wearing. However, wearing face masks has not been well adopted by many citizens. While the reasons are complex, there is a general perception that the evidence to support face mask wearing is lacking, especially for the general public in a community setting. Face mask wearing can block or filter airborne virus-carrying particles through the working of colloid and interface science. This paper assesses current knowledge behind the design and functioning of face masks by reviewing the selection of materials, mask specifications, relevant laboratory tests, and respiratory virus transmission trials, with an overview of future development of reusable masks for the general public. This review highlights the effectiveness of face mask wearing in the prevention of COVID-19 infection. 相似文献