969 results on '"nanocatalysis"'
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2. 以茴香脑为原料的纳米催化合成对甲氧基肉桂醛的研究 --推荐一个本科生科研竞赛项目
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李姝慧, 谭丹, 武芸杞, 唐海涛, 何权洲, 贾均松, and 潘英明
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CHEMISTRY students , *SCIENCE education , *PLANT extracts , *NANOPARTICLES , *COLLEGE students - Abstract
In alignment with the national strategy for rejuvenating the country through science and education and strengthening the nation through talent development, Guangxi Normal University has actively implemented the "College Students' Innovation and Entrepreneurship Training Plan". This paper presents a case study of an undergraduate team at Guangxi Normal University that independently researched and synthesized a novel porous nanocatalyst. They successfully employed this catalyst in a green and environmentally friendly process to synthesize high-purity p-methoxycinnamaldehyde from the natural plant extract anethole. The team participated in the "Internet Plus" innovation and entrepreneurship competition and the "Challenge Cup" extracurricular academic science and technology works competition. This paper outlines the project preparation, research and development process, and practical outcomes, with the aim of sharing the team's experiences with other chemistry students to facilitate more efficient completion of research competition projects. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Hydrogenolysis of Bio-Glycerol over In Situ Generated Nanosized Cu-ZnO Catalysts.
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Porukova, Iuliana, Samoilov, Vadim, Lavrentev, Vladimir, Ramazanov, Dzhamalutdin, and Maximov, Anton
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CATALYST selectivity , *CATALYST structure , *METAL catalysts , *ETHYLENE glycol , *LACTIC acid - Abstract
Due to the growth of biodiesel production, utilization of the glycerol formed as a by-product is still of considerable importance. This study is devoted to a novel approach for glycerol hydrogenolysis with use of in situ generated Cu-ZnO catalysts. The main product formed is 1,2-propanediol, with the by-products being lactic acid and ethylene glycol. The Cu-ZnO catalysts are characterized by AAS, XRD, XPS, SEM, TEM, EDX, BET, and chemisorption N2O. The proportion of ZnO turns out to have a significant effect on the activity and selectivity of the catalyst formed. Increasing the ZnO content enables one to obtain more dispersed, active, selective, and agglomeration-resistant catalysts. The transition from monometallic Cu catalysts to Cu-ZnO with a ZnO content of 65 wt% allows one to increase selectivity from 74 to 86%, TOF from 0.136 to 0.511 s−1, and SCu from 1.9 to 7.1 m2/g-Cu. The morphology of the synthesized Cu-ZnO catalysts resembles the structure of oxide/metal inverse catalysts. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Solid‐State NMR of Heterogeneous Catalysts.
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Haro Mares, Nadia, Logrado, Millena, Kergassner, Jan, Zhang, Bingyu, Gutmann, Torsten, and Buntkowsky, Gerd
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POLARIZATION (Nuclear physics) , *HETEROGENEOUS catalysis , *HETEROGENEOUS catalysts , *NUCLEAR magnetic resonance , *COORDINATION polymers , *SILICA gel , *CHEMICAL shift (Nuclear magnetic resonance) - Abstract
Recent advances in solid‐state nuclear magnetic resonance (NMR) spectroscopy, combined with dynamic nuclear polarization (DNP), quantum chemical DFT calculations, and gas‐phase NMR spectroscopy investigating the structure and reactivity of heterogeneous catalysts are reviewed. The investigated catalysts range from classical mononuclear catalysts, like immobilized derivates of Wilkinson's catalysts over binuclear catalysts such as the dirhodium paddlewheel catalyst to catalytic nanoparticles, employing various support materials, such as mesoporous silica gels, coordination polymers, and biomaterials such as cellulose. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Reduction of 4‐Nitrophenol Catalyzed by Gold Nanoclusters with Aggregation‐Induced‐Emission: Emission Intensity Correlated Activity and Mechanistic Exploration.
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Peng, Bo, Shan, Bingqian, Lam, Koonfung, and Zhang, Kun
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CHEMICAL kinetics , *GOLD clusters , *CATALYTIC activity , *LIGANDS (Chemistry) , *HYDROGEN bonding , *GOLD catalysts - Abstract
Thiolate‐protected Au nanoclusters (NCs) have developed as a promising class of model catalysts to achieve fundamental understanding of metal nanocatalysis. Whereas, the packing mode of peripheral ligand on metal core is changeful in the reaction medium and show elusive impact on catalytic activity. In this work, using glutathione (GSH) protected Au NCs (Au@GSH NCs) with aggregation‐induced‐emission (AIE) characteristics as model catalyst for the hydrogenation of 4‐nitrophenol (4‐NP), photoluminescence (PL) intensity correlated catalytic activity of Au@GSH NCs was successfully mediated by the addition of Ag+ in the preparation or poor solvent in the reaction medium, showing a relationship of “as one falls, another rises.” Au NCs with intense PL implied a dense packing of peripheral ligand, which hampered the accessibility of active site and thus exhibited slowest catalytic reaction kinetics of the reduction of 4‐NP and vice versa. Based on this methodology, a case study of the effect of salt additives on the catalytic activity is carried out, different mechanisms are distinguished by the change in the PL intensity, and with the combination of diagnostic deuterium isotope experiments, it has been demonstrated that the proton from water solvent is involved in the reaction and that the proton transfer process is the rate‐determining step, the contribution of ionic additives to the hydrogen bonding network determines their effect on the reaction kinetics. The correlation between PL intensity and catalytic activity of Au NCs could provide an efficient way to design highly active Au NC catalysts and give a new insight to understand the unique optoelectronic properties of Au NCs and reaction mechanism. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Cobalt-manganese bimetallic organic frameworks catalyzed solvent-free oxidation of benzyl C-H bonds with O2 as sole oxidant.
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Cao, Ke, Zhou, Yan, Lv, Shanshan, Feng, Mengmeng, Qian, Changjin, and Chen, Zheng
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ACTIVATION energy ,OXIDATION states ,CATALYTIC oxidation ,KETONES ,CHARGE exchange ,ALCOHOL oxidation - Abstract
The selective oxidation of hydrocarbons can be used to produce oxygen-containing functional compounds such as alcohols, aldehydes or ketones and its efficient and green conversion lies in the development of efficient catalysts that activate C-H bonds and O
2 simultaneously. In this work, the bimetallic organic framework (CoMnBDC) material with morphology of stacked nanosheets was synthesized using terephthalic acid as ligands to coordinate with Co2+ and Mn2+ cations under solvothermal conditions. As revealed by spectroscopic characterizations, the electron transfer from Mn to Co in the CoMnBDC resulted in the reduction of the Co average oxidation state and increase of the Mn average oxidation state. The CoMnBDC nanosheets were used as catalyst in catalytic oxidation of ethylbenzene, in which the redox effect promotes the effective electron transfer, the activation of O2 and benzyl C-H bond. The 96.2% conversion of ethylbenzene and 98.0% selectivity towards acetophenone could be obtained with oxygen as sole oxidant and solvent-free condition. The excellent catalytic performance is related to the structure of CoMnBDC and is also the best when compared with reported results. Various types of aromatic hydrocarbons containing benzyl C-H bonds can be effectively oxidized by CoMnBDC to produce corresponding ketone products. The density functional theory (DFT) calculation revealed that the redox effect leads to the relative enrichment of electrons on Co in CoMnBDC, which is conducive to the activation of O2 ; Mn with higher oxidation state is beneficial for the adsorption of ethylbenzene and activation of C-H bonds. The CoMnBDC has a lower energy barrier for transition state, making it easier for the ethylbenzene oxidation to produce acetophenone. [ABSTRACT FROM AUTHOR]- Published
- 2024
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7. TME-Activated MnO2/Pt Nanoplatform of Hydroxyl Radical and Oxygen Generation to Synergistically Promote Radiotherapy and MR Imaging of Glioblastoma
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Chen L, Liu M, Wang Y, Wei W, Li Y, Bai Y, Yu X, Jiao L, and Wang M
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radiotherapy ,glioblastoma ,mno2/pt@bsa nanoplatform ,nanocatalysis ,Medicine (General) ,R5-920 - Abstract
Lijuan Chen,1,* Mingbo Liu,2,* Yunjuan Wang,3,4,* Wei Wei,1 Yaqiong Li,5 Yan Bai,1 Xuan Yu,1 Lei Jiao,6 Meiyun Wang1,4 1Department of Medical Imaging, Henan Provincial People’s Hospital & the People’s Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, People’s Republic of China; 2Department of Radiotherapy, Henan Provincial People’s Hospital & the People’s Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, People’s Republic of China; 3School of Life Sciences, Henan University, North Section of Jinming Avenue, Kaifeng, Henan, 475004, People’s Republic of China; 4Institute of Biomedicine, Henan Academy of Sciences, Zhengzhou, Henan, 450046, People’s Republic of China; 5Department of Pharmacy, Henan Provincial People’s Hospital & the People’s Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, People’s Republic of China; 6Institute of Molecular Metrology, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao, Shandong, 266071, People’s Republic of China*These authors contributed equally to this workCorrespondence: Meiyun Wang, The Department of Medical Imaging, Henan Provincial People’s Hospital & the People’s Hospital of Zhengzhou University, No. 7, WeiWu Road, Zhengzhou, Henan, 450003, People’s Republic of China, Email mywang@zzu.edu.cnPurpose: Radiotherapy (RT) is currently recognized as an important treatment for glioblastoma (GBM), however, it is associated with several challenges. One of these challenges is the radioresistance caused by hypoxia, whereas the other is the low conversion efficiency of the strongly oxidized hydroxyl radical (•OH), which is produced by the decomposition of water due to high-energy X-ray radiation. These factors significantly limit the clinical effectiveness of radiotherapy.Results: To address these limitations, we developed a highly stable and efficient nanoplatform (MnO2/Pt@BSA). Compared to MnO2@BSA, this platform demonstrates high stability, a high yield of oxygen (O2), enhanced production of •OH, and reduced clearance of •OH. The system exhibited increased O2 production in vitro and significantly improved oxygen production efficiency within 100 s at the Pt loading of 38.7%. Furthermore, compared with MnO2, the expression rate of hypoxia-inducible factor (HIF-1α) in glioma cells treated with MnO2/Pt decreased by half. Additionally, the system promotes •OH generation and consumes glutathione (GSH), thereby inhibiting the clearance of •OH and enhancing its therapeutic effect. Moreover, the degradation of the nanoplatform produces Mn2+, which serves as a magnetic resonance imaging (MRI) contrast agent with a T1-weighted enhancement effect at the tumor site. The nanoplatform exhibited excellent biocompatibility and performed multiple functions related to radiotherapy, with simpler components. In U87 tumor bearing mice model, we utilized MnO2/Pt nanocatalysis to enhance the therapeutic effect of radiotherapy on GBM.Conclusion: This approach represents a novel and effective strategy for enhancing radiotherapy in gliomas, thereby advancing the field of catalytic radiotherapy and glioma treatment.Keywords: radiotherapy, glioblastoma, MnO2/Pt@BSA nanoplatform, nanocatalysis
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- 2024
8. Atomically dispersed iron sites from eco-friendly microbial mycelium as highly efficient hydrogenation catalyst.
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Kuang, Junhua, Zhang, Shuaishuai, Yu, Jia, Zhang, Yuting, Peng, Chun-Kuo, Zou, Chen, Li, Jiaran, Peng, Li, Lin, Lu, Lin, Yan-Gu, Lyu, Pengbo, Yang, Shuliang, and Li, Jian-Feng
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SUSTAINABLE chemistry , *CARBON-based materials , *HETEROGENEOUS catalysts , *ACTIVATION energy , *CATALYTIC activity , *IRON catalysts , *NITROALDOL reactions , *POROUS polymers , *IRON clusters - Abstract
Through leveraging the abundant functional groups in fungi to effectively coordinate with metal ions, and incorporating the additional nitrogen species provided by the in situ encapsulated ZIFs shell layer, an iron single-atom catalyst Fe-TA@ZIF with an asymmetric Fe 1 -N 3 P 1 coordination structure was engineered, which exhibited impressive catalytic performance in the selective hydrogenation of nitroaromatics to anilines. [Display omitted] Iron, one of the most abundant elements on earth and an essential element for living organisms, plays a crucial role in our daily metabolism. In the field of catalysis, the development of high-performance catalysts based on less toxic iron element is also of significant importance for green chemistry and a sustainable future. To construct Fe-based heterogeneous catalysts with excellent hydrogenation performance, precise modulation of the atomic coordination structure is a key strategy for enhancing catalytic activity. In this study, we present an in-situ coating method for applying a zeolitic imidazolate framework (ZIF) onto the surface of fungal hyphae. The asymmetric coordination structure of Fe 1 -N 3 P 1 was precisely tailored by utilizing the phosphorus source from the fungus and the nitrogen source in the ZIFs. Detailed characterizations and density functional theory calculations revealed that the incorporation of ZIFs not only increased the specific surface area of catalysts, but also facilitated the dispersion of Fe 2 P nanoparticles into the Fe 1 -N 3 P 1 center, making the lowest reaction energy barrier and resulting in the best performance for nitrobenzene hydrogenation when compared to the Fe 2 P nanoparticles and clusters. This research introduces a novel design concept for constructing asymmetric monoatomic configuration based on the inherent characteristics of natural microorganisms and the exogenous porous coordination polymers. [ABSTRACT FROM AUTHOR]
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- 2025
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9. Ceria nanocatalyst-supported oxidative organic transformations of aromatic alcohols and p -nitrotoluene.
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Naaz, Farha, Alshehri, Saad M, and Ahmad, Tokeer
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TOLUENE , *CERIUM oxides , *FOURIER transform infrared spectroscopy , *ALCOHOL oxidation , *THERMOGRAVIMETRY , *PARTIAL oxidation , *X-ray photoelectron spectroscopy - Abstract
Hydrothermally derived nanocubes of CeO2 (10 nm) were explored as an efficient heterogeneous catalyst in the partial oxidation of aromatic alcohols to the corresponding aldehydes and aerobic oxidation of p -nitrotoluene to p -nitrobenzoic acid. The CeO2 nanocatalyst was characterized by x-ray diffraction, transmission electron microscopy (TEM), energy dispersive spectroscopy, x-ray photoelectron spectroscopy, Brunauer–Emmett–Teller (BET) surface area analysis, Fourier transform infrared spectroscopy, thermal gravimetric analysis and ultraviolet–visible spectroscopy. TEM/high-resolution TEM micrographs reveal a morphology of mostly cubic nanostructures with exposed highly active {100} and {110} facets. The surface area of nanoceria was determined by BET analysis and found to be 33.8 m2 g−1. To demonstrate the universality of the catalytic system, the selective oxidation of different substrates of benzylic alcohol and complete oxidation of p -nitrotoluene was investigated under mild conditions. Absolute selectivity towards their respective aldehydes was found to be 99.50% (benzaldehyde), 90.18% (p -chlorobenzaldehyde), 99.71% (p -nitrobenzaldehyde), 98.10% (p -fluorobenzaldehyde), 94.66% (p -anisaldehyde) and 86.14% (cinnamaldehyde). Moreover, the catalytic oxidative transformation of nitrotoluene results in 100% conversion with 99.29% selectivity towards nitrobenzoic acid. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Waste-Derived Caffeine for Green Synthesis of Rhenium Nanoparticles with Enhanced Catalytic Activity in the Hydrogenation of 4-Nitrophenol.
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Kuś, Alicja, Leśniewicz, Anna, Dzimitrowicz, Anna, Pohl, Pawel, and Cyganowski, Piotr
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COFFEE grounds , *COFFEE waste , *X-ray powder diffraction , *COFFEE beans , *CATALYTIC hydrogenation - Abstract
Yearly, thousands of tons of wasted coffee grounds are produced according to high coffee consumption. Still, after the coffee brewing, wasted coffee grounds contain some amounts of caffeine (CAF). CAF, in turn, contains multiple O and N chelating atoms in its structure. These have a potential to be reductors for complexes of metals. In this context, within the present study, a set of CAF extracts derived from coffee beans and coffee grounds were obtained and then used for the one-step reduction of ReO4− ions with no additional toxic chemicals. Within this approach, CAF was applied as a secondary, green resource for the synthesis of unique rhenium nanoparticles (ReNPs) containing Re species at 0 and +6 oxidation states. The obtained ReNPs were identified and characterized with the use of X-ray powder diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). Further, the capping and stabilization of ReNPs by CAF were verified with the aid of Fourier transformation infrared spectroscopy (FT-IR). The so-obtained "green" ReNPs were then used as a homogenous catalyst in the catalytic hydrogenation of 4-nitrophenol (4-NP). This new nanomaterial revealed a superior catalytic activity, leading to the complete reduction of 4-NP to 4-aminophenol within 40–60 min with a first-order rate constant of 0.255 min−1. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Electrospun Smart Hybrid Nanofibers for Multifaceted Applications.
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Nirwan, Viraj P., Amarjargal, Altangerel, Hengsbach, Rebecca, and Fahmi, Amir
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TECHNOLOGICAL innovations , *NANOSTRUCTURED materials , *ELECTROTEXTILES , *HYBRID materials , *NANOFIBERS , *SMART materials - Abstract
Smart electrospun hybrid nanofibers represent a cutting‐edge class of functional nanostructured materials with unique collective properties. This review aims to provide a comprehensive overview of the applications of smart electrospun hybrid nanofibers in the fields of energy, catalysis, and biomedicine. Electrospinning is a powerful tool to fabricate different types of nanofibers’ morphologies with precise control over structure and compositions. Through the incorporation of various functional components, such as nanoparticles, nanomoieties, and biomolecules, into the (co)polymer matrix, nanofibers can be tailored into smart hybrid materials exhibiting responsiveness to external stimuli such as temperature, pH, or light among others. Herein recent advancements in fabrication strategies for electrospun smart hybrid nanofibers are discussed, focusing on different electrospinning tools aimed at tailoring and developing smart hybrid nanofibers. These strategies include surface functionalization, doping, and templating, which enable fine‐tuning of mechanical strength, conductivity, and biocompatibility. The review explores the challenges and recent progress in the development of smart hybrid nanofibers. Issues such as scalability, reproducibility, biocompatibility, and environmental sustainability are identified as key for improvement. Furthermore, the applications of smart nanofibers in biomedicine, environment, energy storage, and smart textiles underscore their potential to address the challenges in development of nanostructured materials for emerging technologies. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Highly Stable Carboranyl Ligated Gold Nano‐Catalysts for Regioselective Aromatic Bromination.
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Wang, Mengyue, Zhang, Shengye, Gong, Yue, Zhang, Wangyang, Wang, Yu, Chen, Yupeng, Zheng, Qiang, Liu, Zhipan, and Tang, Cen
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GOLD nanoparticles , *HETEROGENEOUS catalysis , *BROMINATION , *GOLD , *ETCHING reagents - Abstract
Achieving electronic/steric control and realizing selectivity regulation in nanocatalysis remains a formidable challenge, as the dynamic nature of metal‐ligand interfaces, including dissolution (metal leaching) and structural reconstruction, poses significant obstacles. Herein, we disclose carboranyls (CBs) as unprecedented carbon‐bonded functional ligands (Eads.CB‐Au(111)=−2.90 eV) for gold nanoparticles (AuNPs), showcasing their exceptional stabilization capability that is attributed by strong Au−C bonds combined with B−H⋅⋅⋅Au interactions. The synthesized CB@AuNPs exhibit core(Aun)‐satellite(CB2Au−) structure, showing high stability towards multiple stimuli (110 °C, pH=1–12, thiol etchants). In addition, different from conventional AuNP catalysts such as triphenylphosphine (PPh3) stabilized AuNPs, dissolution of catalytically active gold species was suppressed in CB@AuNPs under the reaction conditions. Leveraging these distinct features, CB@AuNPs realized outstanding p : o selectivities in aromatic bromination. Unbiased arenes including chlorobenzene (up to >30 : 1), bromobenzene (15 : 1) and phenyl acrylate were examined using CB@AuNPs as catalysts to afford highly‐selective p‐products. Both carboranyl ligands and carboranyl derived counterions are crucial for such regioselective transformation. This work has provided valuable insights for AuNPs in realizing diverse regioselective transformations. [ABSTRACT FROM AUTHOR]
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- 2024
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13. A Copper/Ferrous‐Engineering Redox Homeostasis Disruptor for Cuproptosis/Ferroptosis Co‐Activated Nanocatalytic Therapy in Liver Cancer.
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Zhang, Xiaoling, Zhu, Jiuxin, Wang, Sihao, Li, Siyi, E, Jiaoting, Hu, Jiahe, Mou, Ruishu, Ding, He, Yang, Piaoping, and Xie, Rui
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PHOTOTHERMAL effect , *OXIDATIVE stress , *PRUSSIAN blue , *REACTIVE oxygen species , *SYNTHETIC enzymes - Abstract
Cuproptosis and ferroptosis hold great promise for overcoming apoptotic resistance in liver cancer based on their unique metal‐driven cell death modalities. However, insufficient intracellular copper and iron concentration, complicated tumor microenvironment (TME), and unclear cross‐regulatory mechanisms between cuproptosis and ferroptosis, severely restrict the therapeutic performance. Herein, copper‐doped hollow Prussian blue (CHP) nanozymes are rationally designed for loading photosensitizer indocyanine green (ICG) and O2‐saturated perfluorohexane (PFH), denoted as O2‐PFH@CHPI nanoparticles, to induce cuproptosis and ferroptosis. In response to the specific TME, the CHP nanozymes can synergistically catalyze Fenton reactions and consume endogenous glutathione, leading to the accumulation of reactive oxygen species. Upon near‐infrared irradiation, the O2‐PFH@CHPI‐enabled photothermal effect can simultaneously accelerate catalytic reactions and trigger O2 release for photodynamic therapy to promote oxidative stress. Notably, cuproptosis can be effectively activated through Cu+‐mediated dihydrolipoamide S‐acetyltransferase aggregation and Fe–S cluster protein loss. Concurrently, the tilt of redox balance is favorable for lipid peroxidation and glutathione peroxidase 4 inactivation, resulting in an augmented ferroptosis effect. Mechanistically, oxidative stress‐boosted cuproptosis and ferroptosis jointly disrupt mitochondrial metabolism, which in turn exacerbates intracellular oxidative stress, thus realizing a mutually enhanced therapeutic effect. This work may provide new guidance for utilizing copper/ferrous‐engineering nanozymes for cuproptosis/ferroptosis synergetic therapy. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Cu@CuFe2O4 nanoparticles catalyzed oxidative functionalization of alkynes: Access to α,α‐dichloro ketones.
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Wang, Huahui, Wu, Sichao, Zeng, Xianghua, and Chen, Lu
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NANOPARTICLES , *KETONES , *HETEROGENEOUS catalysts , *ALKYNES , *MAGNETIC nanoparticles , *ARYLATION ,CATALYSTS recycling - Abstract
In this study, novel Cu@CuFe2O4 nanoparticles were prepared by virtue of a simple method. By utilizing a compatible system involving N‐chlorosuccinimide (NCS) as the chlorine source and Cu@CuFe2O4 magnetic nanoparticles (NPs) as recyclable catalyst, we present a novel and practical method for directly obtaining aryl α,α‐dichloroketones in aqueous trifluoroethanol (TFE). The catalyst was recovered and reused up to five times with no significant decrease in activity. The current study provides a foundational raw material for the subsequent synthesis of chlorinated functional molecules, which is achieved through a mild transformation of arylalkynes using readily available commercial feedstocks and exhibiting good tolerance with various substituents on the aromatic ring, including the aliphatic alkyne. This novel heterogeneous catalyst may be used in numerous industrial applications because of its merits, such as considerable recyclability, low requirement for catalyst loading, cost‐effectiveness, and ease of handling. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Cobalt-manganese bimetallic organic frameworks catalyzed solvent-free oxidation of benzyl C-H bonds with O2 as sole oxidant
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Cao, Ke, Zhou, Yan, Lv, Shanshan, Feng, Mengmeng, Qian, Changjin, and Chen, Zheng
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- 2024
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16. Recent Advances in the Use of Controlled Nanocatalysts in Methane Conversion Reactions
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Felipe Anchieta e Silva and Thenner Silva Rodrigues
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methane conversion ,controlled nanomaterials ,nanocatalysis ,Biochemistry ,QD415-436 ,Geophysics. Cosmic physics ,QC801-809 - Abstract
This study investigates the utilization of controlled nanocatalysts in methane conversion reactions, addressing the pressing need for the efficient utilization of methane as a feedstock for valuable chemicals and clean energy. The methods employed include a comprehensive review of recent advancements in nanocatalyst synthesis, characterization, and application, as well as the critical analysis of underlying mechanisms and controversies in methane activation and transformation. The main findings reveal significant progress in the design and synthesis of controlled nanocatalysts, enabling enhanced activity, selectivity, and stability in methane conversion reactions. Moreover, the study highlights the importance of resolving controversies surrounding metal–support interactions for rational catalyst design. Overall, the study underscores the pivotal role of nanotechnology in shaping the future of methane utilization and sustainable energy production, providing valuable insights for guiding future research directions and technological developments in this field.
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- 2024
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17. Starch-supported cuprous iodide nanoparticles catalysed C–C bond cleavage: use of carbon-based leaving groups for bisindolylmethane synthesis.
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Suresh, Muthiah, Singh, Raj Bahadur, Katlakunta, Sadhana, Patra, Snigdha Rani, Tanwer, Yogesh Bhaskar Singh, Mallick, Sadhucharan, Bhunia, Sabyasachi, and Das, Debjit
- Abstract
A starch-supported cuprous iodide nanoparticles (CuI-NPs@starch) catalysed C–C bond cleaving reaction involving carbon-based leaving groups like malononitrile, ethyl cyanoacetate, acetylacetone, and Meldrum's acid has been developed under moisture and air insensitive conditions. This competent C–C bond cleavage reaction is studied in detail as an attractive alternative method to synthesize biologically relevant bisindolylmethanes in moderate to good yields. The CuI-NPs@starch are synthesized in aqueous medium and characterized by X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy studies. [ABSTRACT FROM AUTHOR]
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- 2024
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18. Recent Advances in the Use of Controlled Nanocatalysts in Methane Conversion Reactions.
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e Silva, Felipe Anchieta and Rodrigues, Thenner Silva
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FEEDSTOCK ,METHANE ,NANOTECHNOLOGY ,SUSTAINABLE development ,FUTURES studies - Abstract
This study investigates the utilization of controlled nanocatalysts in methane conversion reactions, addressing the pressing need for the efficient utilization of methane as a feedstock for valuable chemicals and clean energy. The methods employed include a comprehensive review of recent advancements in nanocatalyst synthesis, characterization, and application, as well as the critical analysis of underlying mechanisms and controversies in methane activation and transformation. The main findings reveal significant progress in the design and synthesis of controlled nanocatalysts, enabling enhanced activity, selectivity, and stability in methane conversion reactions. Moreover, the study highlights the importance of resolving controversies surrounding metal–support interactions for rational catalyst design. Overall, the study underscores the pivotal role of nanotechnology in shaping the future of methane utilization and sustainable energy production, providing valuable insights for guiding future research directions and technological developments in this field. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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19. Single Ti atoms coupled with Ti–O clusters enable low temperature hydrogen cycling by sodium alanate.
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Ren, Zhuang-He, Zhang, Xin, Zhang, Wen-Xuan, Huang, Zhen-Guo, Yang, Li-Mei, Yang, Ya-Xiong, Li, Zheng-Long, Li, Juan, Sun, Wen-Ping, Gao, Ming-Xia, Pan, Hong-Ge, and Liu, Yong-Feng
- Abstract
Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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20. Electron Orbital Hybridization‐Enhanced Copper‐Nanocatalysis for Anti‐Infection.
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Luo, Yao, Ruan, Zesong, Guo, Zhao, Chen, Yunfeng, Lin, Han, Ge, Min, and Zhu, Chen
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ORBITAL hybridization , *COPPER , *DRUG resistance in bacteria , *BACTERIAL diseases , *ELECTRONS , *MICROBIAL fuel cells - Abstract
Recurrent bacterial infections, impenetrable microbial biofilms, and irremediable antibiotic resistance are the most perilous threats in orthopedic implant‐associated infections (IAIs). Recently, chemodynamic therapy (CDT) has been considered a promising therapy, while the clinical practices for existing CDT agents are limited by the low therapeutic efficiency in physiological circumstances. Herein, it is demonstrated that silica‐copper nanosheets (Si@Cu NSs) exhibit a combined therapeutic photothermal‐chemodynamic strategy for IAIs treatment with superior capacity and biocompatibility. This unique design endows the nanostructure with enhanced copper‐based Fenton‐like properties via p‐d orbital hybridization by incorporating copper nanoclusters (Cu NCs) on silicene nanosheets (Si NSs) matrix, integrating inherent photothermal performance of Si NSs with specific catalytic anti‐infection of Cu NCs against planktonic bacteria and biofilms both in vitro and in vivo. This study not only reveals the promising bio‐application prospects of 2D nanocatalytic biomaterials but also demonstrates the feasibility of constructing novel CDT agents by orbital hybridization for the catalytic treatment of IAIs. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Metal Nanoparticles on Polymeric Membranes Applied in Catalytic Hydrogenations
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Pich, Rosa, Lahitte, Jean-François, Remigy, Jean-Christophe, Pla, Daniel, Gómez, Montserrat, Beller, Matthias, Series Editor, Dixneuf, Pierre H., Series Editor, Dupont, Jairton, Series Editor, Fürstner, Alois, Series Editor, Glorius, Frank, Series Editor, Gooßen, Lukas J., Series Editor, Nolan, Steven P., Series Editor, Okuda, Jun, Series Editor, Oro, Luis A., Series Editor, Willis, Michael, Series Editor, Zhou, Qi-Lin, Series Editor, and Martínez-Prieto, Luis M., editor
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- 2024
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22. Agro-Wastes-Based Feedstock as a Source for Bionanomaterials Production: Outcomes and Challenges
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Sankaranarayanan, Pooja, Anboli, T. A., Suchithra, T. V., Patra, Jayanta Kumar, Series Editor, Das, Gitishree, Series Editor, Bose, Sankhadip, editor, Shukla, Amritesh Chandra, editor, Baig, Mirza R., editor, and Banerjee, Sabyasachi, editor
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- 2024
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23. Nanocatalytic treatment of oral squamous cell carcinoma Cal 27 cells in vitro based on single-atom iron nanocatalysts.
- Author
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XIE Yu-ting and XIONG Ping
- Published
- 2024
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24. Ultrasmall Ruthenium Nanoclusters Anchored on Thiol-Functionalized Metal–Organic Framework as a Catalyst for the Oxygen Evolution Reaction.
- Author
-
Mishra, Biswajit, Biswal, Swayamprakash, and Tripathi, Bijay P.
- Abstract
The rational design of an efficient nanocatalyst is pivotal for catalyzing kinetically sluggish oxygen evolution reaction (OER). However, the uncontrolled nucleation and growth of nanostructures present significant challenges in the effectiveness and economic viability of implementing noble metal-based electrocatalysts. Functionalized metal–organic frameworks (MOFs) exhibit properties that can stabilize unstable nanoclusters in extremely small sizes by mitigating issues related to high surface energy and Ostwald's ripening effect. In this study, we present the synthesis of ultrasmall Ruthenium nanoclusters stabilized through a thiol-functionalized Ni-MOF (RuNC/Ni-M-SH). The stabilization of ruthenium under reduced conditions on the MOF surface is facilitated by the lower electronegativity and increased orbital overlapping effect of sulfur, resulting in an average size of 1.5 nm. X-ray photoelectron spectroscopy and X-ray absorption spectroscopy studies confirm a perturbed electronic structure, providing a fundamental understanding of electronic redistribution. With this favorable electronic structure, the catalytic OER activity of RuNC/Ni-M-SH surpasses that of the state-of-the-art RuO
2 , exhibiting a 3-fold increase in current density (242 mA cm–2 ) and a 82 mV reduced overpotential. Furthermore, in situ FTIR and Raman analyses were performed to analyze the catalytically active sites and intermediates. With 95% faradaic efficiency, the turnover frequency (TOF) and mass activity of RuNC/Ni-M-SH are several orders of magnitude higher than RuO2 . Remarkably, unlike other Ru-based catalysts, RuNC/Ni-M-SH demonstrates exceptional high stability, as evidenced by over 24 h of chronoamperometry study. These attributes of RuNC/Ni-M-SH established it as an economically sustainable OER electrocatalyst. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
25. Synthesis of non-cytotoxic Co3O4 nanocatalysts for thermocatalytic methane decomposition by resource recovery.
- Author
-
Mughal, Sheeza, Sehole, Hafiz Ali Haider, Mumtaz, Asad, Niazi, Muhammad Bilal Khan, Adnan, Fazal, Zhao, Hongbo, and Janjua, Hussnain A.
- Abstract
In sensing applications, the preferential adsorption of molecules on selective Co
3 O4 facets has been explored, yielding high sensitivity and selectivity. This tendency of the molecules can be exploited to enhance methane decomposition efficiency in transition metal catalysts other than nickel, which is known to cause acute toxicity. This study fabricated Co3 O4 catalysts with and without algal-resourced biogenic agents to calculate the preferential orientations or facets of the catalyst crystals. Henceforth, it evaluated their cytotoxicity and methane decomposition efficiency in a low-pressure chemical vapor deposition reactor from 750 to 850 °C using 0.04% (w/w) Co3 O4 /Al2 O3 -Si of nanocatalyst loaded on an Al2 O3 -coated p-type silicon support at different reaction conditions. Alg-Co3 O4 (311) nanocatalysts (0.158 eV/Å2 ), derived from algal biomass containing catalytically active stepped sites and catering efficient chemisorption of carbon atoms, executed 43.4% methane decomposition as opposed to 34% by NaBH4 -co-precipitated Ch-Co3 O4 (111) nanocatalysts (0.132 eV/Å2 ). The Alg-Co3 O4 (311) catalysts were nanometric in size; possessed higher ductility, per particle surface area; and were less cytotoxic for erythrocytes, leukocytes and U87 cells than the Ch-Co3 O4 (111) nanocatalysts. This state of the art provides a new platform to resource algal metabolites for tailoring catalytic efficiency at the nanoscale. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
26. N-acetyl-PABA@Cu(II) supported on Fe3O4 as the new heterogeneous catalytic system to assist the MCR derived synthesis of 2,2-dimethyl-2H-[1,3]dioxino[4,5-b]pyrrol-4(7H)-ones heterocyclic scaffolds
- Author
-
Yamini Patel, Ashok Kumar, and Pratibha Sharma
- Subjects
Ultrasonic irradiation ,Fused heterocycles ,Synthetic materials ,Nanocatalysis ,Magnetic nanoparticle ,Technology - Abstract
The present work elicits the synthesis of 2,2-dimethyl-2H-[1,3]dioxino[4,5-b]pyrrole-4(7H)-ones derivatives catalyzed by heterogeneous Fe3O4 magnetic nanoparticles supported N-acetyl-PABA@Cu(II), which address the limitations of traditional organic synthesis approaches in terms of sustainable and efficient, resulting in improved yields, higher selectivity with no waste. The decorum embraces four-component reactions (4CRs) of amines, aldehydes, meldrum’s acid, and nitromethane facilitated by Fe3O4-N-acetyl-PABA-Cu(II) in the presence of ethanol (CH3CH2OH) as an ecologically benign solvent under ultrasonic irradiation at room temperature. Outstanding conversion rates and selectivity were attained by the heterogeneous catalyst through great catalytic performance. The simple work-up, easy catalyst recovery, and no base or additional activators were required. Characterization of the structures of synthesized compounds and catalysts was corroborated through different spectroanalytical techniques viz; FTIR, 1H & 13C NMR, Mass elemental analyses, Energy-Dispersive X-ray Spectroscopy (EDX), Field-Emission Scanning Electron Microscope (FE-SEM), Powder X-ray Diffraction (XRD), Thermal Gravimetric Analysis (TGA), Differential Thermal Analysis (DTA), Particle size analysis and Zeta potential.
- Published
- 2024
- Full Text
- View/download PDF
27. Nanodiamond Supported Ultra-Small Palladium Nanoparticles as an Efficient Catalyst for Suzuki Cross-Coupling Reactions.
- Author
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Pocklanová, Radka, Warkad, Indrajeet R., Prucek, Robert, Balzerová, Anna, Panáček, Aleš, Kadam, Ravishankar G., Kvítek, Libor, and Gawande, Manoj B.
- Subjects
- *
SUZUKI reaction , *PALLADIUM , *NANODIAMONDS , *CHEMICAL stability , *CATALYTIC activity , *CATALYSTS - Abstract
A nanocatalyst comprising ultra-small palladium nanoparticles supported on nanodiamonds (ultra-small Pd/rNDs) was fabricated via a reduction of palladium (II) salt on oxidized nanodiamond. The prepared catalyst was characterized using XRD, XPS, ICP-MS, AAS, and TEM/HRTEM techniques, including STEM-EDS chemical mapping, which revealed that the modified material is a combination of reduced nanodiamond decorated with palladium nanoparticles. The as-prepared and well-characterized ultra-small Pd supported on rNDs displayed superb catalytic activity for Suzuki–Miyaura cross-coupling reactions at low temperature without any toxic solvents, to obtain the respective products in good-to-excellent yields (75–98%). The catalyst was easily separated from the reaction solution and was reused four times without loss of catalytic activity or chemical stability. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
28. Structural water molecules dominated p band intermediate states as a unified model for the origin on the photoluminescence emission of noble metal nanoclusters: from monolayer protected clusters to cage confined nanoclusters.
- Author
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Peng, Bo, Zhou, Jia-Feng, Ding, Meng, Shan, Bing-Qian, Chen, Tong, and Zhang, Kun
- Subjects
- *
PRECIOUS metals , *PHOTOLUMINESCENCE , *MOLECULES , *MONOMOLECULAR films - Abstract
In the past several decades, noble metal nanoclusters (NMNCs) have been developed as an emerging class of luminescent materials due to their superior photo-stability and biocompatibility, but their luminous quantum yield is relatively low and the physical origin of the bright photoluminescence (PL) of NMNCs remain elusive, which limited their practical application. As the well-defined structure and composition of NMNCs have been determined, in this mini-review, the effect of each component (metal core, ligand shell and interfacial water) on their PL properties and corresponded working mechanism were comprehensively introduced, and a model that structural water molecules dominated p band intermediate state was proposed to give a unified understanding on the PL mechanism of NMNCs and a further perspective to the future developments of NMNCs by revisiting the development of our studies on the PL mechanism of NMNCs in the past decade. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
29. Phosphine‐Enhanced Semi‐Hydrogenation of Phenylacetylene by Cobalt Phosphide Nano‐Urchins.
- Author
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Ropp, Anthony, André, Rémi F., and Carenco, Sophie
- Subjects
- *
ETHYNYL benzene , *ELECTRON donors , *PHOSPHIDES , *COBALT phosphide , *HETEROGENEOUS catalysts , *TRANSITION metals , *NANOPARTICLES , *PHOSPHINE - Abstract
Transition metal phosphides are promising, selective, and air‐stable nanocatalysts for hydrogenation reactions. However, they often require fairly high temperatures and H2 pressures to provide quantitative conversions. This work reports the positive effect of phosphine additives on the activity of cobalt phosphide nano‐urchins for the semi‐hydrogenation of phenylacetylene. While the nanocatalyst's activity was low under mild conditions (7 bar of H2, 100 °C), the addition of a catalytic amount of phosphine remarkably increased the conversion, e. g., from 13 % to 98 % in the case of PnBu3. The heterogeneous nature of the catalyst was confirmed by negative supernatant activity tests. The catalyst integrity was carefully verified by post‐mortem analyses (TEM, XPS, and liquid 31P NMR). A stereo‐electronic map was proposed to rationalize the activity enhancement provided over a selection of nine phosphines: the strongest effect was observed for low to moderately hindered phosphines, associated with strong electron donor abilities. A threshold in phosphine stoichiometry was revealed for the enhancement of activity to occur, which was related to the ratio of phosphine to surface cobalt atoms. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
30. Compressed carbon dioxide as a medium in catalytic hydrogenations: Engineering and chemistry
- Author
-
Garima Garg, Montserrat Gómez, Anna M. Masdeu-Bultó, and Yaocihuatl Medina González
- Subjects
Compressed carbon dioxide ,Carbon dioxide expanded liquids ,Homogeneous catalysis ,Nanocatalysis ,Solvent engineering ,Hydrogenation ,Technology - Abstract
In the frame of designing eco-friendly chemical processes, solvents represent a crucial economic and environmental concern. Compressed carbon dioxide (CO2) is an alternative green solvent for many industrial applications. Herein, we present the most relevant aspects of using compressed CO2 in metal-catalyzed hydrogenation reactions. In the first part, we discuss engineering fundamentals for the description of processes in supercritical fluids, gas-expanded liquids, continuous-flow applications and process design, including safety aspects and examples of heterogeneous catalysis. In the second part, we focus on catalytic systems based on both metal complexes and nano-systems, emphasizing how the catalysts have been adapted to the specificity of CO2. For this purpose, significant aspects such as the catalyst design, the reaction conditions and the use of co-solvents are considered. The main goal of this review is to show the advantages of using this green solvent in catalytic hydrogenations, including a critical analysis concerning its limitations.
- Published
- 2023
- Full Text
- View/download PDF
31. Recent Advances in Ligand Engineering for Gold Nanocluster Catalysis: Ligand Library, Ligand Effects and Strategies.
- Author
-
Wang, Mengyue, Chen, Yu, and Tang, Cen
- Subjects
- *
CATALYSIS , *GOLD , *ELECTRONIC control , *ENGINEERING , *LIGANDS (Chemistry) - Abstract
Advances in new ligands in the last decade facilitated in‐depth studies on the property‐relationship of gold nanoclusters and promoted the rational synthesis and related applications of such materials. Currently, more and more new ligands are being explored; thus, the ligand library of AuNCs is being expanded fast, which also enables investigation of ligand effects of AuNCs via direct comparison of different ligating shell with the identical gold core. It is now widely accepted that ligands influence the properties of AuNCs enormously including stability, catalysis, photoluminescence among others. These studies inspired ligand engineering of AuNCs. One of the goals for ligand engineering is to develop ligated AuNC catalysts in which the ligands are able to exert big‐enough influence on electronic and steric control over catalysis as in a transition‐metal or an enzyme system. Although increasing attention is paid to the further expansion of ligand library, the investigation of design principles and strategies regarding ligands are still in their infant stage. This review summarizes the ligands for AuNC synthesis, the ligand effects on stability and catalysis, and recently developed strategies in promoting AuNC catalytic performance via ligand manipulation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
32. Carbonylative Self‐Coupling of Aryl Boronic Acids Using a Confined Pd Catalyst within Melamine Dendron and Fibrous Nano‐Silica: A CO Surrogate Approach.
- Author
-
Kolekar, Yuvraj A., Saptal, Vitthal B., and Bhanage, Bhalchandra M.
- Subjects
- *
BORONIC acids , *HETEROGENEOUS catalysts , *CATALYSTS , *CATALYTIC activity , *MESOPOROUS silica , *HETEROGENEOUS catalysis , *MELAMINE - Abstract
Development of heterogeneous catalysts with tunable activity and selectivity has posed a persistent challenge. This study addresses this challenge by fabricating a hybrid environment through the combination of mesoporous silica and N‐rich melamine dendron via covalent grafting, allowing for controllable growth and encapsulation of Pd NPs. This catalyst presented an excellent catalytic activity for the oxidative carbonylative self‐coupling of aryl boronic acids to afford symmetric biaryl ketones using N‐formyl saccharin as a sustainable solid CO source and Cu as a co‐catalyst. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
33. Microwave-Assisted Synthesis of Pd Nanoparticles into Wood Block (Pd@wood) as Efficient Catalyst for 4-Nitrophenol and Cr(VI) Reduction.
- Author
-
Zhang, Zhao, Besserer, Arnaud, Rose, Christophe, Brosse, Nicolas, Terrasson, Vincent, and Guénin, Erwann
- Subjects
- *
WOOD , *NANOPARTICLE synthesis , *SEWAGE , *WASTEWATER treatment , *INDUSTRIAL wastes , *MICROWAVE heating - Abstract
Palladium (Pd) nanoparticle catalysis has attracted increasing attention due to its efficient catalytic activity and its wide application in environmental protection and chemical synthesis. In this work, Pd nanoparticles (about 71 nm) were synthesized in aqueous solution by microwave-assisted thermal synthesis and immobilized in beech wood blocks as Pd@wood catalysts. The wood blocks were first hydrothermally treated with 10% NaOH solution to improve the internal structure and increase their porosity, thereby providing favorable attachment sites for the formed Pd nanoparticles. The stable deposition of Pd nanoparticle clusters on the internal channels of the wood blocks can be clearly observed. In addition, the catalytic performance of the prepared Pd@wood was investigated through two model reactions: the reduction of 4-nitrophenol and Cr(VI). The Pd@wood catalyst showed 95.4 g−1 s−1 M−1 of normalized rate constant knorm and 2.03 min−1 of the TOF, respectively. Furthermore, Pd nanoparticles are integrated into the internal structure of wood blocks by microwave-assisted thermal synthesis, which is an effective method for wood functionalization. It benefits metal nanoparticle catalysis in the synthesis of fine chemicals as well as in industrial wastewater treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
34. Chiral Carbon Nanodots Can Act as Molecular Catalysts in Chemical and Photochemical Reactions.
- Author
-
Bartolomei, Beatrice, Corti, Vasco, and Prato, Maurizio
- Subjects
- *
CARBON nanodots , *CHEMICAL reactions , *CHEMICAL amplification , *CATALYSTS , *CIRCULAR dichroism , *AMINO group , *ORGANOCATALYSIS , *PHOTOCHEMISTRY - Abstract
In this work, a microwave synthesis followed by a simple purification process produces a new type of chiral Carbon Nanodots (CNDs). These CNDs are soluble in organic solvents, exhibit amino groups on their surface and display interesting absorption and emission properties along with mirror image profiles in the electronic circular dichroism spectrum. All these features set the stage for CNDs to act as multifunctional catalytic platforms, able to promote diverse chemical transformations. In particular, the outer shell composition of CNDs was instrumental to carry out organocatalytic reactions in an enantioselective fashion. In addition, the redox and light‐absorbing properties of the material are suitable to drive photochemical processes. Finally, the photoredox and organocatalytic activations of CNDs were exploited at the same time to promote a cross‐dehydrogenative coupling. This work demonstrates that CNDs can be used as catalysts to promote multiple reactivities, previously considered exclusive domain of molecular catalysts. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
35. Pd‐Enriched‐Core/Pt‐Enriched‐Shell High‐Entropy Alloy with Face‐Centred Cubic Structure for C1 and C2 Alcohol Oxidation.
- Author
-
Lao, Xianzhuo, Liao, Xuejiang, Chen, Chen, Wang, Jiasheng, Yang, Likang, Li, Ze, Ma, Jun‐Wei, Fu, Aiping, Gao, Hongtao, and Guo, Peizhi
- Subjects
- *
ALCOHOL oxidation , *OXIDATION of methanol , *ALLOYS , *ATMOSPHERIC pressure - Abstract
High‐entropy alloy nanoparticles (HEA NPs) have aroused great interest globally with their unique electrochemical, catalytic, and mechanical properties, as well as diverse activity and multielement tunability for multi‐step reactions. Herein, a facile low‐temperature synthesis method at atmospheric pressure is employed to synthesize Pd‐enriched‐HEA‐core and Pt‐enriched‐HEA‐shell NPs with a single phase of face‐centred cubic structure. Interestingly, the lattice of both Pd‐enriched‐HEA‐core and Pt‐enriched‐HEA‐shell enlarge during the formation process of HEA, with tensile strains included in the core and shell of HEA. The as‐obtained PdAgSn/PtBi HEA NPs show excellent electrocatalytic activity and durability for methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR). The specific (mass) activity of PdAgSn/PtBi HEA NPs for MOR is 4.7 mA cm−2 (2874 mA mg(Pd+Pt)−1), about 1.7 (5.9) and 1.5 (4.8) times higher than that of commercial Pd/C and Pt/C catalysts, respectively. Additional to high‐entropy effect, Pt sites and Pd sites on the interface of the HEA act synergistically to facilitate the multi‐step process towards EOR. This study offers a promising way to find a feasible route for scalable HEA manufacturing with promising applications. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
36. Enhanced hydrogen generation via overall water splitting using novel MoS2-BN nanoflowers assembled TiO2 ternary heterostructures.
- Author
-
Ali, Syed Asim and Ahmad, Tokeer
- Subjects
- *
INTERSTITIAL hydrogen generation , *HETEROSTRUCTURES , *WATER use , *TITANIUM dioxide , *ELECTROCHEMICAL analysis , *CHARGE transfer - Abstract
Envisaging headway in the applicability of sustainable H 2 energy, the novel report of the fabrication of MoS 2 -BN/TiO 2 (MBT) heterogeneous nanostructures has been proposed via facile in-situ hydrothermal route with an aim to propound the superior substitute of noble metal based conventionally employed catalytic system to surmount their exorbitant cost. We inferred the ascendancy of MoS 2 -BN nanoflowers over pristine MoS 2 counterpart in an establishment of TiO 2 based heterostructured catalysis. MBT heterostrucutres were extensively scrutinized with respect to their structural, optoelectronic and computational characteristics. En route to enhanced H 2 evolution, we have investigated the significance of interfacial junctions and exposed sites in the MBT heterostructures. In order to achieve broader pertinence in green H 2 fuel, the performance of MBT heterostrucutres was ascertained with subject to photochemical, electrochemical and photo-electrochemical (PEC) water splitting. Loaded concentration of MoS 2 -BN was varied in MBT catalysts and 2.5 wt% MoS 2 -BN/TiO 2 exhibited optimum photocatalytic response with an H 2 production rate of 2.6 mmol/g/h with 6.94% AQY and improved photo-current response of 0.99 mA/cm2 towards PEC. Electrochemical investigations further intensified the caliber of MBT as HER catalyst ascribed to the higher cathodic current density of 49.23 mA/cm2 at 1.22 V potential. The advancement in the catalytic efficiency of MBT heterostructures was evidenced by the synergetic relationship between MoS 2 -BN and TiO 2 which stimulated the separation and transfer of photo-charged carriers, and lowered the overpotential values consequently surging the kinetics of H 2 evolution. [Display omitted] • Novel MoS 2 -BN/TiO 2 heterostructures via two-step environmentally benign hydrothermal route. • Role of MoS 2 -BN nanoflowers in enhancing the catalytic efficiency of TiO 2. • Effective band-alignment between MoS 2 -BN and TiO 2 propelled the rate of interfacial charge transfer. • Photo/electro/photo-electrochemical routes of H 2 evolution via overall water splitting. • Comparative analysis between electrochemical and photo-electrochemical operations to optimize response towards H 2 production. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
37. Nanocarbons in quantum regime: An emerging sustainable catalytic platform for organic synthesis.
- Author
-
Dandia, Anshu, Saini, Pratibha, Sethi, Mukul, Kumar, Krishan, Saini, Surendra, Meena, Savita, Meena, Swati, and Parewa, Vijay
- Subjects
- *
ORGANIC synthesis , *CONDENSATION reactions , *RING-opening reactions , *QUANTUM dots , *CHEMICAL bonds , *CATALYST synthesis - Abstract
Fluorescent carbon quantum dots (CQDs), specified by feature sizes of <10 nm, have become a mystic newcomers in the world of nanoscience and attracted much focus of synthetic chemists since the last decade due to their esoteric physico-chemical features. Because of these magical characteristics, carbon dots-based catalytic systems have unlocked the gateway for eco-friendly, benign, and cost-effective next-generation platform for "Nanocatalysis and Photocatalysis" in organic synthesis. The introduction of CQDs in organic synthesis allows the designing new reactions or catalysis in which unique/unprecedented connection/disconnection of chemical bonds has been implemented for the construction of new molecular architectures. This critical review presents a comprehensive study of the catalytic and photocatalytic efficiency of CQDs in organic synthesis which has initiated a more sustainable strategy in to the catalysis field. By systematic summarization and categorization of various organic transformations such as coupling reactions, oxidation reactions, reduction reactions, condensation reactions, ring-opening reactions, epoxidation, C-H activation, etc., a clear picture of all available catalytic and photocatalytic strategies for CQDs are presented and their unique role in various catalytic approaches for specific reactions are discussed in detail. Catalytic aspects of CQDs in heterocyclic synthesis are also been reviewed. Finally, challenges and future aspects associated with the green catalytic efficiency of CQDs in organic synthesis are highlighted. Herein, this review summarizes the current investigations on CQDs for various organic transformations during last 10 years. We experience that the entire potential of CQDs in organic synthesis has yet to be fully explored in organic synthesis. We hope that this review is serving as a humble urge to encourage other organic chemists for further use of CQDs as a sustainable catalyst in organic synthesis. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. Influence of the Cobalt Active Site Neighbours in NiCo Nanocatalysts for Phosphine‐Assisted Silane Activation.
- Author
-
Ropp, Anthony and Carenco, Sophie
- Subjects
- *
NANOPARTICLES , *PRECIOUS metals , *COBALT , *CATALYTIC activity , *NEIGHBORS , *SILANE - Abstract
NiCo nanoparticles are active catalysts for a number of reactions, as an interesting alternative to noble metals. In particular, phosphine‐covered NiCo nanoparticles with a 1 : 1 metal ratio were found to be active at room temperature for Si−H bond activation. However, it was unclear which of the two metals was the active site and if the neighbouring atoms influenced the reaction efficiency. We designed nanoparticles with a nickel core and a limited amount of cobalt surface sites, just below or just above a monolayer amount, to investigate this question. We showed that the trend in catalytic activity is consistent with cobalt being the active site, and it shows a higher activity when its immediate neighbours are cobalt atoms. This was consistently observed with two phosphine ligands, PPh3 and PnBu3, while the first allowed a higher conversion rate than the second. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
39. Dynamic Activation of Ga Sites by Pt Dopant in Low‐Temperature Liquid‐Metal Catalysts.
- Author
-
Lambie, Stephanie, Steenbergen, Krista G., and Gaston, Nicola
- Subjects
- *
DOPING agents (Chemistry) , *CATALYSTS , *OXIDATION of methanol , *CATALYST supports , *MOLECULAR dynamics , *ADSORBATES , *METAL catalysts , *GALLIUM alloys - Abstract
Liquid GaPt catalysts with Pt concentrations as low as 1×10−4 atomic % have recently been identified as highly active for the oxidation of methanol and pyrogallol under mild reaction conditions. However, almost nothing is known about how liquid state catalysts support these significant improvements in activity. Here, ab initio molecular dynamics simulations are employed to examine GaPt catalysts in isolation and interacting with adsorbates. We find that persistent geometric features can exist in the liquid state, given the correct environment. We postulate that the Pt dopant may not be limited to direct involvement in catalysis of reactions, but rather that its presence can also enable Ga atoms to become catalytically active. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
40. Synthesis of Bioactive Thioxoimidazolidinones, Oxazolidinones, Thioxothiazolidinones, Thiazolidinediones
- Author
-
Doustkhah, Esmail, Arlan, Fatemeh Majidi, Ameta, Keshav Lalit, editor, Kant, Ravi, editor, Penoni, Andrea, editor, Maspero, Angelo, editor, and Scapinello, Luca, editor
- Published
- 2022
- Full Text
- View/download PDF
41. Emerging Contaminants Removal from Wastewater by Nanotechnological Methods
- Author
-
Desireddy, Swathi, Sabumon, P. C., Agarwal, Avinash Kumar, Series Editor, P. Singh, Swatantra, editor, Gupta, Tarun, editor, and Maliyekkal, Shihabudheen M., editor
- Published
- 2022
- Full Text
- View/download PDF
42. Unraveling the chemoselective catalytic, photocatalytic and electrocatalytic applications of copper supported WO3 nanosheets
- Author
-
Farha Naaz, Saad M. Alshehri, Yuanbing Mao, and Tokeer Ahmad
- Subjects
Nanocatalysis ,Olefins epoxidation ,Epoxide synthesis ,Photocatalysis ,Electrocatalytic HER ,Hydrogen generation ,Chemistry ,QD1-999 - Abstract
Copper (1–5%)-doped tungsten oxide nanosheets has been synthesized using a solvothermal route for catalytic epoxidation of olefins to epoxides and hydrogen production. 5% Cu-WO3 (CW5) nanosheets is found to be highly efficient in selectively catalyzing olefins substrates (Styrene and Cyclohexene) to their corresponding epoxides with total conversion and better selectivity. CW5 nanosheets also exhibited highest photocatalytic activity with rate of hydrogen evolution of 2.69 mmol g−1 cat h−1 under visible light. It can also unveil outstanding performance as bi-functional water splitting electrocatalyst with 58 mA/cm2 current density at −1.2 V for HER and 1.58 mA/cm2 at an onset potential of 0.8 V for OER in alkaline medium.
- Published
- 2023
- Full Text
- View/download PDF
43. Superparamagnetic energetic nanoparticles: a surface self-propagation pathway for the thermal decomposition of ammonium perchlorate.
- Author
-
Gaete, José, Valdebenito, Cristián, Dibdalli, Yuvaraja, Arroyo, Juan Luis, Norambuena, Ángel, Valenzuela, Fernando, Basualto, Carlos, Abarca, Gabriel, and Morales-Verdejo, César
- Subjects
- *
MAGNETITE , *SUPERPARAMAGNETIC materials , *AMMONIUM perchlorate , *MAGNETIC materials , *NANOPARTICLES , *NITRILOTRIACETIC acid , *RAW materials , *SUPERCONDUCTING magnets - Abstract
In this work, our research group developed usable low-cost superparamagnetic nanoparticles (Fe3O4@NTA) that behave as an excellent energetic material to accelerate the thermal decomposition of ammonium perchlorate (AP). As a synthetic strategy, magnetite nanoparticles (Fe3O4) were coated with nitrilotriacetic acid (NTA) by a simple preparation method. Based on High-resolution transmission electron microscopy (HR-TEM) and vibrating sample magnetometer (VSM) results, Fe3O4@NTA presents a mean diameter of 7.4 nm and superparamagnetic behavior. Chemical characterization by Energy-dispersive X-ray spectroscopy (XPS), Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) provided enough evidence for the presence of a carboxylic acid group and magnetite in the sample. The Fe3O4@NTA catalyst diminishes AP high-temperature decomposition (HTD) to 342 °C and shows a low activation energy (98.02 kJ mol−1). In addition, after the burning rate test, it was observed that these resulting nanoparticles showed an adequate magnetic response against an external magnet. These results are promising for future research, as the opportunity opens to reuse this functional magnetic material in successive catalytic cycles, thus contributing soon to the recycling of raw materials necessary for interplanetary travel. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
44. Catalytic Degradation of Azo Dyes by Silver Nanoparticles †.
- Author
-
Marques, Nayally Rayany S., Lima, Max Taylo A., Pereira, Giovannia A. L., and Pereira, Goreti
- Subjects
AZO dyes ,SILVER nanoparticles ,CATALYSIS ,CHEMICAL affinity ,CONGO red (Staining dye) - Abstract
The high industrial demand generates an increased consumption and a high waste of materials that impacts the environment in different spheres. One of the most affected environments are aquatic systems. Moreover, one of the most common forms of water contamination is the improper disposal of dyes by industries such as textiles, cosmetics, and pharmaceuticals. These dyes are organic substances that can give color to a substrate through chemical affinity. The most commonly used synthetic dyes are the ones containing the azo group, which have been reported as carcinogenic, mutagenic, and genotoxic, causing harm to the environment and living beings. Therefore, the study of methods that contribute to the degradation of these species will contribute to better treatment of polluted aquatic environments. Thus, the main objective of this work was to promote the catalytic degradation of organic dyes, such as Methyl Orange and Congo Red, through silver nanoparticles (AgNPs). For this, AgNPs were synthesized with spherical shapes using two stabilizers (polyvinylalcohol-PVA, and polyvinylpyrrolidone-PVP). Subsequently, the AgNPs were applied for the degradation of organic dyes, with the catalysis analyzed via UV-Vis absorption spectrometry in a maximum time of 40 min. Finally, it was observed that these nanocatalysts were successful in degrading the organic dyes. Thus, AgNPs have the potential to be used as catalysts for wastewater treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
45. Study of the Stabilizing Agent Influence in the Catalytic Degradation of Methylene Blue Using Silver Nanoparticles †.
- Author
-
Lima, Max T. A., Figueiredo, Danilo M. M., Marques, Nayally R. S., Pereira, Giovannia A. L., and Pereira, Goreti
- Subjects
STABILIZING agents ,CATALYSIS ,METHYLENE blue ,SILVER nanoparticles ,INDUSTRIAL waste management - Abstract
Inadequate treatment of industrial waste causes the contamination of rivers and seas, impacting human health and aquatic biodiversity. Among the pollutants are industrial dyes, such as methylene blue (MB), which is toxic in high doses and prevents solar radiation from penetrating the water's surface. To reduce water pollution, the organic dyes could be degraded, generating less harmful and colorless substances. The use of nanoparticles as catalysts has been gaining attention since they have excellent catalytic activity due to their high surface-to-volume ratio. Thus, this work aims to study the use of silver nanoparticles (AgNPs) to degrade MB. AgNPs were prepared in water using the chemical reduction strategy and four different organic stabilizers: sodium citrate, ascorbic acid, polyvinylpyrrolidone, and poly(vinyl alcohol). The MB degradation in the presence of the AgNPs was monitored by UV-Vis absorption spectroscopy. The results showed the formation of AgNPs with a spherical shape for all the stabilizers used. All the AgNPs prepared were efficient in the degradation of MB, having degraded more than 90%. However, the AgNPs stabilized with sodium citrate and polyvinylpyrrolidone presented the best catalytic performance. Nevertheless, the four AgNPs prepared are potential catalysts for the degradation of organic dyes of wastewater. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
46. Exploiting multiferroicity of TbFeO3 nanoparticles for hydrogen generation through photo/electro/photoelectro-catalytic water splitting.
- Author
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Khan, Huma, Lone, Irfan Hussain, Lofland, Samuel Edward, Ramanujachary, Kandalam Venkata, and Ahmad, Tokeer
- Subjects
- *
INTERSTITIAL hydrogen generation , *CHARGE transfer kinetics , *MULTIFERROIC materials , *X-ray powder diffraction , *NANOPARTICLES ,CATALYSTS recycling - Abstract
Hydrogen is a potential future energy source that could replace conventional fuel and provide the necessary energy. Multiferroic materials are the most likely choices for water splitting due to their ferroelectric characteristics and ability to function as magnetically recoverable catalysts. Multiferroic terbium orthoferrite nanoparticles were synthesized at low temperature by the polymeric citrate precursor route to study the photocatalytic, electrocatalytic and photoelectrochemical activity towards hydrogen production. Powder X-ray diffraction revealed successful formation of orthorhombic TbFeO 3 nanoparticles. A larger aspect ratio of 3.9 and a bandgap of 2.13 eV were seen in the elongated TbFeO 3 nanoparticles, which contributes to the photo/electro-catalytic activity. Magnetic and ferroelectric studies revealed weak ferromagnetism and ferroelectric polarization of 0.037 μC cm−2 in TbFeO 3 nanoparticles, confirming multiferroicity. Visibly active and multiferroic TbFeO 3 nanoparticles showed notable hydrogen evolution of 1.44 mmol h−1 g−1. In electrocatalytic and photoelectrochemical water splitting investigations, TbFeO 3 nanoparticles demonstrated current densities of 30 and 60 mA cm−2, respectively. EIS, TRPL, transient photocurrent and Mott-schottky measurements were used to examine charge transfer kinetics. The high H 2 evolution and good OER/HER tests were attributed to increased charger separation efficiency due to ferroelectricity induced band bending. [Display omitted] • Multiferroic orthorhombic TbFeO 3 NPs stabilized by low temperature precursor route. • Morphological studies show elongated nanoparticles with aspect ratio of 3.9. • Significant photocatalytic H 2 evolution rate of 1.44 mmol h−1 g−1. • High OER/HER/photocurrent density in TbFeO 3 NPs is reported. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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47. Bismuth-Based Multi-Component Heterostructured Nanocatalysts for Hydrogen Generation.
- Author
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Shaheen, Saman, Sadiq, Iqra, Ali, Syed Asim, and Ahmad, Tokeer
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- *
NANOPARTICLES , *INTERSTITIAL hydrogen generation , *BISMUTH , *CHARGE transfer , *AUTOMOBILE industry , *HETEROSTRUCTURES , *HETEROJUNCTIONS - Abstract
Developing a unique catalytic system with enhanced activity is the topmost priority in the science of H2 energy to reduce costs in large-scale applications, such as automobiles and domestic sectors. Researchers are striving to design an effective catalytic system capable of significantly accelerating H2 production efficiency through green pathways, such as photochemical, electrochemical, and photoelectrochemical routes. Bi-based nanocatalysts are relatively cost-effective and environmentally benign materials which possess advanced optoelectronic properties. However, these nanocatalysts suffer back recombination reactions during photochemical and photoelectrochemical operations which impede their catalytic efficiency. However, heterojunction formation allows the separation of electron–hole pairs to avoid recombination via interfacial charge transfer. Thus, synergetic effects between the Bi-based heterostructured nanocatalysts largely improves the course of H2 generation. Here, we propose the systematic review of Bi-based heterostructured nanocatalysts, highlighting an in-depth discussion of various exceptional heterostructures, such as TiO2/BiWO6, BiWO6/Bi2S3, Bi2WO6/BiVO4, Bi2O3/Bi2WO6, ZnIn2S4/BiVO4, Bi2O3/Bi2MoO6, etc. The reviewed heterostructures exhibit excellent H2 evolution efficiency, ascribed to their higher stability, more exposed active sites, controlled morphology, and remarkable band-gap tunability. We adopted a slightly different approach for reviewing Bi-based heterostructures, compiling them according to their applicability in H2 energy and discussing challenges, prospects, and guidance to develop better and more efficient nanocatalytic systems. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
48. Nanocatalysis of silver-nanobioprobe based supersensitive electrochemical detection of Salmonella serotypes targeting virulence protein.
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Bisht, Bhawana, Bhardwaj, Priya, Chauhan, Sakshi, Sagrika, Vedika, Basnal, Namita, and Bhalla, Vijayender
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- *
MEMBRANE proteins , *SALMONELLA detection , *PEPTIDES , *TRANSMISSION electron microscopy , *DRINKING water - Abstract
Herein, we report a supersensitive and specific detection of Salmonella employing nanocatalysis of silver nanoparticle (AgNp). A nanobioprobe was developed employing specific antibody (Ab) that binds to a peptide present in transmembrane protein of Salmonella. We have studied 7 surface-exposed peptide hits from conserved virulence proteins (PagC, ST50, PagN, CdtB and FliC). These peptides were experimentally evaluated by BLI (Bio layer interferometry) for their reactivity towards antisera raised against an admix of major Salmonella serogroups. The most promising peptide was used to generate Ab with binding affinity Kd of 5.6 × 10−9 M. The Ab exhibited high specificity towards entire Salmonella serotypes prevalent in foods, as illustrated by FACS (Fluorescence-activated cell sorting) study. The Ab-AgNp probe was blocked with a dual layer to prevent non-specific interactions, confirmed by employing BLI and TEM (Transmission electron microscopy). For the electrochemical detection, the autonanocatalysis of AgNp in presence of H 2 O 2 was used to generate numerous Ag+ resulting in an amplified signal that could detect 10 cells/mL. The relative standard deviation (RSD) was observed to be 4.5%. The platform achieved recovery of 100–112% calculated for 102 cells/mL. The performance was validated in milk, buffer peptone water (BPW) and tap water by spiking studies. The study highlights the effectiveness of efficiently blocked AgNp-mediated probes for the highly selective and sensitive detection of Salmonella , representing a significant advancement in bacterial sensing. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
49. Nanoengineering of Catalysts for Enhanced Hydrogen Production
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Jhonatan Luiz Fiorio, Maitê Lippel Gothe, Emerson Cristofer Kohlrausch, Maria Luísa Zardo, Auro Atsushi Tanaka, Roberto Batista de Lima, Anderson Gabriel Marques da Silva, Marco Aurélio Suller Garcia, Pedro Vidinha, and Giovanna Machado
- Subjects
hydrogen ,nanomaterials ,controlled synthesis ,nanoengineering ,nanocatalysis ,hydrogen production technologies ,Science (General) ,Q1-390 - Abstract
Hydrogen (H2) has emerged as a sustainable energy carrier capable of replacing/complementing the global carbon-based energy matrix. Although studies in this area have often focused on the fundamental understanding of catalytic processes and the demonstration of their activities towards different strategies, much effort is still needed to develop high-performance technologies and advanced materials to accomplish widespread utilization. The main goal of this review is to discuss the recent contributions in the H2 production field by employing nanomaterials with well-defined and controllable physicochemical features. Nanoengineering approaches at the sub-nano or atomic scale are especially interesting, as they allow us to unravel how activity varies as a function of these parameters (shape, size, composition, structure, electronic, and support interaction) and obtain insights into structure–performance relationships in the field of H2 production, allowing not only the optimization of performances but also enabling the rational design of nanocatalysts with desired activities and selectivity for H2 production. Herein, we start with a brief description of preparing such materials, emphasizing the importance of accomplishing the physicochemical control of nanostructures. The review finally culminates in the leading technologies for H2 production, identifying the promising applications of controlled nanomaterials.
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- 2022
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50. Base-free aqueous Suzuki–Miyaura coupling reaction using recoverable bi-functional Pd supported nanocatalyst.
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Rajabi, Fatemeh, Burange, Anand S., and Luque, Rafael
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- *
SUSTAINABLE chemistry , *BASE catalysts , *COUPLING reactions (Chemistry) , *SUZUKI reaction , *CATALYTIC activity , *PALLADIUM catalysts - Abstract
[Display omitted] • Pyridine-palladium polyorganosiloxane catalyst was synthesized. • Hybrid nanomaterial with high catalytic activity in Suzuki couplings. • Reaction amenable to a range of aryl chlorides under base-free and aerobic conditions. • Material exhibiting exceptional stability (reused up to six times) A solid base catalyst comprising pyridine-palladium polyorganosiloxane framework was synthesized via a grafting method. The resulting organic–inorganic hybrid palladium nanomaterial was characterized by 13C CP-MAS NMR, 29Si CP-MAS NMR, XRD, EDX, TEM, TGA, and the BET measurements. The hybrid palladium nanomaterial exhibited high catalytic activity for the Suzuki–Miyaura cross-coupling reaction between aryl chlorides and phenylboronic acid under base-free and aerobic conditions. A maximum turnover number (TON) of 3150, with a 0.2 mol% Pd loading and a reaction temperature of 80 °C in aqueous solution. The catalyst demonstrated remarkable stability, maintaining its activity even after six cycles of reuse without significant loss of activity. TEM images showed that the catalyst retained its structure and high-order mesostructure after several uses. ICP-AES also confirmed the absence of palladium contamination in the final products. Leaching test studies further confirmed the true heterogeneous nature of the developed catalytic system. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
Catalog
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