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green synthesis of Silver Nanoparticles Using Aqueous Orange and Lemon Peel Extract and Evaluation of Their Antimicrobial Properties

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Advances in Nanoparticles 2024年第2期13卷 11-28页

作者： Amra Bratovcic Amna Dautovic Department of Physical Chemistry and Electrochemistry Faculty of Technology University of Tuzla Tuzla Bosnia and Herzegovina Multilab Tuzla Bosnia and Herzegovina

green synthesis of silver nanoparticles (AgNPs) using aqueous extracts of orange and lemon peels, as a reducing agent, and silver nitrate salts as a source of silver ions is a promising field of research due to the versatility of biomedical applications of metal nanoparticles. In this paper, AgNPs were synthetized at different reaction parameters such as the type and concentration of the extracts, metal salt concentration, temperature, speed stirring, and pH. The antibacterial properties of the obtained silver nanoparticles against E. coli, as well as the physical and chemical characteristics of the synthesized silver nanoparticles, were investigated. UV-Vis spectroscopy was used to confirm the formation of AgNPs. In addition to green biogenic synthesis, chemical synthesis of silver nanoparticles was also carried out. The optimal temperature for extraction was 65˚C, while for the synthesis of AgNPs was 35˚C. The synthesis is carried out in an acidic environment (pH = 4.7 orange and pH = 3.8 lemon), neutral (pH = 7) and alkaline (pH = 10), then for different concentrations of silver nitrate solution (0.5 mM - 1 mM), optimal time duration of the reaction was 60 min and optimal stirring speed rotation was 250 rpm on the magnetic stirrer. The physical properties of the synthesized silver nanoparticles (conductivity, density and refractive index) were also studied, and the passage of laser light through the obtained solution and distilled water was compared. Positive inhibitory effect on the growth of new Escherichia coli colonies have shown AgNPs synthesized at a basic pH value and at a 0.1 mM AgNO3 using orange or lemon peel extract, while for a 0.5 mM AgNO3 using lemon peel extract.

关键词： green synthesis Silver Nanoparticles Orange and Lemon Peel Extract Antibacterial Activity Escherichia coli

One-Pot green synthesis of 1, 4-Dihydropyridine Derivatives Using Polyindole TiO2 Nanocatalyst by Solvent Free Method

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Open Journal of Composite Materials 2024年第3期14卷 109-123页

作者： Deepak Babasaheb Phasage Sanjay K. Sharma Balram Tripathi Sonia Chahar Srivastava Department of Chemistry JECRC University Jaipur India S. S. Jain Subodh PG College Jaipur India

This study used a Polyindole in combination with TiO2 nanocatalyst as an efficient heterogeneous catalyst to carry out a multi-component Hantzsch reaction involving different aromatic aldehydes with methyl acetoacetate, and aqueous ammonium to create 1,4-dihydropyridine derivatives under solvent free condition at ambient temperature. A broad range of aldehydes and methyl acetoacetates, ranging from heteroaromatic to polyaromatic one, with high level of functional group tolerance can be used to provide the desired products possessing relevant medicinal moiety in high yields. This technology has prospective advantages over current protocols, including the utilization of a cheap, stable, recyclable, and safe catalyst, quicker reaction times with higher yields and simple product isolation.

关键词： TiO2 Nanocatalyst green synthesis Surface Morphology

Rapid green synthesis of Silver Nanoparticles by Reishi and Their Antibacterial Activity and Mechanisms

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Journal of Biomaterials and Nanobiotechnology 2024年第3期15卷 51-63页

作者： Akamu J. Ewunkem T’nasia Priester Desia Williams Bailey Ariyon Ilunga Tshimanga Brittany Justice Dinesh K. Singh Department of Biological Sciences Winston-Salem State University Winston-Salem North Carolina USA

Nanotechnology is a rapidly growing field in biomedical engineering with references to efficiency, safety, and cost-effective approaches. Herein, the objective of this study was to examine an innovative approach to rapidly synthesis silver nanoparticles from an aqueous extract of medicinal mushroom Ganoderma lucidum (also known as reishi). The structural and dimensional dispersion of the biosynthesized silver nanoparticles from reishi was confirmed by UV-Vis spectrophotometer (UV-Vis) and Scanning Electron Microscopy (SEM) analysis. Additionally, the biosynthesized silver nanoparticles from resihi were used to explore their potential antimicrobial activity against Staphylococcus aureus and Micrococcus luteus and Escherichia coli and Klebsiella pneumoniae. The results from this study revealed that the silver nanoparticles mediated by reishi adopted a spherical shape morphology with sizes, less than 100 nm and revealed strong absorption plasmon band at 440 nm. Furthermore, the biosynthesized silver nanoparticles from reishi exhibited antibacterial activity against the tested S. aureus and M. luteus and E. coli and K. pneumoniae by altering their morphology which signifies their biomedical potential.

关键词： Nanotechnology Reishi Nanoparticles Antimicrobial green synthesis

green synthesis of novel conjugated poly(perylene diimide)as cathode with stable sodium storage

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Nano Research 2023年第7期16卷 9538-9545页

作者： Jinyun Zheng Xinxin Liu Wenbin Li Wenjie Li Xiangming Feng Weihua Chen College of Chemistry&green Catalysis Center Zhengzhou UniversityZhengzhou 450001China

Conjugated polymers of organic carbonyl compounds are promising electrode materials for energy storage devices owing to the renewable development prospects,structural variability,and better insolubility in ***,the synthesis methods in solution are cumbersome and complicated in separation and purification,and require the introduction of functional groups and use of expensive *** this work,a novel conjugated poly(3,4,9,10-perylenetetracarboxylic diimide)(PPI)with superior thermal stability and lower solubility was prepared successfully by a green facile mechanical ball milling *** PPI exhibits enhanced electrochemical dynamics performance,preferable rate capability,higher discharge capacity,and excellent cycling stability of 450 cycles at 0.2 C with higher capacity retention of 85.7%when used as cathode material for sodium-ion ***,the in-situ X-ray diffraction(XRD)and in-situ Raman investigations combined with the Fourier transform infrared(FT-IR)and X-ray photoelectron spectroscopy(XPS)were carried out to investigate the sodium storage *** results indicate that only two sodium ions are bound to two opposite carbonyl groups of PPI monomer to form sodium enolates during normal charging and discharging and to deliver available reversible capacity.

关键词： sodium-ion battery organic cathode carbonyl compound stability green synthesis

green synthesis of MnO_x nanostructures and studies of their supercapacitor performance

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Science China Chemistry 2015年第4期58卷 627-633页

作者： Wei Du Xiaoqian Xu Di Zhang Qingyi Lu Feng Gao State Key Laboratory of Coordination Chemistry Nanjing National Laboratory of Microstructures Coordination Chemistry Institute School of Chemistry and Chemical Engineering Nanjing University Department of Materials Science and Engineering Nanjing University

Manganese oxides with different crystalline phases and morphologies were prepared by calcining Mn CO3 precursors. The Mn CO3 precursors with different morphologies were obtained through a green route under hydrothermal conditions with orange pericarp extracting solution as the reducing agent. By calcining the precursor under different temperatures and atmospheres, Mn Ox with different stoichiometric ratios(i.e., Mn O, Mn O2, Mn2O3, and Mn3O4) can be obtained. Electrochemical studies reveal that among these manganese oxides, Mn O or Mn O2 are more suitable as supercapacitor working electrodes than Mn2O3 or Mn3O4. They exhibit high specific capacitance up to 296.6 F/g and also possess good cycling stability, which make them potential electrode materials for supercapacitors.

关键词： MnOx nanostructures green synthesis supercapacitor

green synthesis of Nitrogen-to-Ammonia Fixation: Past, Present, and Future

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Energy & Environmental Materials 2022年第2期5卷 452-457页

作者： Jianyun Zheng Li Jiang Yanhong Lyu San Ping Jiang Shuangyin Wang State Key Laboratory of Chem/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Department of Educational Science Hunan First Normal UniversityChangsha 410205China Curtin University Perth WAAustralia

The nitrogen(N2)-to-ammonia(NH3)fixation driven by renewable energy has an attractive prospect to relieve the global warming and reduce the consumption of fossil ***,photocatalytic,electrochemical,and photoelectrochemical approaches are developed as the next-generation NH3 synthesis technologies to substitute the Haber–Bosch ***,the NH3 yield rate of nitrogen reduction reaction(NRR)by green approaches is extremely low,resulting in the current dilemma of NRR and contamination ***,in this mini review,the past advances on the sustainable NRR are briefly summarized in the three aspects as follows:the selectivity and adjustment of various catalysts,the type of electrolyte/solvent system,and the investigation of reaction ***,the recent critical activities in the area of sustainable NH3 synthesis are analyzed and discussed deeply,and a perspective for rational and healthy development of this area is provided positively。

关键词： current dilemma enhanced performances future challenges green synthesis nitrogen-to-ammonia fixation

green synthesis of fluorescent carbon quantum dots and carbon spheres from pericarp

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Science China Chemistry 2015年第5期58卷 863-870页

作者： Wei Du Xiaoqian Xu Han Hao Rongmei Liu Di Zhang Feng Gao Qingyi Lu State Key Laboratory of Coordination Chemistry Nanjing National Laboratory of Microstructures Coordination Chemistry Institute Nanjing University Department of Materials Science and Engineering Nanjing University College of Biological and Chemical Engineering Anhui Polytechnic University

An economical idea was developed to synthesize fluorescent carbon quantum dots （CQDs） directly fl-om the refluxing extraction of orange pericarp via a hydrothermal technique. Hydrothermal temperatures and times were adjusted to control the particle sizes and the quantum yields of the obtained CQDs. The as-prepared carbon quantum dots showed narrow particle size distribution, good water solubility, and acceptable fluorescence lifetimes. Due to their high stability, these obtained carbon quantum dots have great application potential in nano-biotechnology. Furthermore, carbon spheres with uniform morphology and size can be easily obtained as the reaction byproducts of this green synthesis process.

关键词： carbon quantum dots carbon sphere green synthesis fluorescence

green synthesis of NiFe LDH/Ni foam at room temperature for highly efficient electrocatalytic oxygen evolution reaction

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Science China Materials 2019年第5期62卷 681-689页

作者： Hongchao Yang Changhong Wang Yejun Zhang Qiangbin Wang School of Nano Technology and Nano Bionics University of Science and Technology of China Key Laboratory of Nano-Bio Interface Division of Nanobiomedicine and i-Lab Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences

Clean energy technologies such as water splitting and fuel cells have been intensively pursued in the last decade for their free pollution. However, there is plenty of fossil energy consumed in the preparation of the catalysts,which results in a heavy pollution. Therefore, it is much desired but challenging to fabricate high-efficiency catalysts without extra energy input. Herein, we used a facile one-pot room-temperature method to synthesize a highly efficient electrocatalyst of nickel iron layered double hydroxide grown on Ni foam(NiFe LDH/NF) for oxygen evolution reaction(OER). The formation of the NiFe LDH follows a dissolutionprecipitation process, in which the acid conditions by hydrolysis of Fe^3+ combined with NO3^- could etch the NF to form Ni^2+. Then, the obtained Ni^2+ was co-precipitated with the hydrolysed Fe^3+ to in situ generate NiFe LDH on the NF. The NiFe LDH/NF exhibits excellent OER performance with a low potential of about 1.411 V vs. reversible hydrogen electrode(RHE) at a current density of 10 m A cm^-2, a small Tafel slope of 42.3 mV dec^-1 and a significantly low potential of ~1.452 V vs. RHE at 100 mA cm^-2 in 1 mol L^-1 KOH. Moreover, the material also keeps its original morphology and structure over 20 h. This energy-efficient strategy to synthesize NiFe LDH is highly promising for widespread application in OER catalyst industry.

关键词： green synthesis nickel iron layered double hydroxide room temperature electrocatalyst oxygen evolution reaction (OER)

green synthesis of pure and doped semiconductor nanoparticles of ZnS and CdS

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Transactions of Nonferrous Metals Society of China 2015年第10期25卷 3265-3270页

作者： K.MURALEEDHARAN Vijisha K.RAJAN V.M.ABDUL MUJEEB Department of Chemistry University of Calicut

Nanoparticles of pure and Cu/Ag-doped CdS and ZnS have been synthesized via chemical bath deposition without using any capping or toxic *** synthesis was carried out through a simple and less expensive green *** XRD result shows that both pure CdS and ZnS and their doped derivatives are of high crystalline with hexagonal packing *** average crystalline size of all nanoparticles was calculated using Debye-Scherrer *** crystalline size of nanoparticles of pure samples varied with that of the doped *** average crystalline sizes of all nanoparticles are found to be in the range of 5.5-2.2 nm for CdS（from pure to doped） and 4.3-3.4 nm for ZnS,*** band gap values obtained from UV-visible spectra are in the range of 3.5-2.1 e V for CdS and 3.3-2.7 e V for ZnS derivatives,*** FTIR spectral data give characteristic peaks for Cd—S,Cu—S,Ag—S and Zn—S bonds and confirm the formation of respective *** peaks corresponding to the microstructural formation are also *** FE-SEM images show the granular morphological structure for all the *** agglomeration size of the samples in the range of 10-50 nm for CdS：Cu and 50-100 nm for ZnS：Cu is observed.

关键词： chalcogenide ZnS CdS nanostructure semiconductor green synthesis catalytic properties