Green Synthesis of Nanomaterials

A special issue of Nanomaterials (ISSN 2079-4991).

Deadline for manuscript submissions: closed (15 April 2019) | Viewed by 69538

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editor

Special Issue Information

Dear Colleagues,

Nanomaterials possess astonishing physical and chemical properties. They have a key role in the development of novel and effective drugs, catalysts, sensors, and pesticides, to cite just a few examples. Notably, the synthesis of nanomaterials is usually achieved with chemical and physical methods needing the use of extremely toxic chemicals or high-energy inputs. To move towards more eco-friendly processes, researchers have recently focused on so-called “green synthesis”, where microbial, animal-, and plant-borne compounds can be used as cheap reducing and stabilizing agents to fabricate nanomaterials. Green synthesis routes are cheap, environmentally sustainable, and can lead to the fabrication of nano-objects with controlled size and shape—two key features determining their bioactivity. 

However, real-world applications of green-fabricated nanomaterials are largely unexplored. Besides, what do we really know about their non-target toxicity? Which are their main modes of action? What is their possible fate in the environment? In this framework, the present Special Issue will include articles by expert authorities on nanomaterials synthesis and applications. Special emphasis will be devoted to their impact on the environment and long-term toxicity.

Prof. Dr. Giovanni Benelli
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Nanomaterials is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2900 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • chronic toxicity
  • nanoparticles
  • nanopesticides
  • environmental applications
  • environmental fate
  • genotoxicity
  • insecticides
  • nanotoxicity
  • non-target effects
  • sub-lethal effects
  • antimicrobials
  • drug development
  • nanocarriers
  • catalysts
  • sensors

Published Papers (14 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Editorial

Jump to: Research, Review

3 pages, 190 KiB  
Editorial
Green Synthesis of Nanomaterials
by Giovanni Benelli
Nanomaterials 2019, 9(9), 1275; https://doi.org/10.3390/nano9091275 - 07 Sep 2019
Cited by 18 | Viewed by 3521
Abstract
Nanomaterials possess stunning physical and chemical properties [...] Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)

Research

Jump to: Editorial, Review

14 pages, 2587 KiB  
Article
Ionic Nanocomplexes of Hyaluronic Acid and Polyarginine to Form Solid Materials: A Green Methodology to Obtain Sponges with Biomedical Potential
by María Gabriela Villamizar-Sarmiento, Ignacio Moreno-Villoslada, Samuel Martínez, Annesi Giacaman, Victor Miranda, Alejandra Vidal, Sandra L. Orellana, Miguel Concha, Francisca Pavicic, Judit G. Lisoni, Lisette Leyton and Felipe A. Oyarzun-Ampuero
Nanomaterials 2019, 9(7), 944; https://doi.org/10.3390/nano9070944 - 29 Jun 2019
Cited by 14 | Viewed by 3165
Abstract
We report on the design, development, characterization, and a preliminary cellular evaluation of a novel solid material. This material is composed of low-molecular-weight hyaluronic acid (LMWHA) and polyarginine (PArg), which generate aqueous ionic nanocomplexes (INC) that are then freeze-dried to create the final [...] Read more.
We report on the design, development, characterization, and a preliminary cellular evaluation of a novel solid material. This material is composed of low-molecular-weight hyaluronic acid (LMWHA) and polyarginine (PArg), which generate aqueous ionic nanocomplexes (INC) that are then freeze-dried to create the final product. Different ratios of LMWHA/PArg were selected to elaborate INC, the size and zeta potential of which ranged from 100 to 200 nm and +25 to −43 mV, respectively. Turbidimetry and nanoparticle concentration analyses demonstrated the high capacity of the INC to interact with increasing concentrations of LMWHA, improving the yield of production of the nanostructures. Interestingly, once the selected formulations of INC were freeze-dried, only those comprising a larger excess of LMWHA could form reproducible sponge formulations, as seen with the naked eye. This optical behavior was consistent with the scanning transmission electron microscopy (STEM) images, which showed a tendency of the particles to agglomerate when an excess of LMWHA was present. Mechanical characterization evidenced low stiffness in the materials, attributed to the low density and high porosity. A preliminary cellular evaluation in a fibroblast cell line (RMF-EG) evidenced the concentration range where swollen formulations did not affect cell proliferation (93–464 µM) at 24, 48, or 72 h. Considering that the reproducible sponge formulations were elaborated following inexpensive and non-contaminant methods and comprised bioactive components, we postulate them with potential for biomedical purposes. Additionally, this systematic study provides important information to design reproducible porous solid materials using ionic nanocomplexes. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Figure 1

18 pages, 3955 KiB  
Article
Elucidating the Chemistry behind the Reduction of Graphene Oxide Using a Green Approach with Polydopamine
by Cláudia Silva, Frank Simon, Peter Friedel, Petra Pötschke and Cordelia Zimmerer
Nanomaterials 2019, 9(6), 902; https://doi.org/10.3390/nano9060902 - 21 Jun 2019
Cited by 40 | Viewed by 4608
Abstract
A new approach using X-ray photoelectron spectroscopy (XPS) was employed to give insight into the reduction of graphene oxide (GO) using a green approach with polydopamine (PDA). In this approach, the number of carbon atoms bonded to OH and to nitrogen in PDA [...] Read more.
A new approach using X-ray photoelectron spectroscopy (XPS) was employed to give insight into the reduction of graphene oxide (GO) using a green approach with polydopamine (PDA). In this approach, the number of carbon atoms bonded to OH and to nitrogen in PDA is considered and compared to the total intensity of the signal resulting from OH groups in polydopamine-reduced graphene oxide (PDA-GO) to show the reduction. For this purpose, GO and PDA-GO with different times of reduction were prepared and characterized by Raman Spectroscopy and XPS. The PDA layer was removed to prepare reduced graphene oxide (RGO) and the effect of all chemical treatments on the thermal and electrical properties of the materials was studied. The results show that the complete reduction of the OH groups in GO occurred after 180 min of reaction. It was also concluded that Raman spectroscopy is not well suited to determine if the reduction and restoration of the sp2 structure occurred. Moreover, a significant change in the thermal stability was not observed with the chemical treatments. Finally, the electrical powder conductivity decreased after reduction with PDA, increasing again after its removal. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Graphical abstract

16 pages, 3638 KiB  
Article
Characterization of Palladium Nanoparticles Produced by Healthy and Microwave-Injured Cells of Desulfovibrio desulfuricans and Escherichia coli
by Jaime Gomez-Bolivar, Iryna P. Mikheenko, Lynne E. Macaskie and Mohamed L. Merroun
Nanomaterials 2019, 9(6), 857; https://doi.org/10.3390/nano9060857 - 05 Jun 2019
Cited by 28 | Viewed by 3801
Abstract
Numerous studies have focused on the bacterial synthesis of palladium nanoparticles (bio-Pd NPs), via uptake of Pd (II) ions and their enzymatically-mediated reduction to Pd (0). Cells of Desulfovibrio desulfuricans (obligate anaerobe) and Escherichia coli (facultative anaerobe, grown anaerobically) were exposed to low-dose [...] Read more.
Numerous studies have focused on the bacterial synthesis of palladium nanoparticles (bio-Pd NPs), via uptake of Pd (II) ions and their enzymatically-mediated reduction to Pd (0). Cells of Desulfovibrio desulfuricans (obligate anaerobe) and Escherichia coli (facultative anaerobe, grown anaerobically) were exposed to low-dose radiofrequency (RF) radiation(microwave (MW) energy) and the biosynthesized Pd NPs were compared. Resting cells were exposed to microwave energy before Pd (II)-challenge. MW-injured Pd (II)-treated cells (and non MW-treated controls) were contacted with H2 to promote Pd(II) reduction. By using scanning transmission electron microscopy (STEM) associated with a high-angle annular dark field (HAADF) detector and energy dispersive X-ray (EDX) spectrometry, the respective Pd NPs were compared with respect to their mean sizes, size distribution, location, composition, and structure. Differences were observed following MWinjury prior to Pd(II) exposure versus uninjured controls. With D. desulfuricans the bio-Pd NPs formed post-injury showed two NP populations with different sizes and morphologies. The first, mainly periplasmically-located, showed polycrystalline Pd nano-branches with different crystal orientations and sizes ranging between 20 and 30 nm. The second NPpopulation, mainly located intracellularly, comprised single crystals with sizes between 1 and 5 nm. Bio-Pd NPs were produced mainly intracellularly by injured cells of E. coli and comprised single crystals with a size distribution between 1 and 3 nm. The polydispersity index was reduced in the bio-Pd made by injured cells of E. coli and D. desulfuricans to 32% and 39%, respectively, of the values of uninjured controls, indicating an increase in NP homogeneity of 30–40% as a result of the prior MWinjury. The observations are discussed with respect to the different locations of Pd(II)-reducing hydrogenases in the two organisms and with respect to potential implications for the catalytic activity of the produced NPs following injury-associated altered NP patterning. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Figure 1

17 pages, 4103 KiB  
Article
Development of Effective Lipase-Hybrid Nanoflowers Enriched with Carbon and Magnetic Nanomaterials for Biocatalytic Transformations
by Renia Fotiadou, Michaela Patila, Mohamed Amen Hammami, Apostolos Enotiadis, Dimitrios Moschovas, Kyriaki Tsirka, Konstantinos Spyrou, Emmanuel P. Giannelis, Apostolos Avgeropoulos, Alkiviadis Paipetis, Dimitrios Gournis and Haralambos Stamatis
Nanomaterials 2019, 9(6), 808; https://doi.org/10.3390/nano9060808 - 28 May 2019
Cited by 53 | Viewed by 4513
Abstract
In the present study, hybrid nanoflowers (HNFs) based on copper (II) or manganese (II) ions were prepared by a simple method and used as nanosupports for the development of effective nanobiocatalysts through the immobilization of lipase B from Pseudozyma antarctica. The hybrid [...] Read more.
In the present study, hybrid nanoflowers (HNFs) based on copper (II) or manganese (II) ions were prepared by a simple method and used as nanosupports for the development of effective nanobiocatalysts through the immobilization of lipase B from Pseudozyma antarctica. The hybrid nanobiocatalysts were characterized by various techniques including scanning electron microscopy (SEM), energy dispersion spectroscopy (EDS), X-ray diffraction (XRD), Raman spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The effect of the addition of carbon-based nanomaterials, namely graphene oxide and carbon nanotubes, as well as magnetic nanoparticles such as maghemite, on the structure, catalytic activity, and operational stability of the hybrid nanobiocatalysts was also investigated. In all cases, the addition of nanomaterials during the preparation of HNFs increased the catalytic activity and the operational stability of the immobilized biocatalyst. Lipase-based magnetic nanoflowers were effectively applied for the synthesis of tyrosol esters in non-aqueous media, such as organic solvents, ionic liquids, and environmental friendly deep eutectic solvents. In such media, the immobilized lipase preserved almost 100% of its initial activity after eight successive catalytic cycles, indicating that these hybrid magnetic nanoflowers can be applied for the development of efficient nanobiocatalytic systems. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Graphical abstract

16 pages, 3811 KiB  
Article
Eco-Friendly Method for Tailoring Biocompatible and Antimicrobial Surfaces of Poly-L-Lactic Acid
by Magdalena Aflori, Maria Butnaru, Bianca-Maria Tihauan and Florica Doroftei
Nanomaterials 2019, 9(3), 428; https://doi.org/10.3390/nano9030428 - 13 Mar 2019
Cited by 17 | Viewed by 2898
Abstract
In this study, a facile, eco-friendly route, in two steps, for obtaining of poly-L-lactic acid/chitosan-silver nanoparticles scaffolds under quiescent conditions was presented. The method consists of plasma treatment and then wet chemical treatment of poly-L-lactic acid (PLLA) films in a chitosan based-silver nanoparticles [...] Read more.
In this study, a facile, eco-friendly route, in two steps, for obtaining of poly-L-lactic acid/chitosan-silver nanoparticles scaffolds under quiescent conditions was presented. The method consists of plasma treatment and then wet chemical treatment of poly-L-lactic acid (PLLA) films in a chitosan based-silver nanoparticles solution (Cs/AgNp). The changes of the physical and chemical surface proprieties were studied using scanning electron microscopy (SEM), small angle X-Ray scattering (SAXS), Fourier transform infrared spectroscopy (FTIR) and profilometry methods. A certain combination of plasma treatment and chitosan-based silver nanoparticles solution increased the biocompatibility of PLLA films in combination with cell line seeding as well as the antimicrobial activity for gram-positive and gram-negative bacteria. The sample that demonstrated from Energy Dispersive Spectroscopy (EDAX) to have the highest amount of nitrogen and the smallest amount of Ag, proved to have the highest value for cell viability, demonstrating better biocompatibility and very good antimicrobial proprieties. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Graphical abstract

10 pages, 1847 KiB  
Communication
A Polyol-Mediated Fluoride Ions Slow-Releasing Strategy for the Phase-Controlled Synthesis of Photofunctional Mesocrystals
by Xianghong He, Yaheng Zhang, Yu Fu, Ning Lian and Zhongchun Li
Nanomaterials 2019, 9(1), 28; https://doi.org/10.3390/nano9010028 - 26 Dec 2018
Cited by 1 | Viewed by 2704
Abstract
There are only a few inorganic compounds that have evoked as much interest as sodium yttrium fluoride (NaYF4). Its extensive applications in various fields, including transparent displays, luminescence coding, data storage, as well as biological imaging, demand the precise tuning of [...] Read more.
There are only a few inorganic compounds that have evoked as much interest as sodium yttrium fluoride (NaYF4). Its extensive applications in various fields, including transparent displays, luminescence coding, data storage, as well as biological imaging, demand the precise tuning of the crystal phase. Controlling the emergence of the desired α-phase has so far remained a formidable challenge, especially via a simple procedure. Herein, we represented a polyol-assisted fluoride ions slow-release strategy for the rational control of pure cubic phase NaYF4 mesocrystals. The combination of fluorine-containing ionic liquid as a fluoride source and the existence of a polyalcohol as the reactive medium ensure the formation of uniform α-phase mesocrystallines in spite of a higher temperature and/or higher doping level. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Figure 1

19 pages, 7108 KiB  
Article
Green Synthesis of High Temperature Stable Anatase Titanium Dioxide Nanoparticles Using Gum Kondagogu: Characterization and Solar Driven Photocatalytic Degradation of Organic Dye
by Kothaplamoottil Sivan Saranya, Vinod Vellora Thekkae Padil, Chandra Senan, Rajendra Pilankatta, Kunjumon Saranya, Bini George, Stanisław Wacławek and Miroslav Černík
Nanomaterials 2018, 8(12), 1002; https://doi.org/10.3390/nano8121002 - 04 Dec 2018
Cited by 70 | Viewed by 6439
Abstract
The present study reports a green and sustainable method for the synthesis of titanium dioxide (TiO2) nanoparticles (NPs) from titanium oxysulfate solution using Kondagogu gum (Cochlospermum gossypium), a carbohydrate polymer, as the NPs formation agent. The synthesized TiO2 [...] Read more.
The present study reports a green and sustainable method for the synthesis of titanium dioxide (TiO2) nanoparticles (NPs) from titanium oxysulfate solution using Kondagogu gum (Cochlospermum gossypium), a carbohydrate polymer, as the NPs formation agent. The synthesized TiO2 NPs were categorized by techniques such as X-Ray Diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy analysis, Raman spectroscopy, scanning electron microscope- Energy-dispersive X-ray spectroscopy (SEM-EDX), Transmission electron microscopy (TEM), High-resolution transmission electron microscopy (HR-TEM), UV-visible spectroscopy, Brunauer-Emmett-Teller (BET) surface area and particle size analysis. Additionally, the photocatalytic actions of TiO2 NPs were assessed with regard to their ability to degrade an organic dye (methylene blue) from aqueous solution in the presence of solar light. Various parameters affecting the photocatalytic activity of the TiO2 NPs were examined, including catalyst loading, reaction time, pH value and calcination temperature of the aforementioned particles. This green synthesis method involving TiO2 NPs explores the advantages of inexpensive and non-toxic precursors, the TiO2 NPs themselves exhibiting excellent photocatalytic activity against dye molecules. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Graphical abstract

11 pages, 16194 KiB  
Article
From Hollow to Solid Carbon Spheres: Time-Dependent Facile Synthesis
by Wojciech Kukułka, Karolina Wenelska, Martyna Baca, Xuecheng Chen and Ewa Mijowska
Nanomaterials 2018, 8(10), 861; https://doi.org/10.3390/nano8100861 - 20 Oct 2018
Cited by 20 | Viewed by 5833
Abstract
Here, we report a facile route for obtaining carbon spheres with fully tunable shell thickness. Using a hard template in chemical vapor deposition (CVD), hollow carbon spheres, solid carbon spheres, and intermediate structures can be obtained with optimized process time. The resulting carbon [...] Read more.
Here, we report a facile route for obtaining carbon spheres with fully tunable shell thickness. Using a hard template in chemical vapor deposition (CVD), hollow carbon spheres, solid carbon spheres, and intermediate structures can be obtained with optimized process time. The resulting carbon spheres with particle diameters of ~400 nm, as well as a controllable shell thickness from 0 to 70 nm, had high Brunauer–Emmett–Teller (BET) specific surface area (up to 344.8 m2·g−1) and pore volume (up to 0.248 cm3·g−1). The sphere formation mechanism is also proposed. This simple and reproducible technique can deliver carbon materials for various applications, e.g., energy storage and conversion, adsorption, catalytic, biomedical, and environmental applications. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Figure 1

13 pages, 3874 KiB  
Article
Environmentally-Friendly Green Approach for the Production of Zinc Oxide Nanoparticles and Their Anti-Fungal, Ovicidal, and Larvicidal Properties
by Naif Abdullah Al-Dhabi and Mariadhas Valan Arasu
Nanomaterials 2018, 8(7), 500; https://doi.org/10.3390/nano8070500 - 06 Jul 2018
Cited by 131 | Viewed by 6362
Abstract
Green synthesis of nanoparticles can be an important alternative compared to conventional physio-chemical synthesis. We utilized Scadoxus multiflorus leaf powder aqueous extract as a capping and stabilizing agent for the synthesis of pure zinc oxide nanoparticles (ZnO NPs). Further, the synthesized ZnO NPs [...] Read more.
Green synthesis of nanoparticles can be an important alternative compared to conventional physio-chemical synthesis. We utilized Scadoxus multiflorus leaf powder aqueous extract as a capping and stabilizing agent for the synthesis of pure zinc oxide nanoparticles (ZnO NPs). Further, the synthesized ZnO NPs were subjected to various characterization techniques. Transmission electron microscope (TEM) analysis showed an irregular spherical shape, with an average particle size of 31 ± 2 nm. Furthermore, the synthesized ZnO NPs were tested against Aedes aegypti larvae and eggs, giving significant LC50 value of 34.04 ppm. Ovicidal activity resulted in a higher percentage mortality rate of 96.4 ± 0.24 at 120 ppm with LC50 value of 32.73 ppm. Anti-fungal studies were also conducted for ZnO NPs against Aspergillus niger and Aspergillus flavus, which demonstrated a higher inhibition rate for Aspergillus flavus compared to Aspergillus niger. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Figure 1

10 pages, 2113 KiB  
Article
“Chocolate” Gold Nanoparticles—One Pot Synthesis and Biocompatibility
by Neelika Roy Chowdhury, Allison J. Cowin, Peter Zilm and Krasimir Vasilev
Nanomaterials 2018, 8(7), 496; https://doi.org/10.3390/nano8070496 - 05 Jul 2018
Cited by 15 | Viewed by 6100
Abstract
The chemical synthesis of nanoparticles can involve and generate toxic materials. Here, we present for the first time, a one pot direct route to synthesize gold nanoparticles (AuNPs) using natural cacao extract as both a reducing and stabilizing agent. The nanoparticles were characterized [...] Read more.
The chemical synthesis of nanoparticles can involve and generate toxic materials. Here, we present for the first time, a one pot direct route to synthesize gold nanoparticles (AuNPs) using natural cacao extract as both a reducing and stabilizing agent. The nanoparticles were characterized by UV-visible spectroscopy (UV-VIS), dynamic light scattering (DLS), and transmission electron microscopy (TEM); and have excellent biocompatibility with human primary dermal fibroblasts. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Graphical abstract

18 pages, 7366 KiB  
Article
Effects of Sample Preparation on Particle Size Distributions of Different Types of Silica in Suspensions
by Rodrigo R. Retamal Marín, Frank Babick, Gottlieb-Georg Lindner, Martin Wiemann and Michael Stintz
Nanomaterials 2018, 8(7), 454; https://doi.org/10.3390/nano8070454 - 21 Jun 2018
Cited by 41 | Viewed by 6279
Abstract
The granulometric characterization of synthetic amorphous silica (SAS) nanomaterials (NMs) still demands harmonized standard operation procedures. SAS is produced as either precipitated, fumed (pyrogenic), gel and colloidal SAS and these qualities differ, among others, with respect to their state of aggregation and aggregate [...] Read more.
The granulometric characterization of synthetic amorphous silica (SAS) nanomaterials (NMs) still demands harmonized standard operation procedures. SAS is produced as either precipitated, fumed (pyrogenic), gel and colloidal SAS and these qualities differ, among others, with respect to their state of aggregation and aggregate strength. The reproducible production of suspensions from SAS, e.g., for biological testing purposes, demands a reasonable amount of dispersing energy. Using materials representative for each of the types of SAS, we employed ultrasonic dispersing (USD) at energy densities of 8–1440 J/mL and measured resulting particle sizes by dynamic light scattering and laser diffraction. In this energy range, USD had no significant impact on particle size distributions of colloidal and gel SAS, but clearly decreased the particle size of precipitated and fumed SAS. For high energy densities, we observed a considerable contamination of SAS suspensions with metal particles caused by abrasion of the sonotrode’s tip. To avoid this problem, the energy density was limited to 270 J/mL and remaining coarse particles were removed with size-selective filtration. The ultrasonic dispersion of SAS at medium levels of energy density is suggested as a reasonable compromise to produce SAS suspensions for toxicological in vitro testing. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Graphical abstract

18 pages, 4222 KiB  
Article
Facile and Robust Solvothermal Synthesis of Nanocrystalline CuInS2 Thin Films
by Anna Frank, Jan Grunwald, Benjamin Breitbach and Christina Scheu
Nanomaterials 2018, 8(6), 405; https://doi.org/10.3390/nano8060405 - 05 Jun 2018
Cited by 3 | Viewed by 3728
Abstract
This work demonstrates that the solvothermal synthesis of nanocrystalline CuInS2 thin films using the amino acid l-cysteine as sulfur source is facile and robust against variation of reaction time and temperature. Synthesis was carried out in a reaction time range of [...] Read more.
This work demonstrates that the solvothermal synthesis of nanocrystalline CuInS2 thin films using the amino acid l-cysteine as sulfur source is facile and robust against variation of reaction time and temperature. Synthesis was carried out in a reaction time range of 3–48 h (at 150 °C) and a reaction temperature range of 100–190 °C (for 18 h). It was found that at least a time of 6 h and a temperature of 140 °C is needed to produce pure nanocrystalline CuInS2 thin films as proven by X-ray and electron diffraction, high-resolution transmission electron microscopy, and energy-dispersive X-ray spectroscopy. Using UV-vis spectroscopy, a good absorption behavior as well as direct band gaps between 1.46 and 1.55 eV have been determined for all grown films. Only for a reaction time of 3 h and temperatures below 140 °C CuInS2 is not formed. This is attributed to the formation of metal ion complexes with l-cysteine and the overall slow assembly of CuInS2. This study reveals that the reaction parameters can be chosen relatively free; the reaction is completely nontoxic and precursors and solvents are rather cheap, which makes this synthesis route interesting for industrial up scaling. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Figure 1

Review

Jump to: Editorial, Research

31 pages, 1420 KiB  
Review
Green Micro- and Nanoemulsions for Managing Parasites, Vectors and Pests
by Lucia Pavoni, Roman Pavela, Marco Cespi, Giulia Bonacucina, Filippo Maggi, Valeria Zeni, Angelo Canale, Andrea Lucchi, Fabrizio Bruschi and Giovanni Benelli
Nanomaterials 2019, 9(9), 1285; https://doi.org/10.3390/nano9091285 - 09 Sep 2019
Cited by 115 | Viewed by 7031
Abstract
The management of parasites, insect pests and vectors requests development of novel, effective and eco-friendly tools. The development of resistance towards many drugs and pesticides pushed scientists to look for novel bioactive compounds endowed with multiple modes of action, and with no risk [...] Read more.
The management of parasites, insect pests and vectors requests development of novel, effective and eco-friendly tools. The development of resistance towards many drugs and pesticides pushed scientists to look for novel bioactive compounds endowed with multiple modes of action, and with no risk to human health and environment. Several natural products are used as alternative/complementary approaches to manage parasites, insect pests and vectors due to their high efficacy and often limited non-target toxicity. Their encapsulation into nanosystems helps overcome some hurdles related to their physicochemical properties, for instance limited stability and handling, enhancing the overall efficacy. Among different nanosystems, micro- and nanoemulsions are easy-to-use systems in terms of preparation and industrial scale-up. Different reports support their efficacy against parasites of medical importance, including Leishmania, Plasmodium and Trypanosoma as well as agricultural and stored product insect pests and vectors of human diseases, such as Aedes and Culex mosquitoes. Overall, micro- and nanoemulsions are valid options for developing promising eco-friendly tools in pest and vector management, pending proper field validation. Future research on the improvement of technical aspects as well as chronic toxicity experiments on non-target species is needed. Full article
(This article belongs to the Special Issue Green Synthesis of Nanomaterials)
Show Figures

Figure 1

Back to TopTop