Special Issue "Green Nanotechnology: The Latest Innovations, Knowledge Gaps, and Future Perspectives"

A special issue of Applied Sciences (ISSN 2076-3417). This special issue belongs to the section "Nanotechnology and Applied Nanosciences".

Deadline for manuscript submissions: closed (31 January 2021).

Special Issue Editors

Dr. Roberto Martins
E-Mail Website1 Website2
Guest Editor
CESAM – Centre for Environmental and Marine Studies and Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal
Interests: marine nanoecotoxicology; green nanotechnology R&D; “smart” engineered nanomaterials; environmental risk assessment
Dr. Olga Barbara Kaczerewska
E-Mail Website
Guest Editor
CICECO-Aveiro Institute of Materials and Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal
Interests: cationic surfactants; nanomaterials; controlled release applications; green chemistry

Special Issue Information

Dear Colleagues,

Nanotechnology is a key enabling technology bringing together chemists, biologists, physicians, and materials science engineers, among others. It has been proposed for addressing societal challenges due to the vast range of applications, such as on nanomedicine, food, nanoelectronics, energy, packaging, composite materials, coatings, construction, water treatment or environmental remediation. Not surprisingly, the use of nanostructured materials has been raising health and environmental safety concerns favoring the expansion of a sub-field dedicated to green and safe-by-design solutions. Green nanotechnology aims at developing solutions that minimize environmental and human health risks of nanomaterials during their lifetime through the replacement of toxic products or current processes through suitable eco-friendly alternatives. This Special Issue seeks innovative applications, products, technologies or processes beyond the state-of-the-art in any scientific green nanotechnology-related field as well as considerations in terms of future perspectives and identification of gap knowledges. Research on sustainable production of nanomaterials, novel safer-by-design technologies or (eco)toxicological assessment of novel nanomaterials is also welcome.

Dr. Roberto Martins
Dr. Olga Barbara Kaczerewska
Guest Editors

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 papers will be 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. Applied Sciences 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 2000 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

  • green nanotechnology
  • green chemistry
  • safety-by-design
  • sustainability
  • nanomaterials
  • nanoparticles
  • nanoecotoxicology
  • environmental risk assessment

Published Papers (5 papers)

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

Research

Open AccessArticle
Nanostructured Black Nickel Coating as Replacement for Black Cr(VI) Finish
Appl. Sci. 2021, 11(9), 3924; https://doi.org/10.3390/app11093924 - 26 Apr 2021
Viewed by 209
Abstract
This work compares different electrodeposition procedures to produce nickel black coatings as greener and less toxic alternatives to Cr(VI)-based coatings used in different applications. Nickel and nickel-plated brass served as substrates in studies with a Hull cell and polarization curves. After a set [...] Read more.
This work compares different electrodeposition procedures to produce nickel black coatings as greener and less toxic alternatives to Cr(VI)-based coatings used in different applications. Nickel and nickel-plated brass served as substrates in studies with a Hull cell and polarization curves. After a set of comparative experiments, the best electrodeposition procedure was further studied and optimized. Optimal conditions were found with a bath consisting of 75 g/L NiCl2·6H2O + 30 g/L NaCl and a current density of 0.143 A dm−2 applied for 5 min at room temperature. Furthermore, a pre-treatment with 18.5 vol.% of hydrochloric acid in water was found to be necessary to warrant good coating adhesion to the substrate. The black color is attributed to the development of a nanostructured surface that absorbs the incident light. Corrosion testing was performed in 0.5 M NaCl aqueous solution using electrochemical impedance spectroscopy (EIS) and polarization tests. Full article
Show Figures

Figure 1

Open AccessArticle
Synthesis of Silver Nanoparticles with Gemini Surfactants as Efficient Capping and Stabilizing Agents
Appl. Sci. 2021, 11(1), 154; https://doi.org/10.3390/app11010154 - 26 Dec 2020
Viewed by 458
Abstract
The scientific community has paid special attention to silver nanoparticles (AgNPs) in recent years due to their huge technological capacities, particularly in biomedical applications, such as antimicrobials, drug-delivery carriers, device coatings, imaging probes, diagnostic, and optoelectronic platforms. The most popular method of obtaining [...] Read more.
The scientific community has paid special attention to silver nanoparticles (AgNPs) in recent years due to their huge technological capacities, particularly in biomedical applications, such as antimicrobials, drug-delivery carriers, device coatings, imaging probes, diagnostic, and optoelectronic platforms. The most popular method of obtaining silver nanoparticles as a colloidal dispersion in aqueous solution is chemical reduction. The choice of the capping agent is particularly important in order to obtain the desired size distribution, shape, and dispersion rate of AgNPs. Gemini alkylammonium salts are named as multifunctional surfactants, and possess a wide variety of applications, which include their use as capping agents for metal nanoparticles synthesis. Because of the high antimicrobial activity of gemini surfactants, AgNPs stabilized by this kind of surfactant may possess unique and strengthened biocidal properties. The present paper presents the synthesis of AgNPs stabilized by gemini surfactants with hexadecyl substituent and variable structure of spacer, obtained via ecofriendly synthesis. UV-Vis spectroscopy and dynamic light scattering were used as analyzing tools in order to confirm physicochemical characterization of the AgNPs (characteristic UV-Vis bands, hydrodynamic diameter of NPs, polydispersity index (PDI)). Full article
Show Figures

Figure 1

Open AccessArticle
Can Encapsulation of the Biocide DCOIT Affect the Anti-Fouling Efficacy and Toxicity on Tropical Bivalves?
Appl. Sci. 2020, 10(23), 8579; https://doi.org/10.3390/app10238579 - 30 Nov 2020
Viewed by 565
Abstract
The encapsulation of the biocide DCOIT in mesoporous silica nanocapsules (SiNC) has been applied to reduce the leaching rate and the associated environmental impacts of coatings containing this biocide. This research aimed to evaluate the effects of DCOIT in both free and nanostructured [...] Read more.
The encapsulation of the biocide DCOIT in mesoporous silica nanocapsules (SiNC) has been applied to reduce the leaching rate and the associated environmental impacts of coatings containing this biocide. This research aimed to evaluate the effects of DCOIT in both free and nanostructured forms (DCOIT vs. SiNC-DCOIT, respectively) and the unloaded SiNC on different life stages of the bivalve Perna perna: (a) gametes (fertilization success), (b) embryos (larval development), and (c) juveniles mussels (byssus threads production and air survival after 72 h of aqueous exposure). The effects on fertilization success showed high toxicity of DCOIT (40 min-EC50 = 0.063 μg L−1), followed by SiNC-DCOIT (8.6 μg L−1) and SiNC (161 μg L−1). The estimated 48 h-EC50 of SiNC, DCOIT and SiNC-DCOIT on larval development were 39.8, 12.4 and 6.8 μg L−1, respectively. The estimated 72 h-EC50 for byssus thread production were 96.1 and 305.5 µg L−1, for free DCOIT and SiNC-DCOIT, respectively. Air survival was significantly reduced only for mussels exposed to free DCOIT. Compared to its free form, SiNC-DCOIT presented a balanced alternative between efficacy and toxicity, inhibiting efficiently the development of the target stage (larvae that is prone to settle) and satisfactorily preventing the juvenile attachment. Full article
Show Figures

Figure 1

Open AccessFeature PaperArticle
Gemini Surfactant as a Template Agent for the Synthesis of More Eco-Friendly Silica Nanocapsules
Appl. Sci. 2020, 10(22), 8085; https://doi.org/10.3390/app10228085 - 15 Nov 2020
Cited by 1 | Viewed by 887
Abstract
Silica mesoporous nanocapsules are a class of “smart” engineered nanomaterials (ENMs) applied in several fields. Recent studies have highlighted that they can exert deleterious effects into marine organisms, attributed to the use of the toxic cationic surfactant N-hexadecyl-N,N, [...] Read more.
Silica mesoporous nanocapsules are a class of “smart” engineered nanomaterials (ENMs) applied in several fields. Recent studies have highlighted that they can exert deleterious effects into marine organisms, attributed to the use of the toxic cationic surfactant N-hexadecyl-N,N,N-trimethylammonium bromide (CTAB) during the synthesis of ENMs. The present study reports the successful synthesis and characterization of novel gemini surfactant-based silica nanocapsules. The gemini surfactant 1,4-bis-[N-(1-dodecyl)-N,N-dimethylammoniummethyl]benzene dibromide (QSB2-12) was chosen as a more environmentally-friendly replacement of CTAB. Nanocapsules were characterized by scanning electron microscopy (SEM), Fourier-transformed infrared spectroscopy (FTIR), dynamic light scattering (DLS), thermogravimetric analysis (TGA) and N2 adsorption-desorption isotherms. Short-term exposure effects of new ENMs were evaluated in four marine species (Nannochloropsis gaditana, Tetraselmis chuii and Phaeodactylum tricornutum) and the microcrustacean (Artemia salina). The replacement of the commercial cationic surfactant by the gemini surfactant does not change the structure nor the environmental behaviour in seawater of the newly synthesised silica nanocontainers. Additionally, it is demonstrated that using gemini surfactants can reduce the toxicity of novel silica nanocapsules towards the tested marine species. As a result, environmentally-friendly ENMs can be obtained based on a safe-by-design approach, thereby fitting the concept of Green Chemistry. Full article
Show Figures

Graphical abstract

Open AccessArticle
Stearic Acid, Beeswax and Carnauba Wax as Green Raw Materials for the Loading of Carvacrol into Nanostructured Lipid Carriers
Appl. Sci. 2020, 10(18), 6267; https://doi.org/10.3390/app10186267 - 09 Sep 2020
Cited by 3 | Viewed by 561
Abstract
The use of lipid nanoparticles as drug delivery systems has been growing over recent decades. Their biodegradable and biocompatible profile, capacity to prevent chemical degradation of loaded drugs/actives and controlled release for several administration routes are some of their advantages. Lipid nanoparticles are [...] Read more.
The use of lipid nanoparticles as drug delivery systems has been growing over recent decades. Their biodegradable and biocompatible profile, capacity to prevent chemical degradation of loaded drugs/actives and controlled release for several administration routes are some of their advantages. Lipid nanoparticles are of particular interest for the loading of lipophilic compounds, as happens with essential oils. Several interesting properties, e.g., anti-microbial, antitumoral and antioxidant activities, are attributed to carvacrol, a monoterpenoid phenol present in the composition of essential oils of several species, including Origanum vulgare, Thymus vulgaris, Nigellasativa and Origanum majorana. As these essential oils have been proposed as the liquid lipid in the composition of nanostructured lipid carriers (NLCs), we aimed at evaluating the influence of carvacrol on the crystallinity profile of solid lipids commonly in use in the production of NLCs. Different ratios of solid lipid (stearic acid, beeswax or carnauba wax) and carvacrol were prepared, which were then subjected to thermal treatment to mimic the production of NLCs. The obtained binary mixtures were then characterized by thermogravimetry (TG), differential scanning calorimetry (DSC), small angle X-ray scattering (SAXS) and polarized light microscopy (PLM). The increased concentration of monoterpenoid in the mixtures resulted in an increase in the mass loss recorded by TG, together with a shift of the melting point recorded by DSC to lower temperatures, and the decrease in the enthalpy in comparison to the bulk solid lipids. The miscibility of carvacrol with the melted solid lipids was also confirmed by DSC in the tested concentration range. The increase in carvacrol content in the mixtures resulted in a decrease in the crystallinity of the solid bulks, as shown by SAXS and PLM. The decrease in the crystallinity of lipid matrices is postulated as an advantage to increase the loading capacity of these carriers. Carvacrol may thus be further exploited as liquid lipid in the composition of green NLCs for a range of pharmaceutical applications. Full article
Show Figures

Figure 1

Back to TopTop