Optically Responsive Nanomaterials

A special issue of Nanomaterials (ISSN 2079-4991). This special issue belongs to the section "Nanophotonics Materials and Devices".

Deadline for manuscript submissions: closed (1 September 2022) | Viewed by 10381

Special Issue Editors

Centro de Química Estrutural, Department of Chemical Engineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
Interests: hybrid silica nanoparticles for imaging and theranostics; optical fluorescent sensors; systhesis of fluorescent functional dyes
Special Issues, Collections and Topics in MDPI journals
Centro de Química Estrutural, Associação do Instituto Superior Técnico para a Investigação e o Desenvolvimento, Instituto Superior Técnico, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
Interests: optically responsive molecular material; nonlinear material; carbon nanomaterials; organic dye; organic semiconductors; energy and charge transfer; charge photogeneration

Special Issue Information

Dear Colleagues,

This Special Issue is focused on recent developments in optically responsive nanomaterials. Nanomaterials can respond to light in unique ways, by emitting upshifted or downshifted photons with extraordinary efficiency, by enhancing the electromagnetic field at the surface, by frustrating light propagation within certain photonic band gaps, by releasing heat, by generating charges, etc. While in some nanomaterials understanding their optical properties is still a challenge, in others the tailoring of such properties towards specific applications is now the driving force of recent developments. Light-responsive nanomaterials find applications in diverse fields such as theranostics, solar light harvesting, and water treatment.

We aim to gather innovative and breakthrough contributions in the field to make this Issue a reference for those working in fundamental and applied research on optically actuated nanomaterials.

We welcome the submission of papers focused on the synthesis and design of nanomaterials that are responsive to light, as well as papers dedicated to tailoring the optical properties of nanomaterials towards specific applications. We want this Issue to reflect the plethora of nanomaterials that are responsive to light, as well as the diversity of strategies followed to improve their performance and their potential applications.

Prof. Dr. Carlos Baleizão
Dr. Ermelinda M.S. Maçôas
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 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

  • Synthesis of optical materials
  • Light-responsive nanomaterials
  • Optical properties of nanomaterials
  • Photocatalysis
  • Charge photogeneration
  • Photodynamic therapy
  • Photothermal effect
  • Plasmonic nanoparticles
  • Carbon nanomaterials
  • Silica nanoparticles
  • Metal nanoparticles
  • Nanocomposites
  • 2D nanomaterials
  • Semiconductor nanocrystals
  • Perovskite nanoparticles
  • Photonic nanomaterials

Published Papers (6 papers)

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

Research

16 pages, 2086 KiB  
Article
Photon–Phonon Atomic Coherence Interaction of Nonlinear Signals in Various Phase Transitions Eu3+: BiPO4
by Huanrong Fan, Faizan Raza, Irfan Ahmed, Muhammad Imran, Faisal Nadeem, Changbiao Li, Peng Li and Yanpeng Zhang
Nanomaterials 2022, 12(23), 4304; https://0-doi-org.brum.beds.ac.uk/10.3390/nano12234304 - 04 Dec 2022
Cited by 2 | Viewed by 1143
Abstract
We report photon–phonon atomic coherence (cascade- and nested-dressing) interaction from the various phase transitions of Eu3+: BiPO4 crystal. Such atomic coherence spectral interaction evolves from out-of-phase fluorescence to in-phase spontaneous four-wave mixing (SFWM) by changing the time gate. The dressing [...] Read more.
We report photon–phonon atomic coherence (cascade- and nested-dressing) interaction from the various phase transitions of Eu3+: BiPO4 crystal. Such atomic coherence spectral interaction evolves from out-of-phase fluorescence to in-phase spontaneous four-wave mixing (SFWM) by changing the time gate. The dressing dip switch and three dressing dips of SFWM result from the strong photon–phonon destructive cross- and self-interaction for the hexagonal phase, respectively. More phonon dressing results in the destructive interaction, while less phonon dressing results in the constructive interaction of the atomic coherences. The experimental measurements of the photon–phonon interaction agree with the theoretical simulations. Based on our results, we proposed a model for an optical transistor (as an amplifier and switch). Full article
(This article belongs to the Special Issue Optically Responsive Nanomaterials)
Show Figures

Figure 1

22 pages, 16582 KiB  
Article
Towards the Configuration of a Photoelectrocatalytic Reactor: Part 2—Selecting Photoreactor Flow Configuration and Operating Variables by a Numerical Approach
by Daniel Borrás-Jiménez, Wilber Silva-López and César Nieto-Londoño
Nanomaterials 2022, 12(17), 3030; https://0-doi-org.brum.beds.ac.uk/10.3390/nano12173030 - 31 Aug 2022
Viewed by 1115
Abstract
This work aims to select a photoreactor flow configuration and operational conditions that maximize the Photocatalytic Space-time Yield in a photoelectrocatalytic reactor to degrade Reactive Red 239 textile dye. A numerical study by Computational Fluid Dynamics (CFD) was carried out to model the [...] Read more.
This work aims to select a photoreactor flow configuration and operational conditions that maximize the Photocatalytic Space-time Yield in a photoelectrocatalytic reactor to degrade Reactive Red 239 textile dye. A numerical study by Computational Fluid Dynamics (CFD) was carried out to model the phenomena of momentum and species transport and surface reaction kinetics. The photoreactor flow configuration was selected between axial (AF) and tangential (TF) inlet and outlet flow, and it was found that the TF configuration generated a higher Space-time Yield (STY) than the AF geometry in both laminar and turbulent regimes due to the formation of a helical movement of the fluid, which generates velocity in the circumferential and axial directions. In contrast, the AF geometry generates a purely axial flow. In addition, to maximize the Photocatalytic Space-time Yield (PSTY), it is necessary to use solar radiation as an external radiation source when the flow is turbulent. In conclusion, the PSTY can be maximized up to a value of 45 g/day-kW at an inlet velocity of 0.2 m/s (inlet Reynolds of 2830), solar radiation for external illumination, and internal illumination by UV-LEDs of 14 W/m2, using a photoreactor based on tangent inlet and outlet flow. Full article
(This article belongs to the Special Issue Optically Responsive Nanomaterials)
Show Figures

Figure 1

19 pages, 3589 KiB  
Article
Saturated Emission States in Fluorescent Nanostructured Media: The Role of Competition between the Stimulated Emission and Radiation Losses in the Local Emitters of Fluorescence
by Dmitry Zimnyakov, Sergey Volchkov, Leonid Kochkurov and Alexander Dorogov
Nanomaterials 2022, 12(14), 2450; https://0-doi-org.brum.beds.ac.uk/10.3390/nano12142450 - 17 Jul 2022
Viewed by 1194
Abstract
A fundamental limitation of the spectral response of laser-pumped fluorescent nanostructured media was considered in terms of a probabilistic model establishing the relationship between the enhancement factor of a spectral quality and characteristic propagation and amplification scales of pump light and fluorescence in [...] Read more.
A fundamental limitation of the spectral response of laser-pumped fluorescent nanostructured media was considered in terms of a probabilistic model establishing the relationship between the enhancement factor of a spectral quality and characteristic propagation and amplification scales of pump light and fluorescence in the medium. It was shown that the minimum spectral width of fluorescent response of the pumped medium is limited by competition between the stimulated emission and radiation losses in microscopic fluorescence emitters associated with the speckles randomly modulating the pumping light field. Theoretical results were compared to the experimental data on the spectral properties of the fluorescent response of laser-pumped nanostructured “anatase nanoparticles—dye solutions” systems with various structural and optical properties. Rhodamine 6G and 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM) were applied as fluorescent components in the examined systems with various scatter volume fractions, which were pumped by pulse-periodic laser radiation with various intensities at 532 nm. Comparison showed a fair agreement between the theoretical and experimental results. Full article
(This article belongs to the Special Issue Optically Responsive Nanomaterials)
Show Figures

Figure 1

25 pages, 23442 KiB  
Article
Towards the Configuration of a Photoelectrocatalytic Reactor: Part 1—Determination of Photoelectrode Geometry and Optical Thickness by a Numerical Approach
by Daniel Borrás-Jiménez, Wilber Silva-López and César Nieto-Londoño
Nanomaterials 2022, 12(14), 2385; https://0-doi-org.brum.beds.ac.uk/10.3390/nano12142385 - 12 Jul 2022
Cited by 1 | Viewed by 1539
Abstract
Photoelectrocatalysis has been highlighted as a tertiary wastewater treatment in the textile industry due to its high dye mineralisation capacity. However, design improvements are necessary to overcome photo-reactors limitations. The present work proposes a preliminary configuration of a photoelectrocatalytic reactor to degrade Reactive [...] Read more.
Photoelectrocatalysis has been highlighted as a tertiary wastewater treatment in the textile industry due to its high dye mineralisation capacity. However, design improvements are necessary to overcome photo-reactors limitations. The present work proposes a preliminary configuration of a photoelectrocatalytic reactor to degrade Reactive Red 239 (RR239) textile dye, using computational fluid dynamics (CFD) to analyse the mass transfer rate, radiation intensity loss (RIL), and its effect on kinetics degradation, over a photoelectrode based on a TiO2 nanotube. A study to increase the space-time yield (STY) was carried out through mass transfer rate and kinetic analysis, varying the optical thickness (δ) between the radiation entrance and the photocatalytic surface, photoelectrode geometry, inlet flow rate, and the surface radiation intensity. The RIL was determined using a 1D Beer–Lambert-based model, and an extinction coefficient experimentally determined by UV-Vis spectroscopy. The results show that in RR239 solutions below concentrations of 6 mg/L, a woven mesh photoelectrode and an optimal optical thickness δ of 1 cm is enough to keep the RIL below 15% and maximise the mass transfer and the STY in around 110 g/m3-day. Full article
(This article belongs to the Special Issue Optically Responsive Nanomaterials)
Show Figures

Figure 1

12 pages, 3079 KiB  
Article
Graphene Quantum Dots and Phthalocyanines Turn-OFF-ON Photoluminescence Nanosensor for ds-DNA
by Ana M. Santiago, Carla I. M. Santos, Leandro M. O. Lourenço, Inês F. A. Mariz, João P. C. Tomé and Ermelinda Maçôas
Nanomaterials 2022, 12(11), 1892; https://0-doi-org.brum.beds.ac.uk/10.3390/nano12111892 - 31 May 2022
Cited by 4 | Viewed by 1818
Abstract
Supramolecular hybrids of graphene quantum dots (GQDs) and phthalocyanine (Pc) dyes were studied as turn-OFF-ON photoluminescence nanosensors for detection of ds-DNA. Pcs with four (Pc4) and eight (Pc8) positive charges were selected to interact with negatively charged GQDs. The photoluminescence of the GQDs [...] Read more.
Supramolecular hybrids of graphene quantum dots (GQDs) and phthalocyanine (Pc) dyes were studied as turn-OFF-ON photoluminescence nanosensors for detection of ds-DNA. Pcs with four (Pc4) and eight (Pc8) positive charges were selected to interact with negatively charged GQDs. The photoluminescence of the GQDs was quenched upon interaction with the Pcs, due to the formation of non-emissive complexes. In the presence of ds-DNA, the Pcs interacted preferentially with the negatively charged ds-DNA, lifting the quenching effect over the photoluminescence of the GQDs and restoring their emission intensity. The best performance as a sensor of ds-DNA was registered for the GQD-Pc8, with a limit of detection (LOD) in the picomolar range. The LOD for GQD-Pc8 was more than one order of magnitude lower and its sensitivity was about a factor of three higher than that of the analogue GQD-Pc4 nanosensor. The sensitivity and selectivity of this simple GQD-Pc8 nanosensor is comparable to those of the more sophisticated carbon-based nanosensors for DNA reported previously. Full article
(This article belongs to the Special Issue Optically Responsive Nanomaterials)
Show Figures

Graphical abstract

15 pages, 2393 KiB  
Article
A Fluorescent Nanosensor for Silver (Ag+) and Mercury (Hg2+) Ions Using Eu (III)-Doped Carbon Dots
by Cátia Correia, José Martinho and Ermelinda Maçôas
Nanomaterials 2022, 12(3), 385; https://0-doi-org.brum.beds.ac.uk/10.3390/nano12030385 - 25 Jan 2022
Cited by 10 | Viewed by 2868
Abstract
Carbon dots doped with Eu3+ ions (Eu-Cdots) were prepared by a hydrothermal treatment, using citric acid and urea as precursors and Eu (NO3)3 as a europium source. The Eu3+ ions are strongly coordinated with the carboxylate groups at [...] Read more.
Carbon dots doped with Eu3+ ions (Eu-Cdots) were prepared by a hydrothermal treatment, using citric acid and urea as precursors and Eu (NO3)3 as a europium source. The Eu3+ ions are strongly coordinated with the carboxylate groups at the surface of the Cdots and incorporated within the nanographene network in the carbon core. Vibrational spectroscopy provides evidence of such interaction with identification of bands assigned to the stretching of the Eu-O bond. Eu3+ doped Cdots have larger diameters then undoped Cdots, but they are divided into smaller domains of sp2 carbon. The UV-vis excitation spectrum provides evidence of energy transfer from the Cdots to the Eu3+. The luminescence spectrum shows the characteristic sharp peaks of Eu3+ in the red part of the visible spectrum and a broad emission of Cdots centered at 450 nm. The luminescence of the Cdots is strongly quenched by Hg2+ and Ag+, but not by other cations. The quenching mechanism differs significantly depending on the nature of the ion. Both the blue emission of Cdots and the red emission of Eu3+ are quenched in the presence of Hg2+ while only the emission of the Cdots is affected by the presence of Ag+. A ratiometric sensor can be built using the ratio of luminescence intensities of the Cdots to the Eu3+ peaks. Full article
(This article belongs to the Special Issue Optically Responsive Nanomaterials)
Show Figures

Graphical abstract

Back to TopTop