Special Issue "Synthesis, Assembly and Functional Application of Nanomaterials in Microsystems"

A special issue of Micromachines (ISSN 2072-666X). This special issue belongs to the section "D:Materials and Processing".

Deadline for manuscript submissions: closed (10 October 2018)

Special Issue Editors

Guest Editor
Prof. Chih-hung (Alex) Chang

School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, OR 97331-4003, USA
Website | E-Mail
Phone: +1-541-737-8548
Interests: thin film transsitors; photovoltaics; integrated chemical systems; nanomaterials; phase equilibria
Guest Editor
Dr. Ki-Joong Kim

National Energy Technology Laboratory (NETL) / US Department of Energy (DOE), 626 Cochrans Mill Road, Pittsburgh, PA 15236, USA
E-Mail
Phone: +1-412-386-4526
Interests: nano energy; carbon sensors; metal organic framework; plasmonic nanoparticles

Special Issue Information

Dear Colleagues,

Microsystems are miniaturized devices which perform specific or combined functions for computation and information processing; sensing and actuation; testing and measurement; molecule and material processing. This special issue aims to showcase research papers, short communications, and review articles that focus on recent progress in synthesis, assembly and testing of nanomaterials using microsystems and the functional applications of nanomaterials in microsystems. The topics of interest include, but are not limited to:

The use of microfluidics to synthesize, assemble, purify and deliver nanomaterials, functional nanostructures, and nanostructured thin films.

The use of micromachines to manipulate, assemble, separate and fabricate nanomaterials, nanostructures, and nanostructured thin films.

The use of microsystems for nanomaterial characterizations e.g. MEMS-based mechanical testing.

Microsystems with integrated nanomaterials such as catalytic microreactors; electrochemical biosensors; neural prosthetics; gas micro-sensors; smart sensors/actuators for biomedical applications; and micro batteries.

Prof. Chih-hung (Alex) Chang
Dr. Ki-Joong Kim
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. Micromachines is an international peer-reviewed open access monthly 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 1400 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

  • Microsystem

  • Micromachines

  • Microfluidics

  • Microreactor

  • Nanomaterials

  • Nanoparticles

  • Nanostructures

  • Synthesis
  • Assembly

  • Purification

Published Papers (6 papers)

View options order results:
result details:
Displaying articles 1-6
Export citation of selected articles as:

Research

Open AccessArticle
Fabrication of Adhesive Resistance Surface with Low Wettability on Ti6Al4V Alloys by Electro-Brush Plating
Micromachines 2019, 10(1), 64; https://doi.org/10.3390/mi10010064
Received: 17 December 2018 / Revised: 10 January 2019 / Accepted: 15 January 2019 / Published: 18 January 2019
PDF Full-text (16556 KB) | HTML Full-text | XML Full-text
Abstract
Anti-adhesive Ni coatings with low wettability were successfully fabricated on Ti6Al4V substrates via an electro-brush plating method, and subsequently modified with a fluoroalkylsilane (FAS) film. The surface morphology, chemical compositions, and wettability of the as-prepared coatings were measured using scanning electron microscopy (SEM), [...] Read more.
Anti-adhesive Ni coatings with low wettability were successfully fabricated on Ti6Al4V substrates via an electro-brush plating method, and subsequently modified with a fluoroalkylsilane (FAS) film. The surface morphology, chemical compositions, and wettability of the as-prepared coatings were measured using scanning electron microscopy (SEM), X-ray diffractometer (XRD), Fourier transform infrared spectrophotometry (FTIR), and contact angle measurements. The results showed that the surface of Ti6Al4V substrate was endowed with flower-like structures. Each flower-like cluster was constituted by a large number of Ni ions. After surface modification of FAS, the as-prepared Ti6Al4V surface had a water contact angle as high as 151.5°, a sliding angle close to 2.1°, and a solid surface energy as low as 0.97 mJ/m2. Potentiodynamic polarization tests showed that the Ni coating could provide a stable corrosion protection. In addition, the effects of processing conditions, such as working voltage, relative velocity, electrolyte concentration, and processing time, were investigated. The mechanism of the adhesive resistance was proposed, and the low wettability of Ti6Al4V surfaces was explained by Cassie–Baxter model. As a result, it was necessary to reduce the fraction of the solid–liquid interface in order to achieve anti-adhesive surface. Full article
Figures

Figure 1

Open AccessArticle
Aluminum Patterned Electroplating from AlCl3–[EMIm]Cl Ionic Liquid towards Microsystems Application
Micromachines 2018, 9(11), 589; https://doi.org/10.3390/mi9110589
Received: 18 October 2018 / Accepted: 6 November 2018 / Published: 12 November 2018
PDF Full-text (11489 KB) | HTML Full-text | XML Full-text
Abstract
Electroplating process is being used to deposit a relatively thick film of metallic materials for various microsystems applications, such as for the wafer-level bonding sealing frame and as a thermal actuator. Recently, the Al electroplating process from ionic liquid has been an attractive [...] Read more.
Electroplating process is being used to deposit a relatively thick film of metallic materials for various microsystems applications, such as for the wafer-level bonding sealing frame and as a thermal actuator. Recently, the Al electroplating process from ionic liquid has been an attractive deposition method for anti-corrosion coatings. To extend the utilization of the film, in particular for microsystems application, a microstructure formation by patterned electroplating of Al from AlCl 3 –1-ethyl-3-methylimidazolium chloride ((EMIm)Cl) ionic liquid is investigated in this study. The influences of each deposition parameters to the electroplating process as well as the resulting surface morphology are evaluated. Electroplated Al deposits on both Au and Al seed layers are both studied. It is also found that a recurrent galvanic pulse plating process yields in a higher current efficiency. Finally, Al electroplating on a 2 µm-trenched 100 mm-wafer is also demonstrated. Full article
Figures

Figure 1

Open AccessArticle
Micromixing Study of a Clustered Countercurrent-Flow Micro-Channel Reactor and Its Application in the Precipitation of Ultrafine Manganese Dioxide
Micromachines 2018, 9(11), 549; https://doi.org/10.3390/mi9110549
Received: 9 October 2018 / Revised: 20 October 2018 / Accepted: 24 October 2018 / Published: 26 October 2018
PDF Full-text (2663 KB) | HTML Full-text | XML Full-text
Abstract
A clustered countercurrent-flow micro-channel reactor (C-CFMCR) has been assembled by the numbering-up of its single counterpart (S-CFMCR). Its micromixing performance was then studied experimentally using a competitive parallel reaction system, and the micromixing time was calculated as the micromixing performance index. It was [...] Read more.
A clustered countercurrent-flow micro-channel reactor (C-CFMCR) has been assembled by the numbering-up of its single counterpart (S-CFMCR). Its micromixing performance was then studied experimentally using a competitive parallel reaction system, and the micromixing time was calculated as the micromixing performance index. It was found that the micromixing time of C-CFMCR was ranged from 0.34 to 10 ms according to its numbering-up times and the operating conditions of the reactor, and it was close to that of S-CFMCR under the same operating conditions, demonstrating a weak scaling-up effect from S-CFMCR to C-CFMCR. The C-CFMCR was then applied to prepare ultrafine manganese dioxide in a continuous manner at varying micromixing time. It showed that the micromixing time had a major effect on the particle structure. More uniform and smaller MnO2 particles were obtained with intensified micromixing. By building a typical three electrode system to characterize their performance as a supercapacitor material, the MnO2 particles prepared by both S-CFMCR and C-CFMCR under optimal conditions displayed a specific capacitance of ~175 F·g−1 at the current density of 1 A·g−1, with a decline of ~10% after 500 charge-discharge cycles. This work showed that C-CFMCR will have a great potential for the continuous and large-scale preparation of ultrafine particles. Full article
Figures

Figure 1

Open AccessArticle
Characterization of Cotton Ball-like Au/ZnO Photocatalyst Synthesized in a Micro-Reactor
Micromachines 2018, 9(7), 322; https://doi.org/10.3390/mi9070322
Received: 20 May 2018 / Revised: 14 June 2018 / Accepted: 22 June 2018 / Published: 26 June 2018
PDF Full-text (5483 KB) | HTML Full-text | XML Full-text
Abstract
Noble metal/metal oxide nanostructures are an efficient system in photocatalysis. Continuous and scalable production of advanced particle systems will be a requirement for commercial-scale deployment for many applications, including photocatalysis. In this work, Au/ZnO structures were synthesized in a continuous flow micro-reactor at [...] Read more.
Noble metal/metal oxide nanostructures are an efficient system in photocatalysis. Continuous and scalable production of advanced particle systems will be a requirement for commercial-scale deployment for many applications, including photocatalysis. In this work, Au/ZnO structures were synthesized in a continuous flow micro-reactor at room temperature and the detailed characteristics of the product indicate a specific cotton ball-like core-shell microstructure that showcases specific advantages compared to traditional batch synthesis methods. The formation pathway of the core-shell Au/ZnO structures is discussed with the pH-dependent speciation diagram, and photocatalytic activity was assessed under simulated sunlight, demonstrating the enhanced performance of the cotton ball-like Au/ZnO microstructures in photocatalytic dye degradation. This work describes the application of microreaction technology in the continuous production of metal/metal oxide photocatalysts. Full article
Figures

Figure 1

Open AccessArticle
Micro Droplet Formation towards Continuous Nanoparticles Synthesis
Micromachines 2018, 9(5), 248; https://doi.org/10.3390/mi9050248
Received: 26 April 2018 / Revised: 12 May 2018 / Accepted: 15 May 2018 / Published: 18 May 2018
Cited by 4 | PDF Full-text (2148 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In this paper, micro droplets are generated in a microfluidic focusing contactor and then they move sequentially in a free-flowing mode (no wall contact). For this purpose, two different micro-flow glass devices (hydrophobic and hydrophilic) were used. During the study, the influence of [...] Read more.
In this paper, micro droplets are generated in a microfluidic focusing contactor and then they move sequentially in a free-flowing mode (no wall contact). For this purpose, two different micro-flow glass devices (hydrophobic and hydrophilic) were used. During the study, the influence of the flow rate of the water phase and the oil phase on the droplet size and size distribution was investigated. Moreover, the influence of the oil phase viscosity on the droplet size was analyzed. It was found that the size and size distribution of the droplets can be controlled simply by the aqueous phase flow rate. Additionally, 2D simulations to determine the droplet size were performed and compared with the experiment. Full article
Figures

Figure 1

Open AccessArticle
Capillary Rise of Nanostructured Microwicks
Micromachines 2018, 9(4), 153; https://doi.org/10.3390/mi9040153
Received: 10 February 2018 / Revised: 21 March 2018 / Accepted: 26 March 2018 / Published: 28 March 2018
PDF Full-text (25468 KB) | HTML Full-text | XML Full-text
Abstract
Capillarity refers to the driving force to propel liquid through small gaps in the absence of external forces, and hence enhanced capillary force has been pursued for various applications. In this study, flower like ZnO nanostructures are successfully deposited to enhance capillarity of [...] Read more.
Capillarity refers to the driving force to propel liquid through small gaps in the absence of external forces, and hence enhanced capillary force has been pursued for various applications. In this study, flower like ZnO nanostructures are successfully deposited to enhance capillarity of microwick structures that are specially designed to augment boiling heat transfer performance. Microreactor-assisted nanomaterial deposition, MANDTM, is employed with a flow cell to deposit the ZnO nanostructures on a large sized microwick (4.3 cm × 10.7 cm) with dual-channel configuration. A capillary rise experiment based on the mass gain method is first performed using water and ethanol (EtOH) as the working liquids to demonstrate the enhanced capillary force induced by the ZnO nanostructure on the microwick structure. It is found that the coating of ZnO nanostructure effectively propels the working fluids through the nano- or micro pores created from the ZnO nanostructure and consequently improves the capillary force. In order to investigate the wicking mechanism of the ZnO coated microwick structure, the capillary rise result based on height measurement was compared with analytical models. It is found that the gravity effect and viscous force play an important role in wicking rise of the coated wick structure. This study aims at demonstrating the capability of the integrated MAND process with a flow cell for producing a large scaled nanostructured surface, which eventually has a great potential for enhanced boiling heat transfer. Full article
Figures

Figure 1

Micromachines EISSN 2072-666X Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top