Browsing by Author "Minary-Jolandan, Majid"
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Item Alginate-Collagen Fibril Composite HydrogelBaniasadi, Mahmoud; Minary-Jolandan, MajidWe report on the synthesis and the mechanical characterization of an alginate-collagen fibril composite hydrogel. Native type I collagen fibrils were used to synthesize the fibrous composite hydrogel. We characterized the mechanical properties of the fabricated fibrous hydrogel using tensile testing; rheometry and atomic force microscope (AFM)-based nanoindentation experiments. The results show that addition of type I collagen fibrils improves the rheological and indentation properties of the hydrogel.Item Enhancement of the Electrical Properties of DNA Molecular Wires Through Incorporation of Perylenediimide DNA Base Surrogates(Wiley-vch Verlag, 2019-04-25) Lin, Kuo-Yao; Burke, A.; King, Nolan B.; Kahanda, Dimithree; Mazaheripour, A.; Bartlett, A.; Dibble, D. J.; McWilliams, Mark A.; Taylor, David W.; Jocson, J. -M; Minary-Jolandan, Majid; Gorodetsky, A. A.; Slinker, Jason D.; Lin, Kuo-Yao; King, Nolan B.; Kahanda, Dimithree; McWilliams, Mark A.; Taylor, David W.; Minary-Jolandan, Majid; Slinker, Jason D.DNA has long been viewed as a promising material for nanoscale electronics, in part due to its well-ordered arrangement of stacked, pi-conjugated base pairs. Within this context, a number of studies have investigated how structural changes, backbone modifications, or artificial base substitutions affect the conductivity of DNA. Herein, we present a comparative study of the electrical properties of both well-matched and perylene-3,4,9,10-tetracarboxylic diimide (PTCDI)-containing DNA molecular wires that bridge nanoscale gold electrodes. By performing current-voltage measurements for such devices, we find that the incorporation of PTCDI DNA base surrogates within our macromolecular constructs leads to an approximately 6-fold enhancement in the observed current levels. Together, these findings suggest that PTCDI DNA base surrogates may enable the preparation of designer DNA-based nanoscale electronic components. © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, WeinheimItem Fabrication and Characterization of Multifunctional Bio-Inspired Composites(2017-08) Xu, Zhe; Minary-Jolandan, MajidThis dissertation concentrates on a comprehensive study on bio-inspired (“Nacre”-like) composite materials. It involves the design and fabrication approaches and characterize properties of composite materials including meta-ceramic brick-and-mortar composites and piezo-polymer matrix ceramic reinforced composites. Hybrid composites of layered brittle-ductile constituents assembled in brick-and-mortar architecture are promising for applications requiring damage tolerance. Mostly, polymer mortars has been considered the ductile layer, however, low stiffness of polymers does not efficiently transfer the shear force between hard ceramic bricks. Theoretical models point to metals as a more efficient mortar layer. However, infiltration of metals into ceramic scaffold is non-trivial, given the low adhesion between metals and ceramics. We report on an alternative approach to assemble brick-and-mortar metal-ceramic composites by using electro-less plating of nickel on alumina micro-platelets, which are subsequently aligned by magnetic field, taking advantage of paramagnetic properties of nickel. The assembled nickelcoated ceramic scaffold is then sintered using spark plasma sintering (SPS). We report on materials and mechanical properties of the composite. The fabricated metal-ceramic composite shows a rising R-curve fracture behavior. The results show that this is a promising approach toward development of damage-tolerant metal-ceramic composites. Hybrid materials of inorganic-organic phases in which each phase provides different functionality are attractive candidates for achieving multi-functionality. Using a layer-by-layer approach, we fabricated sheets of piezoelectric polymer P(VDF-TrFE) reinforced by aligned sub-micron thick platelets of single crystal sapphire. The as-fabricated films were transparent and piezoelectric, exhibited ductility up to ~330%, and tensile toughness of up to 26 J/g. In addition, we investigated the effect of thermal annealing of the polymer on the crystallinity of the polymer phase and its effect on the mechanical and piezoelectric properties of the fabricated films. Thermal annealing resulted in improvement of the elastic modulus and piezoelectric properties of the films. PVDF and its co-polymers piezoelectric polymers in film and nanofiber forms are increasingly used for sensing, actuation and energy harvesting. Given the semi-crystalline structure of these polymers, their electromechanical coupling behavior changes with thermomechanical processing. This research reports on the evolution of the mechanical properties, piezoelectric properties and morphology of P(VDF-TrFE) piezoelectric polymer thin films fabricated by spin- coating during thermal annealing and drawing, studied via tensile test, polarized optical microscopy, X-ray diffraction, polarized FTIR, and piezoresponse force microscopy (PFM). The results show that annealing and drawing process result in 10 and 13 times improvement in the elastic modulus and ultimate strength of the films, respectively. In addition, the piezoelectric constant and electromechanical coupling improves by 30% and more than 17 times, respectively. These changes are accompanied by 65% increase in the percentage of the crystallinity of the semi-crystalline piezoelectric films.Item Investigation of Mechanical and Thermal Post-Processing on Morphology and Electro-Mechanical Properties of Electrospun Piezoelectric Nanofibers(2017-05) Baniasadi, Mahmoud; 0000-0002-2027-2383 (Baniasadi, M); Minary-Jolandan, MajidNanofibers are one dimensional nanomaterials with exceptional properties. Different types of materials and fabrication techniques could result in multifunctional nanofibers with broad applications. Ferroelectric polymers such as PVDF and its copolymers could be formed into nanofibers that exhibit piezoelectric and pyroelectric properties. Several fabrication methods are proposed to produce nanofibers. Electrospinning is a common nanofiber fabrication process with broad throughput from lab scale to industrial scale. Mechanical stretching and electric field poling could enhance the piezoelectric properties of piezoelectric materials. Therefore, electrospinning is a preferred technique for piezoelectric nanofibers fabrication, because a high stretching rate and strong electric field are applied to nanofibers during the processing due to the nature of the process. The electromechanical coupling factor is an important metric in measuring the performance of piezoelectric materials. This factor highly depends on piezoelectric coefficient and Young’s modulus of the materials. Post-processing techniques such as twisting and stretching as mechanical post-processing, and annealing as thermal treatment were used to enhance piezoelectric and mechanical properties. In this work, the conventional electrospinning method with rotating collector drum was used to produce aligned P(VDF-TrFE) nanofibers. Both mechanical and thermal post-processings were employed to enhance the electromechanical coupling factor through piezoelectric and Young’s modulus enhancement. Mechanical and piezoelectric properties of electrospun nanofibers were investigated in nano and macro scales through tensile and AFM-based nanoindentation tests. Piezoelectric response of nanofibers was studied by flexure test and PFM, in macro and nano scales, respectively. The evolution of molecular structure, orientation of polymer chains and crystalline phase transitions were investigated by spectroscopy, crystallography, and calorimetry methods, to explain the enhancements of material properties.Item Layered Metal Dichalcogenides Thin Films Deposited by Pulse Laser Deposition(2017-12) Serna Villacis, Martha Isabel; Quevedo-Lopez, Manuel A.; Minary-Jolandan, MajidLayered metal dichalcogenides (LMDs) have outstanding intrinsic properties and are considered potential candidate electronic materials for emerging devices in the fields of optoelectronics, piezoelectronics, and lately in spintronics. However, for the implementation of these materials on large scale applications, new synthesis methods that enable deposition with controlled area and geometry are needed. This work explores Pulsed Laser Deposition (PLD), as a new technique for the development of layered dichalcogenides materials. In particular, MoS2, SnSe2, and MoSe2 deposition parameters are explored, using materials characterization techniques such as X-ray photoelectron spectroscopy, Atomic Force Microscopy, Transmission Electron Microscopy, Raman Spectroscopy, Rutherford Backscattering Spectrometry, X-Ray diffraction, and in-situ Residual Gas Analysis – Mass Spectrometry. The structure, morphology and chemistry of each of the thin films is used to estimate the quality of the thin films. In addition, electrical characterization such as Hall effect measurements and the first SnSe2 PLD-grown/Silicon junction diodes are demonstrated.Item Low-Cost Manufacturing of Metal-Ceramic Composites through Electrodeposition of Metal into Ceramic Scaffold(Amer Chemical Soc, 2019-01) Huang, Jiacheng; Daryadel, Soheil; Minary-Jolandan, Majid; 0000-0003-2472-302X (Minary-Jolandan, M); Huang, Jiacheng; Daryadel, Soheil; Minary-Jolandan, MajidInfiltration of a molten metal phase into a ceramic scaffold to manufacture metal-ceramic composites often involves high temperature, high pressure, and expensive processes. Low-cost processes for fabrication of metal-ceramic composites can substantially increase their applications in various industries. In this article, electroplating (electrodeposition) as a low-cost, room-temperature process is demonstrated for infiltration of metal (copper) into a lamellar ceramic (alumina) scaffold. Estimation shows that this is a low energy consumption process. Characterization of mechanical properties showed that metal infiltration enhanced the flexural modulus and strength by more than 50% and 140%, respectively, compared to the pure lamellar ceramic. More importantly, metal infiltration remarkably enhanced the crack initiation and crack growth resistance by more than 230% and 510% compared to the lamellar ceramic. The electrodeposition process for development of metal-ceramic composites can be extended to other metals and alloys that can be electrochemically deposited, as a low-cost and versatile process.Item Multi-Physics Simulation of Metal Printing at Micro/Nanoscale Using Meniscus-Confined Electrodeposition: Effect of Nozzle Speed and Diameter(American Institute of Physics Inc, 2018-08-31) Morsali, Seyedreza; Daryadel, Soheil; Zhou, Zhong; Behroozfar, Ali; Baniasadi, Mahmoud; Moreno, Salvador; Qian, Dong; Minary-Jolandan, Majid; Morsali, Seyedreza; Daryadel, Soheil; Zhou, Zhong; Behroozfar, Ali; Baniasadi, Mahmoud; Moreno, Salvador; Qian, Dong; Minary-Jolandan, MajidMeniscus-confined electrodeposition (MCED) is a solution-based, room temperature process for 3D printing of metals at micro/nanoscale. In this process, a meniscus (liquid bridge or capillary) between a nozzle and a substrate governs the localized electrodeposition process, which involves multiple physics of electrodeposition, fluid dynamics, mass, and heat transfer. We have developed a multiphysics finite element (FE) model to investigate the effects of nozzle speed (v N) and nozzle diameter (D0) in the MCED process. The simulation results are validated with experimental data. Based on theoretical approach and experimental observation, the diameter of the deposited wire is in the range of 0.5-0.9 times of the nozzle diameter. The applicable range for vN for various nozzle diameters is computed. The results showed that the contribution of migration flux to total flux remains nearly constant (∼50%) for all values of pipette diameter in the range examined (100 nm-5 μm), whereas the contribution of diffusion and evaporation fluxes to total flux increase and decrease with the increasing pipette diameter, respectively. Results of this multiphysics study can be used to guide the experiment for optimal process conditions. © 2017 Author(s).Item Nanomechanical Imaging of Soft Samples in Liquid Using Atomic Force MicroscopyMinary-Jolandan, Majid; Yu, M. -FThe widely used dynamic mode atomic force microscopy (AFM) suffers severe sensitivity degradation and noise increase when operated in liquid. The large hydrodynamic drag between the oscillating AFM cantilever and the surrounding liquid overwhelms the dissipative tip-sample interaction forces that are employed for nanomechanical imaging. In this article, we show that the recently developed Trolling-Mode AFM based on a nanoneedle probe can resolve nanomechanical properties on soft samples in liquid, enabled by the significantly reduced hydrodynamic drag between the cantilever and the liquid. The performance of the method was demonstrated by mapping mechanical properties of the membrane of living HeLa cells.Item Scalable, Hydrophobic and Highly-Stretchable Poly(Isocyanurate-Urethane) Aerogels(Royal Society of Chemistry) Malakooti, Sadeq; Rostami, Saman; Churu, H. G.; Luo, Huiyang; Clark, Jenna; Casarez, Fabiola; Rettenmaier, Owen; Daryadel, Soheil; Minary-Jolandan, Majid; Sotiriou-Leventis, C.; Leventis, N.; Lu, Hongbing; Malakooti, Sadeq; Rostami, Saman; Luo, Huiyang; Clark, Jenna; Casarez, Fabiola; Rettenmaier, Owen; Daryadel, Soheil; Minary-Jolandan, Majid; Lu, HongbingScalable, low-density and flexible aerogels offer a unique combination of excellent mechanical properties and scalable manufacturability. Herein, we report the fabrication of a family of low-density, ambient-dried and hydrophobic poly(isocyanurate-urethane) aerogels derived from a triisocyanate precursor. The bulk densities ranged from 0.28 to 0.37 g cm⁻³ with porosities above 70% v/v. The aerogels exhibit a highly stretchable behavior with a rapid increase in the Young's modulus with bulk density (slope of log-log plot > 6.0). In addition, the aerogels are very compressible (more than 80% compressive strain) with high shape recovery rate (more than 80% recovery in 30 s). Under tension even at high strains (e.g., more than 100% tensile strain), the aerogels at lower densities do not display a significant lateral contraction and have a Poisson's ratio of only 0.22. Under dynamic conditions, the properties (e.g., complex moduli and dynamic stress-strain curves) are highly frequency- and rate-dependent, particularly in the Hopkinson pressure bar experiment where in comparison with quasi-static compression results, the properties such as mechanical strength were three orders of magnitude stiffer. The attained outcome of this work supports a basis on the understanding of the fundamental mechanical behavior of a scalable organic aerogel with potential in engineering applications including damping, energy absorption, and substrates for flexible devices.Item Toward Control of Microstructure in Microscale Additive Manufacturing of Copper Using Localized Electrodeposition(Wiley-VCH Verlag GmbH, 2019-01) Daryadel, Soheil; Behroozfar, Ali; Minary-Jolandan, Majid; Minary-Jolandan, MajidThe progress in microscale additive manufacturing (μ-AM) of metals requires engineering of the microstructure for various functional applications. In particular, achieving in situ control over the microstructure during 3D printing is critical to eliminate the need for post-processing and annealing. Recent reports have demonstrated the possibility of electrochemical μ-AM of nanotwinned metals, in which the presence of parallel arrays of twin boundaries (TBs) are known to enhance mechanical and electrical properties. For the first time, the authors report that the microstructure of metals printed using the microscale localized pulsed electrodeposition (L-PED) process can be controlled in situ during 3D-printing. In particular, the authors show that through electrochemical process parameters the density and the orientation of the TBs, as well as the grain size can be controlled. The results of the in situ SEM microcompression experiments on directly 3D-printed micro-pillars show that such control over microstructure directly correlates with the mechanical properties of the printed metal.