Amir A. Farajian, Ph.D.
Professor
Department of Mechanical and Materials Engineering,
Wright State University, Dayton, Ohio 45435, USA
Office phone: (937) 775-2619
Nanoscience and nanoengineering with emphasis on computational modeling, sensors, materials for renewable energy, inelastic response, nano- and molecular-electronics, nanoelectromechanical systems, electronic and thermal quantum transports, as well as 2D nanomaterials processing and characterization. Some of the recent topics include:
Ab initio and multiscale characterization and design of materials
Coherent and incoherent quantum electronic and thermal transports
2D nanomaterials processing and multiscale atomic-based thermodynamics
Nanoelectronic-based electrochemical and electromechanical sensors
Nanostructured fluids: Phase transition and electrorheology
Ab initio diffusion in defected metals/alloys at various temperatures
Thermoelectric and photovoltaic applications of nanostructured materials
Diffusion in metals/alloys/ceramics and their failure/strengthening
Deformation and failure of metals, alloys, and ceramics are of utmost importance in applications such as aerospace engineering. Simulations provide accurate description of processes in these materials. In particular, ab initio energy barriers and diffusion properties can be determined. These lead to prediction of failure and strengthening mechanisms.
J. Mater. Eng. Perform. (2024)
Multiscale atomic-based thermodynamics
Thermodynamic analysis is essential for analyzing atomistic processes at physically relevant temperatures and length scalesfor many applications. Multiscale determination of different contributions to free energy, including entropy and internal energy, that is based on atomic description of the system has unique advantages compared to other approximations (e.g. continuum).
Nanomaterials for renewable energy applications
Engineering materials at the atomic and molecular scales can have significant effects on energy harvesting such as thermoelectric and photovoltaic applications. Quantum confinement effects in low-dimensional nanomaterials can enhance their efficiency.
2D nanomaterials exfoliation
Given the current status of graphene, a unique 2D material, and its applications, exploring methods of graphene mass-production is of paramount importance. Direct exfoliation of graphene from graphite, without the unwanted effects of oxidation and/or intercalation, provides large amounts of defect-free graphene nanoplatelets. Suitable surfactant choice is crucial for this purpose. Understanding the exfoliation process at the atomic/molecular scale is essential for production optimization.
Quantum electronic and thermal transports
Nanostructured materials provide the possibility of engineering material properties at nanometer length scale. This can be utilized to solve outstanding technological problems in various fields. Electronic and thermal transports at the nanometer scale are significantly affected by quantum effects. Quantum transport studies are used to design and characterize materials for, e.g., nanoelectronic and thermal management application.
Appl. Phys. Lett. 109, 173102 (2016)
Thin Solid Films 499, 269 (2006)
Phys. Rev. Lett. 82, 5084 (1999)
Nano- and molecular-electronics
As shrinking size of electronic components causes them to have nanometer length scales, transport properties (both electronic and thermal) are governed by the quantum mechanics. Of special interest are the finite temperature effects and electron-phonon interactions.
J. Phys. Chem. C. 117, 12815 (2013)
J. Phys.: Condens. Matter 23, 075301 (2011)
Nanotechnology 20, 015201 (2009)
J. Chem. Phys. 127, 024901 (2007)
Thin Solid Films 499, 269 (2006)
Nanotube Electronics; Physical Review Focus, June 22, 1999
Nanostructured fluids phase transition and electrorheology
Nanostructured fluids possess novel characteristics and immense potentials. Controlling phase transition in nanostructured fluids is a key to their application. Phase transition in nanotube suspensions, e.g., can be controlled by applying electric field. A wide range of applications can be considered, for example superior dampers, heat and charge transfer , as well as cancer therapy.
Phys. Rev. B 77, 205432 (2008)
Nanosensors
When the unique electronic and transport properties of nanoscale systems are combined with their affinity for various molecules, nanosensor functionality will be the natural result. Changes in electronic transport properties of nanotubes as a result of gas molecules adsorption, e.g., are shown to provide superior sensor potentials.
J. Phys. Chem. C. 117, 12815 (2013)
J. Phys.: Condens. Matter 25, 115303 (2013)
Appl. Phys. Lett. 92, 022103 (2008)
Hydrogen-containing nanocages
Hydrogen-containing nanocages provide novel solutions to the hydrogen storage problem, which is essential in using hydrogen as a renewable and clean source of energy. Simulating the properties of such systems requires accurate electronic structure and molecular dynamics methods.
Cover feature of Nano Letters, March 2008 issue, March 12, 2008
Featured in Nanowerk Nanotechnology Portal, Oct. 19, 2007
Featured in EurekAlert, March 20, 2008
Nanoelectromechanical systems
Mechanical properties of nanometer scale systems exhibit unique features which can be exploited for novel applications. Seamless and reversible bending of systems such as nanotubes can be used together with their transport properties in order to design
nanoelectromechanical sensors and switches.
J. Phys.: Condens. Matter 25, 115303 (2013)
Phys. Rev. B 67, 205423 (2003)
Nanostructured composites
Incorporating nanoparticles, nanotubes, nanoribbons, etc. within material matrices can significantly enhance their mechanical, transport and optical properties. Same kinds of significant changes occur in nanoscale systems when they are doped with individual atoms and ions or with atomic clusters. Applications include diverse fields such as nanomedicine, nanosensors, nanoelectronics, etc.
J. Phys. Chem. C. 116, 22916 (2012)
Chem. Phys. Lett. 511, 101 (2011)
Phys. Rev. B 78, 155427 (2008)
Phys. Rev. B 68, 075410 (2003)
J. Chem. Phys. 111, 2164 (1999)
Featured in the front page of Japanese newspaper Nikkan Kogyo Shimbun (Business and Technology), Nov. 21, 2001
Activated processes
Some of the most important processes which occur in nature or in labs are activated; i.e., they do not proceed without an activating force, as the reactants and products are separated by an energy barrier. Simulating such physical and chemical processes requires especial considerations, to effectively map their minute/hour time scales to the femtosecond/picosecond domain of accurate molecular dynamics studies.
Acta Materialia 222, 117357 (2022)
J. Chem. Phys. 115, 6401 (2001)