Articles by Nikolay Borodinov in JoVE
Электрораспылительная Отложение равномерной толщины Ge Spencer Novak1, Pao-Tai Lin2,3, Cheng Li4, Nikolay Borodinov1, Zhaohong Han5, Corentin Monmeyran5, Neil Patel5, Qingyang Du5, Marcin Malinowski4, Sasan Fathpour4, Chatdanai Lumdee4, Chi Xu4, Pieter G. Kik4, Weiwei Deng6, Juejun Hu7, Anuradha Agarwal7, Igor Luzinov1, Kathleen Richardson4 1Department of Materials Science and Engineering, Clemson University, 2Department of Materials Science and Engineering, Texas A&M University, 3Department of Electrical and Computer Engineering, Texas A&M University, 4College of Optics and Photonics, Center for Research and Education in Optics and Lasers (CREOL), University of Central Florida, 5Department of Materials Science and Engineering, Massachusetts Institute of Technology, 6Department of Mechanical Engineering, Virginia Polytechnic Institute, 7Microphotonics Center, Massachusetts Institute of Technology
Other articles by Nikolay Borodinov on PubMed
Kinetics of Evaporation and Gel Formation in Thin Films of Ceramic Precursors Langmuir : the ACS Journal of Surfaces and Colloids. Dec, 2014 | Pubmed ID: 25397585 Precursors derived from the hydrolysis of organic or inorganic salts have been widely used to produce ceramic coatings for a broad variety of applications. When applying the liquid precursors to the substrates, it is extremely challenging to control the film uniformity and homogeneity. The rate of solvent evaporation at different locations is different, causing the viscosity variation and flows in the film. There is very limited knowledge about the viscosity change in evaporating ceramic precursors. Therefore, it is crucial to understand the effect of evaporation on viscosity variation in thin films and droplets. We use magnetic rotational spectroscopy to study the time dependence of viscosity in mullite precursors. A correlation between the viscosity change and evaporation kinetics is revealed. This correlation was used to relate the change of viscosity to the concentration of mullite. A master curve relating viscosity to the mullite concentration was constructed and used to propose a possible scenario of the viscosity increase during solvent evaporation.
Label-free Water Sensors Using Hybrid Polymer-dielectric Mid-infrared Optical Waveguides ACS Applied Materials & Interfaces. Jun, 2015 | Pubmed ID: 25924561 A chip-scale mid-IR water sensor was developed using silicon nitride (SiN) waveguides coated with poly(glycidyl methacrylate) (PGMA). The label-free detection was conducted at λ=2.6-2.7 μm because this spectral region overlaps with the characteristic O-H stretch absorption while being transparent to PGMA and SiN. Through the design of a hybrid waveguide structure, we were able to tailor the mid-IR evanescent wave into the PGMA layer and the surrounding water and, consequently, to enhance the light-analyte interaction. A 7.6 times enhancement of sensitivity is experimentally demonstrated and explained by material integration engineering as well as waveguide mode analysis. Our sensor platform made by polymer-dielectric hybrids can be applied to other regions of the mid-IR spectrum to probe other analytes and can ultimately achieve a multispectral sensor on-a-chip.
Stability of Grafted Polymer Nanoscale Films Toward Gamma Irradiation ACS Applied Materials & Interfaces. Sep, 2015 | Pubmed ID: 26259102 The present article focuses on the influence of gamma irradiation on nanoscale polymer grafted films and explores avenues for improvements in their stability toward the ionizing radiation. In terms of applications, we concentrate on enrichment polymer layers (EPLs), which are polymer thin films employed in sensor devices for the detection of chemical and biological substances. Specifically, we have studied the influence of gamma irradiation on nanoscale poly(glycidyl methacrylate) (PGMA) grafted EPL films. First, it was determined that a significant level of cross-linking was caused by irradiation in pure PGMA films. The cross-linking is accompanied by the formation of conjugated ester, carbon double bonds, hydroxyl groups, ketone carbonyls, and the elimination of epoxy groups as determined by FTIR. Polystyrene, 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl, dimethylphenylsilanol, BaF2, and gold nanoparticles were incorporated into the films and were found to mitigate different aspects of the radiation damage.