Papers by Sreekumar Kuriyedath
Prokofiev for their time and effort in serving in my dissertation committee. I thank Prof. Maroud... more Prokofiev for their time and effort in serving in my dissertation committee. I thank Prof. Maroudas for the opportunity to attend his group meetings which have always been a valuable learning experience. I would like to thank Prof. Prokofiev for his thoughtful criticism that provoked improvements in this work. I would also like to thank group members JoungMo Cho, Tracy Heckler, Jun Wang, Bing Mei and the recent members of the group for their company and help. I am thankful for having met some wonderful colleagues and friends in the department and outside. I am thankful for the company and help during my stay to Tejinder Singh, Mayur Valipa, Anurag Verma, Kedarnath Kolluri, Vivek Tomar, and George Sfyris. I would like to thank Prof. Yannis Kevrekidis who helped refine these ideas and gave useful suggestions and criticism which were invaluable to this work. I would like to acknowledge my thesis advisor Prof. Mountziaris, for being with me in this long journey. His company, always pleasant, also ensured that I kept on in this long journey and his patient attitude always kept me in good spirit. Thank you very much. My parents' love and many sacrifices afforded me this opportunity. I do not think I would ever be able to thank them, but I do hope to give them joy in the future. Thank you very much Amma and Accha.
Prokofiev for their time and effort in serving in my dissertation committee. I thank Prof. Maroud... more Prokofiev for their time and effort in serving in my dissertation committee. I thank Prof. Maroudas for the opportunity to attend his group meetings which have always been a valuable learning experience. I would like to thank Prof. Prokofiev for his thoughtful criticism that provoked improvements in this work. I would also like to thank group members JoungMo Cho, Tracy Heckler, Jun Wang, Bing Mei and the recent members of the group for their company and help. I am thankful for having met some wonderful colleagues and friends in the department and outside. I am thankful for the company and help during my stay to Tejinder Singh, Mayur Valipa, Anurag Verma, Kedarnath Kolluri, Vivek Tomar, and George Sfyris. I would like to thank Prof. Yannis Kevrekidis who helped refine these ideas and gave useful suggestions and criticism which were invaluable to this work. I would like to acknowledge my thesis advisor Prof. Mountziaris, for being with me in this long journey. His company, always pleasant, also ensured that I kept on in this long journey and his patient attitude always kept me in good spirit. Thank you very much. My parents' love and many sacrifices afforded me this opportunity. I do not think I would ever be able to thank them, but I do hope to give them joy in the future. Thank you very much Amma and Accha.
Prokofiev for their time and effort in serving in my dissertation committee. I thank Prof. Maroud... more Prokofiev for their time and effort in serving in my dissertation committee. I thank Prof. Maroudas for the opportunity to attend his group meetings which have always been a valuable learning experience. I would like to thank Prof. Prokofiev for his thoughtful criticism that provoked improvements in this work. I would also like to thank group members JoungMo Cho, Tracy Heckler, Jun Wang, Bing Mei and the recent members of the group for their company and help. I am thankful for having met some wonderful colleagues and friends in the department and outside. I am thankful for the company and help during my stay to Tejinder Singh, Mayur Valipa, Anurag Verma, Kedarnath Kolluri, Vivek Tomar, and George Sfyris. I would like to thank Prof. Yannis Kevrekidis who helped refine these ideas and gave useful suggestions and criticism which were invaluable to this work. I would like to acknowledge my thesis advisor Prof. Mountziaris, for being with me in this long journey. His company, always pleasant, also ensured that I kept on in this long journey and his patient attitude always kept me in good spirit. Thank you very much. My parents' love and many sacrifices afforded me this opportunity. I do not think I would ever be able to thank them, but I do hope to give them joy in the future. Thank you very much Amma and Accha.
Simulation of Quantum Dot Synthesis in Microemulsion Templates
ABSTRACT
Computational Studies of Semiconductor Nanocrystal Synthesis In Templating Media
aiche.confex.com
We have developed mesoscopic models that describe the synthesis of zinc selenide nanocrystals in ... more We have developed mesoscopic models that describe the synthesis of zinc selenide nanocrystals in microemulsions and liquid crystals [1-3]. The templates are formed by self assembly of a ternary system that includes a polar solvent, a non-polar solvent, and an amphiphilic block ...
Industrial & Engineering Chemistry Research, 2010
A Lattice Monte Carlo (LMC) simulation technique has been developed to describe the synthesis of ... more A Lattice Monte Carlo (LMC) simulation technique has been developed to describe the synthesis of a single semiconductor nanocrystal inside the droplets of a microemulsion. The LMC simulation can track the diffusion of a precursor, its irreversible reaction with a second precursor to form nuclei, and the diffusion and coalescence of the nuclei into clusters and eventually into a single particle. In this paper we compare two scenarios for forming a single nanocrystal. The first scenario involves very rapid (spontaneous) conversion of a precursor dispersed in the droplet to nuclei that diffuse and coalesce into a single particle. The second scenario involves diffusion of a precursor to the droplet interface where an irreversible reaction with a second precursor forms nuclei that subsequently diffuse into the droplet and coalesce. Simulations were performed describing the synthesis of ZnSe nanocrystals with diameters up to 7 nm, i.e., below the quantum confinement threshold of 9 nm for this material. Comparison of the time required for the formation of a single final particle in each of the two cases reveals that for particles smaller than ∼3.5 nm the formation times are nearly equal. For particles larger than 3.5 nm, the second process is completed faster than the first one. Analysis of intermediate cluster populations indicates that the formation of a larger "sweeper" cluster accelerates the rate of coalescence and is more effective when the nuclei are supplied gradually, as in the second process, compared to spontaneous nucleation throughout the domain. The kinetics of coalescence of an initially monodisperse population of nuclei in spherical domains of finite size were studied and generalized equations were obtained that describe the evolution of the number of different sizes as function of dimensionless time; this constitutes an extension to the classical analysis of coalescence of monodisperse aerosols in an infinite domain.
Lattice Monte Carlo Simulation of Semiconductor Nanocrystal Synthesis In Microemulsion Droplets
Langmuir, 2010
A lattice Monte Carlo model has been developed to describe the formation of a single semiconducto... more A lattice Monte Carlo model has been developed to describe the formation of a single semiconductor nanocrystal (quantum dot) inside a droplet of a microemulsion. The motivation stems from the need to understand the kinetics of quantum dot formation in microemulsion templates with minimal droplet-droplet coalescence. In these systems, a fixed amount of a reactant is dissolved in each droplet, and another reactant is supplied by diffusion through the interface. Nucleation is facilitated by a spontaneous reaction between the precursors at the droplet interface, and the coalescence of nuclei and clusters ultimately leads to the formation of a single particle. The size of the final particle is controlled by the concentration of the first reactant. A hard-sphere potential is used to describe cluster-cluster interactions. The overall particle formation time initially increases with final particle size, quickly passes through a maximum, and subsequently decreases due to the formation of large intermediate clusters apparently acting as effective collision partners to smaller ones. Studies of the evolution of intermediate cluster sizes provided mechanistic details of the final particle formation through cluster-cluster coalescence. A generalized dimensionless equation is obtained that relates the formation time of the final particle to its size for various droplet sizes and diffusivities of the first reactant and clusters. A parametric study reveals that the final particle formation time is more sensitive to changes in the cluster-cluster coalescence probability than in the probability of nucleation.
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Papers by Sreekumar Kuriyedath