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Title: Nanoscale Molecules Under Thermodynamic Control:" Digestive Ripening" or " Nanomachining"

Abstract

Overall Research Goals and Specific Objectives: Nanoscale materials are becoming ubiquitous in science and engineering, and are found widely in nature. However, their formation processes and uniquely high chemical reactivities are not understood well, indeed are often mysterious. Over recent years, a number of research teams have described nanoparticle synthesis, and aging, thermal treatment, or etching times have been mentioned. We have used the terms “digestive ripening” and “nanomachining” and have suggested that thermodynamics plays an important part in the size adjustment to monodisperse arrays being formed. Since there is scant theoretical understanding of digestive ripening, the overall goal in our research is to learn what experimental parameters (ligand used, temperature, solvent, time) are most important, how to control nanoparticle size and shape after initial crude nanoparticles have been synthesized, and gain better understanding of the chemical mechanism details. Specific objectives for the past twentynine months since the grant began have been to (1) Secure and train personnel;as of 2011, a postdoc Deepa Jose, female from the Indian Institute of Science in Bangalore, India; Yijun Sun, a second year graduate student, female from China; and Jessica Changstrom, female from the USA, GK12 fellow (program for enhancing teaching ability) are activelymore » carrying out research. (2) Find out what happens to sulfur bound hydrogen of thiol when it interacts with gold nanoparticles. Our findings are discussed in detail later. (3) Determine the effect of particle size, shape, and temperature on dodecyl thiol assited digestive ripening of gold nanoparticles. See our discussions later. (4) To understand in detail the ligand interaction in molecular clusters and nanoparticles (5) Determine the effect of chain length of amines on Au nanoparticle size under digestive ripening conditions (carbon chain length varied from 4-18). (6) Determine the catalytic activity of gold superlattices obtained by digestive ripening for oxidation of CO to CO2 at room temperature. (7) Determine the photocatalytic activity of metal nanoparticles like Au, Ag,Cu, and Pd supported on TiO2 toward photocatalytic hydrogen production.« less

Authors:
 [1]
  1. Kansas State Univ., Manhattan, KS (United States)
Publication Date:
Research Org.:
Kansas State Univ., Manhattan, KS (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Contributing Org.:
Kansas State University
OSTI Identifier:
1183569
Report Number(s):
SC0005159
KSU#EC9988/GOCH001897
DOE Contract Number:
SC0005159
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Nanotechnology, digestive ripening, etching, inorganic, thermal treatment, metals, metal oxides, metal sulfides

Citation Formats

Klabunde, Kenneth J. Nanoscale Molecules Under Thermodynamic Control:" Digestive Ripening" or " Nanomachining". United States: N. p., 2015. Web. doi:10.2172/1183569.
Klabunde, Kenneth J. Nanoscale Molecules Under Thermodynamic Control:" Digestive Ripening" or " Nanomachining". United States. doi:10.2172/1183569.
Klabunde, Kenneth J. Thu . "Nanoscale Molecules Under Thermodynamic Control:" Digestive Ripening" or " Nanomachining"". United States. doi:10.2172/1183569. https://www.osti.gov/servlets/purl/1183569.
@article{osti_1183569,
title = {Nanoscale Molecules Under Thermodynamic Control:" Digestive Ripening" or " Nanomachining"},
author = {Klabunde, Kenneth J.},
abstractNote = {Overall Research Goals and Specific Objectives: Nanoscale materials are becoming ubiquitous in science and engineering, and are found widely in nature. However, their formation processes and uniquely high chemical reactivities are not understood well, indeed are often mysterious. Over recent years, a number of research teams have described nanoparticle synthesis, and aging, thermal treatment, or etching times have been mentioned. We have used the terms “digestive ripening” and “nanomachining” and have suggested that thermodynamics plays an important part in the size adjustment to monodisperse arrays being formed. Since there is scant theoretical understanding of digestive ripening, the overall goal in our research is to learn what experimental parameters (ligand used, temperature, solvent, time) are most important, how to control nanoparticle size and shape after initial crude nanoparticles have been synthesized, and gain better understanding of the chemical mechanism details. Specific objectives for the past twentynine months since the grant began have been to (1) Secure and train personnel;as of 2011, a postdoc Deepa Jose, female from the Indian Institute of Science in Bangalore, India; Yijun Sun, a second year graduate student, female from China; and Jessica Changstrom, female from the USA, GK12 fellow (program for enhancing teaching ability) are actively carrying out research. (2) Find out what happens to sulfur bound hydrogen of thiol when it interacts with gold nanoparticles. Our findings are discussed in detail later. (3) Determine the effect of particle size, shape, and temperature on dodecyl thiol assited digestive ripening of gold nanoparticles. See our discussions later. (4) To understand in detail the ligand interaction in molecular clusters and nanoparticles (5) Determine the effect of chain length of amines on Au nanoparticle size under digestive ripening conditions (carbon chain length varied from 4-18). (6) Determine the catalytic activity of gold superlattices obtained by digestive ripening for oxidation of CO to CO2 at room temperature. (7) Determine the photocatalytic activity of metal nanoparticles like Au, Ag,Cu, and Pd supported on TiO2 toward photocatalytic hydrogen production.},
doi = {10.2172/1183569},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jun 04 00:00:00 EDT 2015},
month = {Thu Jun 04 00:00:00 EDT 2015}
}

Technical Report:

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