TY - JOUR
T1 - Molecular Dynamics Simulations Suggest a Possible Role for NO in the Polyol Synthesis of Silver Nanostructures
AU - Da Silva, José Adriano
AU - Meneghetti, Mario Roberto
AU - Soares, Cláudio Manuel
PY - 2020
Y1 - 2020
N2 - Polyol synthesis allows the preparation of silver nanostructures with different well-controlled morphologies and opens a window to explore their potential in various emerging applications. Despite their success in controlling the size and shape of many noble-metal nanostructures, some fundamental aspects of this control during the synthesis remain unclear. In this paper, we used molecular dynamics (MD) simulations (three replications 1550 ns long) to represent a possible adsorption structure of poly(vinylpyrrolidone) (PVP) with an average molecular weight of 55,000 Da (PVP55) on an Ag(100) surface on ethylene glycol (EG) medium. The conditions employed in the simulations reproduce the PVP chain length and density reported experimentally. We found that the adsorbed PVP55 layer has a first polymer contact, with some degree of order, where interactions are mediated by carbonyl groups close to the Ag(100) face. In order to study the effects of the presence of AgNO3 and NO in the medium on PVP55, three sets of simulations were run comprising (i) one PVP55 molecule in pure EG and with (ii) 0.25 M AgNO3 or (iii) NO. These simulations showed that the PVP55 compacts in pure EG and in the presence of AgNO3 but expands in the presence of NO. This points at new insights into the roles of the PVP adsorption layer and PVP/AgNO3 ratio in polyol synthesis.
AB - Polyol synthesis allows the preparation of silver nanostructures with different well-controlled morphologies and opens a window to explore their potential in various emerging applications. Despite their success in controlling the size and shape of many noble-metal nanostructures, some fundamental aspects of this control during the synthesis remain unclear. In this paper, we used molecular dynamics (MD) simulations (three replications 1550 ns long) to represent a possible adsorption structure of poly(vinylpyrrolidone) (PVP) with an average molecular weight of 55,000 Da (PVP55) on an Ag(100) surface on ethylene glycol (EG) medium. The conditions employed in the simulations reproduce the PVP chain length and density reported experimentally. We found that the adsorbed PVP55 layer has a first polymer contact, with some degree of order, where interactions are mediated by carbonyl groups close to the Ag(100) face. In order to study the effects of the presence of AgNO3 and NO in the medium on PVP55, three sets of simulations were run comprising (i) one PVP55 molecule in pure EG and with (ii) 0.25 M AgNO3 or (iii) NO. These simulations showed that the PVP55 compacts in pure EG and in the presence of AgNO3 but expands in the presence of NO. This points at new insights into the roles of the PVP adsorption layer and PVP/AgNO3 ratio in polyol synthesis.
UR - http://www.scopus.com/inward/record.url?scp=85096054710&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.0c08338
DO - 10.1021/acs.jpcc.0c08338
M3 - Article
AN - SCOPUS:85096054710
SN - 1932-7447
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
ER -