Concentration Effect of Reducing Agents on Green Synthesis of Gold Nanoparticles: Size, Morphology, and Growth Mechanism.
Under various concentration conditions of reducing agents during the green synthesis of gold nanoparticles (AuNPs), we obtain the various geometry (morphology and size) of AuNPs that play a crucial role in their catalytic properties. Through both theoretical and experimental approaches, we studied the relationship between the concentration of reducing agent (caffeic acid) and the geometry of AuNPs. As the concentration of caffeic acid increases, the sizes of AuNPs were decreased due to the adsorption and stabilizing effect of oxidized caffeic acids (OXCAs). Thus, it turns out that optimal concentration exists for the desired geometry of AuNPs. Furthermore, we investigated the growth mechanism for the green synthesis of AuNPs. As the caffeic acid is added and adsorbed on the surface of AuNPs, the aggregation mechanism and surface free energy are changed and consequently resulted in the AuNPs of various geometry.
National Creative Research Initiatives (NCRI) Center for Isogeometric Optimal Design, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-744, Republic of Korea.
Hyun-Seok
HS
Kim
College of Pharmacy, Inje University, 197 Inje-ro, Gimhae, 621-749, Republic of Korea.
Yu Seon
YS
Seo
Department of Chemical Engineering, University of Seoul, Seoul, 130-743, Republic of Korea.
Kyeounghak
K
Kim
Department of Chemical Engineering, University of Seoul, Seoul, 130-743, Republic of Korea.
Jeong Woo
JW
Han
College of Pharmacy, Inje University, 197 Inje-ro, Gimhae, 621-749, Republic of Korea.
Youmie
Y
Park
National Creative Research Initiatives (NCRI) Center for Isogeometric Optimal Design, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-744, Republic of Korea. secho@snu.ac.kr.
Seonho
S
Cho
Aggregation mechanism; Concentration of reducing agent; DFT calculation; Gold nanoparticle; Green synthesis; Molecular dynamics