TY - JOUR
T1 - Electrochemistry of ATP-capped silver nanoparticles in layer-by-layer multilayer films
AU - Singh, Poonam
AU - Solomon, Virgil C.
AU - Buttry, Daniel
N1 - Funding Information:
Acknowledgments We thank the electron microscopy laboratory in the ASU School of Life Sciences Bioimaging Facility for providing access to the TEM facility. This material is based upon work supported by the National Science Foundation under Grant No. CHE-0957122.
PY - 2014/7
Y1 - 2014/7
N2 - Colloidal silver nanoparticles (Ag NPs) capped with adenosine triphosphate (ATP) were prepared using borohydride reduction of Ag+ in the presence of ATP. Subsequent characterization was done using transmission electron microscopy/high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, and non-contact atomic force microscopy (NcAFM) confirming the size and composition of the Ag NPs. This report focuses on two topics: (1) the change in NP size and properties as a function of molar ratios of Ag+ to ATP capping ligand to BH4 - reductant, and (2) the electrochemical behavior of the NPs in layer-by-layer (LbL) multilayer films. On the basis of electrostatic interaction between negatively charged phosphate groups on Ag NPs and positively charged poly(diallyldimethylammonium) hydrochloride, NPs were immobilized on 3-mercaptopropionic acid (MCP)-functionalized gold electrodes using LbL assembly method followed by characterization of the film using NcAFM. Furthermore, the redox chemistry for phase transformations of immobilized Ag NPs to AgCl or Ag2O in multilayer films was examined using cyclic voltammetry (CV) in NaOH and NaCl solutions. A non-linear increase of charge with an increase in the number of bilayers in the film was observed up to five layers. Underpotential deposition of Pb on multilayer film of Ag NPs confirmed the presence of Ag in multilayer films. The stability of the LbL film toward electrochemical cycling to higher potentials (i.e., +0.8 V) in NaOH solutions was evaluated.
AB - Colloidal silver nanoparticles (Ag NPs) capped with adenosine triphosphate (ATP) were prepared using borohydride reduction of Ag+ in the presence of ATP. Subsequent characterization was done using transmission electron microscopy/high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, and non-contact atomic force microscopy (NcAFM) confirming the size and composition of the Ag NPs. This report focuses on two topics: (1) the change in NP size and properties as a function of molar ratios of Ag+ to ATP capping ligand to BH4 - reductant, and (2) the electrochemical behavior of the NPs in layer-by-layer (LbL) multilayer films. On the basis of electrostatic interaction between negatively charged phosphate groups on Ag NPs and positively charged poly(diallyldimethylammonium) hydrochloride, NPs were immobilized on 3-mercaptopropionic acid (MCP)-functionalized gold electrodes using LbL assembly method followed by characterization of the film using NcAFM. Furthermore, the redox chemistry for phase transformations of immobilized Ag NPs to AgCl or Ag2O in multilayer films was examined using cyclic voltammetry (CV) in NaOH and NaCl solutions. A non-linear increase of charge with an increase in the number of bilayers in the film was observed up to five layers. Underpotential deposition of Pb on multilayer film of Ag NPs confirmed the presence of Ag in multilayer films. The stability of the LbL film toward electrochemical cycling to higher potentials (i.e., +0.8 V) in NaOH solutions was evaluated.
KW - Electrochemistry
KW - Layer-by-layer assembly
KW - Phase transformation
KW - Silver nanoparticles
KW - Underpotential deposition
UR - http://www.scopus.com/inward/record.url?scp=84902946550&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84902946550&partnerID=8YFLogxK
U2 - 10.1007/s11051-014-2496-x
DO - 10.1007/s11051-014-2496-x
M3 - Article
AN - SCOPUS:84902946550
SN - 1388-0764
VL - 16
JO - Journal of Nanoparticle Research
JF - Journal of Nanoparticle Research
IS - 7
M1 - 2496
ER -