Conformation of Capping Ligands on Nanoplates: Facet-Edge-Induced Disorder and Self-Assembly-Related Ordering Revealed by Sum Frequency Generation Spectroscopy.
Surface-curvature-amplified conformational disorder in alkyl capping ligands has been observed previously when the nanoparticle radii approach the ligand length. Herein, sum frequency generation studies on oleic-acid-capped nanoplates show that even on faceted surfaces with dimensions tens of times greater than the ligand length a significant proportion of gauche defects exist in the capping layer. The molecular disorder on the nanosized facets is attributed to a facet-edge effect, which is diminished when increasing the facet size or assembling the nanofacets side to side. This feature is further explored to probe the self-assembly dynamics of nanoplates.
†i-LAB, Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences, Suzhou 215123, P. R. China.|‡School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, P.R. China.
Hao
H
Zhang
†i-LAB, Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences, Suzhou 215123, P. R. China.
Fujin
F
Li
†i-LAB, Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences, Suzhou 215123, P. R. China.
Qingbo
Q
Xiao
†i-LAB, Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences, Suzhou 215123, P. R. China.
Hongzhen
H
Lin
capping ligands; conformational disorder; nanofacet; self-assembly; sum frequency generation