title: Direct measurements of the interaction between pyrene and graphite in aqueous media by single molecule force spectroscopy: understanding the pi-pi interactions.
abstract: Pyrene derivatives can absorb onto the surface of carbon nanotubes and graphite particles through pi-pi interactions to functionalize these inorganic building blocks with organic surface moieties. Using single molecule force spectroscopy, we have demonstrated the first direct measurement of the interaction between pyrene and a graphite surface. In particular, we have connected a pyrene molecule onto an AFM tip via a flexible poly(ethylene glycol) (PEG) chain to ensure the formation of a molecular bridge. The pi-pi interaction between pyrene and graphite is thus indicated to be approximately 55 pN with no hysteresis between the desorption and adhesion forces.
authors.affiliation: Key Lab of Organic Optoelectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
authors.forename: Yiheng
authors.initials: Y
authors.lastname: Zhang
authors.forename: Chuanjun
authors.initials: C
authors.lastname: Liu
authors.forename: Weiqing
authors.initials: W
authors.lastname: Shi
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Wang
authors.forename: Liming
authors.initials: L
authors.lastname: Dai
authors.forename: Xi
authors.initials: X
authors.lastname: Zhang