title: Layer-by-layer deposited multilayer films of oligo(pyrenebutyric acid) and a perylene diimide derivative: structure and photovoltaic properties.
abstract: Multilayer films of oligo(pyrenebutyric acid) (OPB) and N,N'-bis(N,N-dimethylaminopropylaminopropyl)-3,4,9,10-perylenediimide (BDMAPAP-PDI) were successfully fabricated by layer-by-layer deposition. Multilayer growth was monitored by ultraviolet-visible (UV-vis) spectroscopy, fluorescence spectroscopy, ellipsometry, and atomic force microscopy (AFM). It was found that extraction was scarcely observed although both components (OPB and BDMAPAP-PDI) have low molecular weights and both electrostatic interactions and pi-pi stacking contributed to the multilayer deposition. The multilayers exhibit a rapid photocurrent response, and excitations of both OPB and BDMAPAP-PDI can lead to the effective charge dissociation. The incident photon to current conversion efficiency (IPCE) of the composite film with 5 bilayers was measured to be 1.29% at the absorption peak of BDMAPAP-PDI. Fluorescence quenching and photovoltaic conversion studies indicated that strong photoinduced charge transfer interactions occurred at the area of OPB/BDMAPAP-PDI heterojunction in the films, which strongly enhanced the photoresponse of the multilayer films.
authors.affiliation: Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, People's Republic of China.
authors.forename: Lu
authors.initials: L
authors.lastname: Zhao
authors.forename: Tai
authors.initials: T
authors.lastname: Ma
authors.forename: Hua
authors.initials: H
authors.lastname: Bai
authors.forename: Gewu
authors.initials: G
authors.lastname: Lu
authors.forename: Chun
authors.initials: C
authors.lastname: Li
authors.forename: Gaoquan
authors.initials: G
authors.lastname: Shi
mesh_terms: D007094:Imides / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D015394:Molecular Structure; D010569:Perylene / Q000031:analogs & derivatives* / Q000737:chemistry; D010777:Photochemistry; D011721:Pyrenes / Q000737:chemistry*; D012996:Solutions; D013053:Spectrophotometry
chemical_list: D007094:Imides; D011721:Pyrenes; D012996:Solutions; C521332:perylenediimide; C002218:1-pyrenebutyrate; D010569:Perylene