title: Silicon-pyrene/perylene hybrids as molecular rectifiers.
abstract: We have synthesized two alkenyl (C-6 and C-11 chains) pyrenes and one alkenyl (C-11 chain) perylene as the σ-π systems, which were electro-grafted on H-terminated Si surfaces to form the respective monolayers. The I-V characteristics of the monolayers revealed pronounced rectification in forward bias with a maximum rectification ratio (RR) of 2.5 × 10(5) at 2.5 V for the C-6-pyrene 4b, 1000 at 1.5 V for the C-11-pyrene 4a and 3000-5000 at 1.75 V for the C-11-perylene 3. The higher RR of the devices containing 4b compared to those of 4a and 3 is possibly due to better alignment and packing of the 4b-monolayers on the Si substrate. The rectification was explained using the ab initio molecular-orbital calculations.
authors.affiliation: Bio-Organic Division, Bhabha Atomic Research Centre, Mumbai, India. kavitachemistry1@gmail.com schatt@barc.gov.in.
authors.forename: Kavita
authors.initials: K
authors.lastname: Garg
authors.forename: Chiranjib
authors.initials: C
authors.lastname: Majumder
authors.forename: Sandip K
authors.initials: SK
authors.lastname: Nayak
authors.forename: Dinesh K
authors.initials: DK
authors.lastname: Aswal
authors.forename: Shiv K
authors.initials: SK
authors.lastname: Gupta
authors.forename: Subrata
authors.initials: S
authors.lastname: Chattopadhyay
mesh_terms: D018625:Microscopy, Atomic Force; D010569:Perylene / Q000138:chemical synthesis / Q000737:chemistry*; D011721:Pyrenes / Q000138:chemical synthesis / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D011721:Pyrenes; D010569:Perylene; C030984:pyrene; D012825:Silicon