title: Understanding the electron transfer process in ZnO-naphthol azobenzoic acid composites from photophysical characterisation.
abstract: Semiconductor nanoparticles surface modified with organic molecules capable of visible light absorption and effectively transferring the electrons to the catalytic sites have the potential to be good photocatalysts. ZnO nanoparticles of size ∼3 nm are grafted with two azonaphthols, one conjugated and the other non-conjugated. The photophysical properties of modified ZnO indicate an effective electron transfer from the conjugated azonaphthol to ZnO but not in the case of the non-conjugated molecule. It is also observed from lifetime studies that the conjugated molecule stabilises the defect sites on ZnO nanoparticles. It is possible that excited electrons from the conjugated molecule are transferred to specific defect sites in ZnO. This apparently does not occur in the non-conjugated molecule, bringing to focus the importance of the photophysical characteristics of organic modifiers in designing visible light active photocatalysts.
authors.affiliation: Catalysis and Inorganic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune - 411008, India. nr.devi@ncl.res.in and Academy of Scientific and Innovative Research (AcSIR), New Delhi, India.
authors.forename: Leena
authors.initials: L
authors.lastname: George
authors.affiliation: Catalysis and Inorganic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune - 411008, India. nr.devi@ncl.res.in.
authors.forename: Athira K
authors.initials: AK
authors.lastname: Kunhikannan
authors.affiliation: Academy of Scientific and Innovative Research (AcSIR), New Delhi, India and Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune, India.
authors.forename: Rajith
authors.initials: R
authors.lastname: Illathvalappil
authors.affiliation: Department of Chemistry, Savitribai Phule Pune University, Ganeshkhind Road, Pune 411007, India.
authors.forename: Divya
authors.initials: D
authors.lastname: Ottoor
authors.affiliation: Academy of Scientific and Innovative Research (AcSIR), New Delhi, India and Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune, India.
authors.forename: Sreekumar
authors.initials: S
authors.lastname: Kurungot
authors.affiliation: Catalysis and Inorganic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune - 411008, India. nr.devi@ncl.res.in and Academy of Scientific and Innovative Research (AcSIR), New Delhi, India.
authors.forename: R Nandini
authors.initials: RN
authors.lastname: Devi