title: Ruthenium based metallopolymer grafted reduced graphene oxide as a new hybrid solar light harvester in polymer solar cells.
abstract: A new class of pyridyl benzimdazole based Ru complex decorated polyaniline assembly (PANI-Ru) was covalently grafted onto reduced graphene oxide sheets (rGO) via covalent functionalization approach. The covalent attachment of PANI-Ru with rGO was confirmed from XPS analysis and Raman spectroscopy. The chemical bonding between PANI-Ru and rGO induced the electron transfer from Ru complex to rGO via backbone of the conjugated PANI chain. The resultant hybrid metallopolymer assembly was successfully demonstrated as an electron donor in bulk heterojunction polymer solar cells (PSCs). A PSC device fabricated with rGO/PANI-Ru showed an utmost ~6 fold and 2 fold enhancement in open circuit potential (Voc) and short circuit current density (Jsc) with respect to the standard device made with PANI-Ru (i.e., without rGO) under the illumination of AM 1.5 G. The excellent electronic properties of rGO significantly improved the electron injection from PANI-Ru to PCBM and in turn the overall performance of the PSC device was enhanced. The ultrafast excited state charge separation and electron transfer role of rGO sheet in hybrid metallopolymer was confirmed from ultrafast spectroscopy measurements. This covalent modification of rGO with metallopolymer assembly may open a new strategy for the development of new hybrid nanomaterials for light harvesting applications.
authors.affiliation: SRM Research Institute, SRM University, Kattankulathur, Kancheepuram 603203 (D.t.), Tamil Nadu, India.
authors.forename: R
authors.initials: R
authors.lastname: Vinoth
authors.affiliation: SRM Research Institute, SRM University, Kattankulathur, Kancheepuram 603203 (D.t.), Tamil Nadu, India.
authors.forename: S Ganesh
authors.initials: SG
authors.lastname: Babu
authors.affiliation: Organic and Hybrid Solar Cell Group, National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012, India.
authors.forename: Vishal
authors.initials: V
authors.lastname: Bharti
authors.affiliation: Organic and Hybrid Solar Cell Group, National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012, India.
authors.forename: V
authors.initials: V
authors.lastname: Gupta
authors.affiliation: Research Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Naka-Ku, Hamamatsu, Shizuoka 432-8011, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Navaneethan
authors.affiliation: SRM Research Institute, SRM University, Kattankulathur, Kancheepuram 603203 (D.t.), Tamil Nadu, India.
authors.forename: S Venkataprasad
authors.initials: SV
authors.lastname: Bhat
authors.affiliation: Center for Materials Science and Nano Devices, Department of Physics, SRM University, Kattankulathur, Kancheepuram 603203 (D.t.), Tamil Nadu, India.
authors.forename: C
authors.initials: C
authors.lastname: Muthamizhchelvan
authors.affiliation: Department of Materials Engineering, Indian Institute of Science, Bangalore 560012, India.
authors.forename: Praveen C
authors.initials: PC
authors.lastname: Ramamurthy
authors.affiliation: Ultrafast Optoelectronics and Terahertz Photonics group, Physics of Energy Harvesting Division CSIR-National Physical Laboratory, New Delhi, 110012, India.
authors.forename: Chhavi
authors.initials: C
authors.lastname: Sharma
authors.affiliation: National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012, India.
authors.forename: Dinesh K
authors.initials: DK
authors.lastname: Aswal
authors.affiliation: Research Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Naka-Ku, Hamamatsu, Shizuoka 432-8011, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Hayakawa
authors.affiliation: SRM Research Institute, SRM University, Kattankulathur, Kancheepuram 603203 (D.t.), Tamil Nadu, India.
authors.forename: B
authors.initials: B
authors.lastname: Neppolian