Benzodithiophene-thiophene-based photovoltaic polymers with different side-chains
摘要:
A series of benzodithiophene-thiophene-based alternating copolymers were synthesized with different side-chains, and their photovoltaic characteristics were examined. The choice of solubilizing side-chains influences significantly the chain conformation, frontier orbital energy levels, intermolecular organization, and the resulting optical, morphological, and photovoltaic properties. The incorporation of an e-withdrawing carbonyl group in the side-chain decreased the highest occupied molecular orbital (HOMO, ca. -5.4 eV) level and improved the chain planarity through intrachain hydrogen bonding. The shortest - stacking distance (3.72 angstrom) was also measured for the alkylcarbonyl-substituted BDTCOT:PC71BM blended film by two dimensional grazing incidence X-ray scattering. With compared to other polymers, the BDTCOT:PC71BM device showed a substantially improved open-circuit voltage and short-circuit current density, leading to a 4.66% power conversion efficiency. The side-chains need to be designed to be multifunctional to induce a deep HOMO level and chain planarity (for interchain ordering) as well as good solution processability. (c) 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 854-862
Chemoselective Rhodium-Catalyzed Borylation of Bromoiodoarenes Under Mild Conditions
作者:Anthony J. Varni、Michael V. Bautista、Kevin J.T. Noonan
DOI:10.1021/acs.joc.0c00178
日期:2020.5.15
developed for the preparation of aryl boronate esters. The reaction proceeds undermildconditions with excellent selectivity for C-I bonds in bromoiodoarenes and exhibits broad functional group tolerance. This procedure can act as a complementary approach toward bifunctional arenes along with other metal-catalyzed borylations. Additionally, the reaction's utility in the preparation of monomers for metal-catalyzed