Abstracts Book - IMRC 2018

• SC4-P017
A FLUORENE-DIKETOPYRROLOPYRROLE POLYMER PREPARED BY
DIRECT ARYLATION POLYMERIZATION FOR ORGANIC SOLAR
CELLS
Alejandra Montoya del Angel 1 , Patricia García Ramírez 1 , Jonatan Rodriguez Rea 1 , Marisol
Güizado Rodríguez 1 , Victor Barba 2 , Jose-Luis Maldonado 3
1
Universidad Autónoma del Estado de Morelos, Centro de Investigación en Ingeniería y
Ciencias Aplicadas, Mexico. 2 Universidad Autónoma del Estado de Morelos, Centro de
Investigaciones Químicas, Mexico. 3 Centro de Investigaciones en Optica, Grupo de Propiedades
Ópticas de la Materia, Mexico.
Organic solar cells (OSCs) are a promising and renewable energy source, of low
cost and easy manufacture. Active layer of solar cells under the bulk
heterojunction architecture (BHJ), is currently the most used configuration
having a better PV performance with the increase of interfacial area so that there
is greater contact between the donor material and the acceptor one
[1]. Conjugated polymers with Donor-Acceptor (D-A) units are alternatively
linked with an intramolecular charge transfer between both units leading to low
band gap [2]. Recently, direct arylation polymerization (DAr) has been applied as
an alternative method to synthesize a variety of conjugated polymers with
advantages of polymerization in fewer synthetic steps, better atom economy
and it less toxic in comparison to the traditional transition metal catalyzed
polymerization methods (Stille, Suzuki) [3]. Diketopyrrolopyrrole (DPP) acceptor
unit shows strong absorption towards the infrared, it favors a quinoid structure
and leads to high mobility values [4]. Fluorene offers a number of advantages,
the most significant being its ability to impart solubility while maintaining a high
degree of delocalization [5]. In this work, a polymer based on 2,2´-(9,9-dioctyl-
9H-fluorene-2,7-diyl)bisthiophene and 3,6-bis(5-bromo-2-thienyl)-2,5-bis(2-
hexyldecyl)-2,5-dihydro-pyrrolo[3,4-c]pyrrole-1,4-dione was synthetized by
direct arylation polymerization. Subsequently, D-A polymer was analyzed by 1 H
NMR, DSC, TGA, GPC, FT-IR, UV-vis; for instance, Mn = 6.3 KD and PDI = 1.6,
absorption bands at 410 and 655 nm, decomposition temperature Td = 445.5 o C,
frontier energy levels: HOMO = -5.84 eV and LUMO = -3.66 eV, and a band gap =
2.18 eV. Evaluation in organic solar cells by using the BHJ architecture with
ITO/PEDOT: PSS/copolymer: PC71BM/PFN/FM configuration was carried out.
Devices were manufactured by the spin coating method, showing a Jsc = 3.02
mA/cm 2 , Voc = 0.72 V, FF = 0.41 and PCEmax = 0.91 %.