Effect of chemical modifications on the electronic structure of poly(3‐hexylthiophene)

Oliveira, Eliezer Fernando; Camilo-Jr, Alexandre; Silva‐Filho, Luiz Carlos da; Lavarda, Francisco Carlos

doi:10.1002/polb.23274

Cited by 18 publications

(36 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This approach has been applied with satisfactory results in studies of conjugated polymers 8,9,16 , and is feasible owing to the size of the systems studied here, as well as the number of conformers analyzed. The exclusive use of ab-initio methods would result in considerable computational cost.…”

Section: Calculation Proceduresmentioning

confidence: 99%

“…The exclusive use of ab-initio methods would result in considerable computational cost. We adopted fully coplanar polymeric structures, as expected in the solid state 1,10,14,16 , and the alkyl branches were initially predisposed in an antiperiplanar conformation, as we had predicted in previous studies to be the most likely 8,9 . All studied structures were optimized by the HartreeFock semiempirical Parametric Method 6 (PM6) 26 implemented in the computational package MDPAC2012 27 .…”

Section: Calculation Proceduresmentioning

confidence: 99%

“…All studied structures were optimized by the HartreeFock semiempirical Parametric Method 6 (PM6) 26 implemented in the computational package MDPAC2012 27 . We chose PM6 because of its satisfactory performance in studies with polythiophene derivatives 8,9,16,28,29 . The geometry optimization process was considered completed when the gradient norm drops below 0.01 kcal.mol -1 /Å.…”

Section: Calculation Proceduresmentioning

confidence: 99%

“…Molecular modeling of conjugated polymers has been a challenge for the scientific community for several reasons, for example, the fact that they are large molecules and thus easily deformable and the presence of side chains 2 . Several theoretical studies of these materials have been conducted based on quantum or classical mechanics [8][9][10][11][12][13] , but the number of variables that must be taken into account in any model carries a high computational cost 8 . Thus, it is necessary to find ways to reduce this cost to simulate these materials without compromising the quality of results.…”

Section: Introductionmentioning

confidence: 99%

“…We also tried to discover whether there might be a characteristic length of the side chains at which the electronic properties would remain unchanged; this might be suitable for use as a modeling approach. We chose to study poly(3-hexylthiophene) (P3HT), a polymer widely used in organic devices (Figure 1) [8][9][10][20][21][22][23][24] . This polymer has a hexyl side chain in each monomer unit.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Effect of the length of alkyl side chains in the electronic structure of conjugated polymers

Oliveira

Lavarda

2014

Mat. Res.

Self Cite

View full text Add to dashboard Cite

Computational modeling studies of conjugated polymers have been shown to present many challenges. Dne such challenge is to find ways to reduce the computational cost for these studies without compromising the quality of the results. An approach longly used in the literature for this purpose is replacing long alkyl side chains (with six or more carbons) with a methyl group. This work reports on a theoretical study conducted with the conjugated polymer poly(3-hexylthiophene), which contains a hexyl side chain attached to the monomer, to verify the influence of the size of the alkyl side chain on its electronic structure. The results indicated that, for polymers containing long alkyl side chains, replacement with a propyl group offered full saturation of all properties under review, showing it to be a good approach.

show abstract

Section: Calculation Proceduresmentioning

confidence: 99%

Section: Calculation Proceduresmentioning

confidence: 99%

Section: Calculation Proceduresmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Effect of the length of alkyl side chains in the electronic structure of conjugated polymers

Oliveira

Lavarda

2014

Mat. Res.

Self Cite

View full text Add to dashboard Cite

show abstract

Dithieno[2,3‐d:2′,3′‐d′]naphtho[2,1‐b:3,4‐b′]dithiophene based medium bandgap conjugated polymers for photovoltaic applications

Yang

et al. 2016

J of Applied Polymer Sci

View full text Add to dashboard Cite

Three novel medium band gap (MBG) conjugated polymers (CPs) (named as P1, P2, and P3, respectively) were developed by copolymerizing 2,7-dibromo-10,11-di(2-hexyldecyloxy)dithieno[2,3-d:2 0 ,3 0 -d 0 ]naphtho[2,1-b:3,4-b 0 ]dithiophene (NDT-Br) with three different units: 2,5-bis(tributylstannyl)thiophene, 2,5-bis(trimethylstannyl)thieno[3,2-b]thiophene and trans21,2-bis(tributylstannyl)ethene, respectively. The thermal, optical, and electrochemical properties of the polymers were investigated. All of the polymers have good thermal stability and medium band gap ( 1.9 eV). Prototype bulk heterojunction photovoltaic cells based on the blend P1/P2/P3 and [6,6] phenyl-C61 butyric acid methyl ester (PC 61 BM) were assembled and the photovoltaic properties were assessed. Power conversion efficiencies (PCEs) of 1.61% 2.43% have been obtained under 100 mW cm 22 illumination (AM1.5).

show abstract

Copolymers with similar comonomers: Tuning frontier orbital energies for application in organic solar cells

Oliveira

Lavarda

2016

Polymer Engineering & Sci

Self Cite

View full text Add to dashboard Cite

Today, there is an intense search for new electron donor polymers for the active layers of organic solar cells. The synthesis of copolymers, in which there is a mix of electron donor monomers with others that are electron acceptors, is a currently employed approach that is used to obtain new polymers with more interesting electronic properties. Usually, the comonomers have a very different structure and the energies of the frontier electronic levels are unpredictable. We demonstrate in this work that the approach of using similar comonomers allows for the provision of copolymers with predictable energies of the frontier electronic levels. We explore the properties of copolymers consisting of monomers of poly(3-hexylthiophene), poly(3-hexyloxythiophene) and some poly(3-hexylthiophene) derivatives. The results indicate that the copolymers have intermediate frontier orbital energies when compared to the parent homopolymers and these energies are easy to predict. This approach is an alternative way of designing a copolymer with favorable tuning of the energies of the frontier electronic levels and is supported by experimental evidence. POLYM. ENG. SCI., 56:479-487, 2016. V C 2016 Society of Plastics Engineers INTRODUCTIONToday, there is a wide spectrum of important applications for organic conducting polymers (OCPs) in organic electronics [1][2][3][4][5]. Therefore, a control mechanism for the energies of the highest occupied and lowest unoccupied molecular orbitals (E HOMO and E LUMO ), the bandgap E LUMO -E HOMO (DE HL ) and optical properties is desirable in order to optimize the various types of devices [6,7]. These properties are crucial to the development of the promising technology of organic solar cells (OSC) [8,9].Currently, the scientific community has focused on two different ways of improving the efficiency of solar cells by controlling the electronic properties of OCPs [8][9][10]. The first adopted strategy has been to adjust the frontier electronic energy levels of the donor material to the levels of a given acceptor material. Normally, this is achieved through the design of OCPs with a lower E HOMO in order to increase the open-circuit voltage in the device (V OC ) [8][9][10][11][12][13]. The use of chemical substitutions is an effective way of implementing this change in the energies of the frontier orbitals, but with no major changes in the bandgap, as recently shown for poly(3-hexylthiophene) (P3HT) derivatives [14,15]. The second strategy is based on the design of new OCPs with a low bandgap in order to collect more photons of the solar spectrum and to increase the electric current in the device [8-10, 16, 17]. The donor-acceptor (DA) concept, which is the most frequently employed approach, is the synthesis of copolymers in which there is a mix of electron donor monomers with others that are electron acceptors [7,10]. Usually, the monomers have a very different structure and the resulting OCPs demonstrate a lower bandgap, but also a significant worsening in the other properties [18] as a decrease i...

show abstract

Effect of chemical modifications on the electronic structure of poly(3‐hexylthiophene)

Cited by 18 publications

References 37 publications

Effect of the length of alkyl side chains in the electronic structure of conjugated polymers

Effect of the length of alkyl side chains in the electronic structure of conjugated polymers

Dithieno[2,3‐d:2′,3′‐d′]naphtho[2,1‐b:3,4‐b′]dithiophene based medium bandgap conjugated polymers for photovoltaic applications

Copolymers with similar comonomers: Tuning frontier orbital energies for application in organic solar cells

Contact Info

Product

Resources

About