scholarly journals Emphasizing the Operational Role of a Novel Graphene-Based Ink into High Performance Ternary Organic Solar Cells

Author(s):  
Minas M. Stylianakis ◽  
Dimitriοs M. Kosmidis ◽  
Katerina Anagnostou ◽  
Christos Polyzoidis ◽  
Miron Krassas ◽  
...  

A novel solution-processed graphene-based material was synthesized by treating graphene oxide (GO) with 2,5,7-trinitro-9-oxo-fluorenone-4-carboxylic acid (TNF-COOH) moieties, via simple synthetic routes. The yielded molecule N-[(carbamoyl-GO)ethyl]-N’-[(carbamoyl)-(2,5,7-trinitro-9-oxo-fluorene)] (GO-TNF) was thoroughly characterized and it was shown that it presents favorable highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels to function as a bridge component between the polymeric donor poly({4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl] thieno[3,4-b]thiophenediyl}) (PTB7) and the fullerene derivative acceptor [6,6]-phenyl-C71-butyric-acid-methylester (PC71BM). In this context, a GO-TNF based ink was prepared and directly incorporated within the binary photoactive layer, in different volume ratios (1-3% ratio to the blend), for the effective realization of inverted ternary organic solar cells (OSCs) of the structure ITO/PFN/PTB7:GO-TNF:PC71BM/MoO3/Al. The addition of 2% v/v GO-TNF ink led to a champion power conversion efficiency (PCE) of 8.71% that was enhanced by ~13% as compared to the reference cell.

Nanomaterials ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 89 ◽  
Author(s):  
Minas M. Stylianakis ◽  
Dimitrios M. Kosmidis ◽  
Katerina Anagnostou ◽  
Christos Polyzoidis ◽  
Miron Krassas ◽  
...  

A novel solution-processed, graphene-based material was synthesized by treating graphene oxide (GO) with 2,5,7-trinitro-9-oxo-fluorenone-4-carboxylic acid (TNF-COOH) moieties, via simple synthetic routes. The yielded molecule N-[(carbamoyl-GO)ethyl]-N′-[(carbamoyl)-(2,5,7-trinitro-9-oxo-fluorene)] (GO-TNF) was thoroughly characterized and it was shown that it presents favorable highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels to function as a bridge component between the polymeric donor poly({4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl] thieno[3,4-b]thiophenediyl}) (PTB7) and the fullerene derivative acceptor [6,6]-phenyl-C71-butyric-acid-methylester (PC71BM). In this context, a GO-TNF based ink was prepared and directly incorporated within the binary photoactive layer, in different volume ratios (1%–3% ratio to the blend) for the effective realization of inverted ternary organic solar cells (OSCs) of the structure ITO/PFN/PTB7:GO-TNF:PC71BM/MoO3/Al. The addition of 2% v/v GO-TNF ink led to a champion power conversion efficiency (PCE) of 8.71% that was enhanced by ~13% as compared to the reference cell.


2021 ◽  
Vol 11 (2) ◽  
pp. 646
Author(s):  
Shabaz Alam ◽  
M. Shaheer Akhtar ◽  
Abdullah ◽  
Eun-Bi Kim ◽  
Hyung-Shik Shin ◽  
...  

In order to develop new and effective donor materials, a planar donor-π-acceptor (D-π-A) type small organic molecule (SOM), 2-(4-fluorobenzoyl)-3-(5″-hexyl-[2,2′:5′,2″-terthiophen]-5-yl) acrylonitrile, named as H3T-4-FOP, was synthesized by the reaction of 4-fluorobenzoylacetonitrile (as acceptor unit) and hexyl terthiophene (as donor unit) derivatives. Promising optical, solubility, electronic and photovoltaic properties were observed for the H3T-4-FOP SOM. Significantly, the presence of 4-fluorobenzoylacetonitrile as an acceptor unit in H3T-4-FOP SOM tuned the optical band gap to ~2.01 eV and procured the reasonable energy levels as highest occupied molecular orbital (HOMO) of −5.27 eV and lowest unoccupied molecular orbital (LUMO) −3.26 eV. The synthesized H3T-4-FOP SOM was applied as a donor material to fabricate solution-processed bulk heterojunction organic solar cells (BHJ-OSCs) with an active layer of H3T-4-FOP: PC61BM (1:2, w/w) and was validated as having a good power conversion efficiency (PCE) of ~4.38%. Our studies clearly inspire for future designing of multifunctional groups containing the 4-fluorobenzoylacetonitrile based SOM for high performance BHJ-OSCs.


2021 ◽  
Vol 25 ◽  
Author(s):  
Fabiana Pandolfi ◽  
Martina Bortolami ◽  
Marta Feroci ◽  
Leonardo Mattiello ◽  
Vincenzo Scarano ◽  
...  

: Thiophene derivatives, either "small molecules," oligomers or polymers, play a role of primary importance among organic semiconductors. Therefore they have numerous and different technological applications in the field of Organic Electronics. For this reason, thiophene-based materials are found in devices such as organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs), organic solar cells (OSCs), organic photodetectors, and many others. Oligothiophenes and polythiophenes have in common excellent charge transport properties and synthetic procedures that are now well established. Furthermore, oligothiophenes do not possess the intrinsic disadvantages of polythiophenes, such as the lack of well-defined structures and the inevitable presence of impurities. Electrochemistry can give a significant contribution to the field of oligothiophenes not only by allowing the determination of the highest-occupied molecular orbital (HOMO) and the lowest-unoccupied molecular orbital (LUMO) energy levels by the means of cyclic voltammetry (CV), but also rendering oligothiophenes syntheses more expeditious in comparison with the classical organic ones. This review outlines the application of electrochemistry techniques to the synthesis of oligothiophene derivatives.


2017 ◽  
Vol 5 (32) ◽  
pp. 16702-16711 ◽  
Author(s):  
Jisoo Shin ◽  
Min Kim ◽  
Boseok Kang ◽  
Jaewon Lee ◽  
Heung Gyu Kim ◽  
...  

The control of the molecular energy levels of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) is crucial to the design of highly efficient polymer solar cells (PSCs).


Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4100 ◽  
Author(s):  
Hugo Gaspar ◽  
Flávio Figueira ◽  
Karol Strutyński ◽  
Manuel Melle-Franco ◽  
Dzmitry Ivanou ◽  
...  

Novel C60 and C70 N-methyl-fulleropyrrolidine derivatives, containing both electron withdrawing and electron donating substituent groups, were synthesized by the well-known Prato reaction. The corresponding highest occupied molecular orbital (HOMO)/lowest unoccupied molecular orbital (LUMO) energy levels were determined by cyclic voltammetry, from the onset oxidation and reduction potentials, respectively. Some of the novel fullerenes have higher LUMO levels than the standards PC61BM and PC71BM. When tested in PffBT4T-2OD based polymer solar cells, with the standard architecture ITO/PEDOT:PSS/Active-Layer/Ca/Al, these fullerenes do not bring about any efficiency improvements compared to the standard PC71BM system, however they show how the electronic nature of the different substituents strongly affects the efficiency of the corresponding organic photovoltaic (OPV) devices. The functionalization of C70 yields a mixture of regioisomers and density functional theory (DFT) calculations show that these have systematically different electronic properties. This electronic inhomogeneity is likely responsible for the lower performance observed in devices containing C70 derivatives. These results help to understand how new fullerene acceptors can affect the performance of OPV devices.


2017 ◽  
Vol 73 (6) ◽  
pp. 458-463
Author(s):  
Yan-Xiao Su ◽  
Chao-Zhi Zhang ◽  
Ming-Xia Song

Electron-donating molecules play an important role in the development of organic solar cells. (Z)-2-(2-Phenylhydrazinylidene)acenaphthen-1(2H)-one (PDAK), C18H12N2O, was synthesized by a Schiff base reaction. The crystal structure shows that the molecules are planar and are linked together forming `face-to-face' assemblies held together by intermolecular C—H...O, π–π and C—H...π interactions. PDAK exhibits a broadband UV–Vis absorption (200–648 nm) and a low HOMO–LUMO energy gap (1.91 eV; HOMO is the highest occupied molecular orbital and LUMO is the lowest unoccupied molecular orbital), while fluorescence quenching experiments provide evidence for electron transfer from the excited state of PDAK to C60. This suggests that the title molecule may be a suitable donor for use in organic solar cells.


2015 ◽  
Vol 3 (1) ◽  
Author(s):  
V. V. Malov ◽  
A. R. Tameev ◽  
S. V. Novikov ◽  
M. V. Khenkin ◽  
A. G. Kazanskii ◽  
...  

AbstractOptical and photoelectric properties of modern photosensitive polymers are of great interest due to their prospects for photovoltaic applications. In particular, an investigation of absorption and photoconductivity edge of these materials could provide valuable information. For these purpose we applied the constant photocurrent method which has proved its efficiency for inorganic materials. PCDTBT and PTB7 polymers were used as objects for the study as well as their blends with a fullerene derivative PC71BM. The measurements by constant photocurrent method (CPM) show that formation of bulk heterojunction (BHJ) in the blends increases photoconductivity and results in a redshift of the photocurrent edge in the doped polymers compared with that in the neat polymers. Obtained from CPM data, spectral dependences of absorption coefficient were approximated using Gaussian distribution of density-of-states within HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) bands. The approximation procedure allowed us to evaluate rather optical than electrical bandgaps for the studied materials. Moreover, spectra of polymer:PC71BM blends were fitted well by the sum of two Gaussian peaks which reveal both the transitions within the polymer and the transitions involving charge transfer states at the donor-acceptor interface in the BHJ.


2021 ◽  
Vol 01 ◽  
Author(s):  
Min Deng ◽  
Zhenkai Ji ◽  
Xiaopeng Xu ◽  
Liyang Yu ◽  
Qiang Peng

Background: Perylene diimide (PDI) is among the most investigated non-fullerene electron acceptor for organic solar cells (OSCs). Constructing PDI derivatives into three-dimensional propeller-like molecular structures is not only one of the viable routes to suppress the over aggregation tendency of the PDI chromophores, but also raises possibilities to tune and optimize the optoelectronic property of the molecules. Objective: In this work, we reported the design, synthesis, and characterization of three electron-accepting materials, namely BOZ-PDI, BTZ-PDI, and BIZ-PDI, each with three PDI arms linked to benzotrioxazole, benzotrithiazole, and benzotriimidazole based center cores, respectively. Method: The introduction of electron-withdrawing center cores with heteroatoms does not significantly complicate the synthesis of the acceptor molecules but drastically influences the energy levels of the propeller-like PDI derivatives. Result: The highest power conversion efficiency was obtained with benzoxazole-based BOZ-PDI reaching 7.70% for its higher photon absorption and charge transport ability. Conclusion: This work explores the utilization of electron-withdrawing cores with heteroatoms in the propeller-like PDI derivatives, which provides a handy tool to construct high-performance non-fullerene acceptor materials.


Sign in / Sign up

Export Citation Format

Share Document