Relationship between photostability and nanostructures in DTS(FBTTh2)2:fullerene bulk-heterojunction films

Yamane, Satoshi; Suzuki, Yasuyuki; Miyadera, Tetsuhiko; Koganezawa, Tomoyuki; Arai, Koji; Akiyama, Yuki; Chikamatsu, Masayuki; Yoshida, Yūji; Suda, Hiroyuki; Mizukado, Junji

doi:10.1016/j.solmat.2016.02.011

Cited by 8 publications

(4 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Decrease in absorption intensity indicates that degradation is taking place. 13,14,17,18,[27][28][29] Iyer and coworkers 17,18 reported that CH-π and π-π interactions between CPs and carbon nanomaterials could be the main reason behind the increased photostability of their composite. In sum, the photostability of our PCDTBT: PCBM suspensions improves significantly (∼35%) through GNPs addition.…”

Section: Resultsmentioning

confidence: 99%

“…Previous results suggested that the decrease in absorption intensity indicates a photooxidation at the π-conjugate moieties. 28,29 McGehee, 29 Ran 27 and their coworkers, studied the photo-oxidation mechanism of CPs and demonstrated, from the thermodynamic point of view, the ability of these CPs to donate photogenerated charges to oxygen. On the other hand, di-atomic oxygen, O 2 , tends to form the superoxide anion, O , 2 •due to the transfer of the photogenerated electron (Fig.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Hybrid PCDTBT:PCBM:Graphene-Nanoplatelet Photoabsorbers

Mohammadnezhad¹,

Aïssa²,

Harnagea³

et al. 2020

J. Electrochem. Soc.

View full text Add to dashboard Cite

We study the photoactive properties of poly [N-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT): [6,6]-Phenyl-C71-butyric acid methyl ester (PCBM) thin films under ultraviolet irradiation as well as their photo-oxidation, thermal and electrical properties. We compare their stability and performance with composites obtained by integrating graphene nanoplatelets (GNPs). Compared to the pristine polymer, an increase in light absorption and photoluminescence quenching were observed in PCDTBT:PCBM:GNPs. This indicates the occurrence of electron transfer from the conjugated polymer to the empty state of the GNP, through the interfacial bonding based on CH-π and ππ interactions, thereby reducing the photodegradation of the active layer. This is manifested by a significant decline in photo-oxidation, followed by improved thermal stability and suppressed phase separation and aggregation of the PCBM molecules. Atomic force microscopy imaging of the PCDTBT:PCBM:GNPs nanocomposite revealed that graphene flakes enhance the order of the polymeric structures. Finally, we discuss the effect of the GNPs content on the electrical conductivity and electron mobility of the photoactive layer. Our findings offer significant insights into the PV properties and photo physics of hybrid organic bulk-heterojunction solar cells, paving the way towards enhancing their durability and long term performance.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Hybrid PCDTBT:PCBM:Graphene-Nanoplatelet Photoabsorbers

Mohammadnezhad¹,

Aïssa²,

Harnagea³

et al. 2020

J. Electrochem. Soc.

View full text Add to dashboard Cite

show abstract

“…Fortunately, the increased molecular order has been found to successfully exclude oxygen from the domains and thus decrease the photooxidation rate in small molecules/fullerene blend system. 28 Usually, thermal annealing was employed to improve molecular order, in which the annealing time appeared to be important for controlling the content of the amorphous phase. Besides, some useful methods were also developed to improve molecular order and inhibit molecular diffusion, which can be universally applicable to various polymer donors, such as sequential deposition of donor and acceptor 25 and an upside-down drying method.…”

mentioning

confidence: 99%

“…Indeed, a light-induced disorder phase is one of the possible factors leading to device degradation, while the residual oxygen in the domains should act as the catalyst to accelerate this degradation process. Fortunately, the increased molecular order has been found to successfully exclude oxygen from the domains and thus decrease the photooxidation rate in small molecules/fullerene blend system . Usually, thermal annealing was employed to improve molecular order, in which the annealing time appeared to be important for controlling the content of the amorphous phase.…”

mentioning

confidence: 99%

Hierarchical Morphology Stability under Multiple Stresses in Organic Solar Cells

Zhou

Xin

2019

ACS Energy Lett.

View full text Add to dashboard Cite

Improving device stability is an imperative area of realizing commercial utilization for organic solar cells (OSCs). Morphology evolutions of solution-processable active layers have proved to be responsible for ubiquitous device degradation due to their profound impacts on charge generation, transport, and extraction. This Perspective aims to understand and promote device stability in terms of morphology control and evolution from the subnanoscale to hundreds of nanometers. We start with analyzing the role of molecular packing and aggregation within domains on device stability and then focus on the structure of phase separation stemming from donor-rich and acceptor-rich domains. Potential mechanisms of morphology evolution within the individual length scale and some related reinforcing strategies when suffering from heating, irradiation, and mechanical stress are discussed. Finally, we summarize and propose major limitations and future directions for further promoting research on device stability in OSCs.

show abstract

Low Boiling Point Solvent Additives for Improved Photooxidative Stability in Organic Photovoltaics

Holliday

Luscombe

2017

Adv Elect Materials

View full text Add to dashboard Cite

The efficiency of organic photovoltaic (OPV) cells is rapidly increasing. However, many of the highest performance OPV devices are also the most unstable, including the two widely used benzodithiophene‐co‐thieno[3,4‐b]thiophene polymers, PTB7 and PTB7‐Th. Here it is shown that both the choice of pendant side chain, and solvents used for film deposition, have an important effect on active layer stability. Specifically, polymers with alkylthienyl side chains are found to be less stable than polymers with alkoxy side chains. Secondly, high boiling point solvent additives such as 1,8‐diiodooctane are found to dramatically accelerate photooxidation unless they are removed fully during device processing, which may be attributed to increased oxygen diffusion in films containing residual solvent. Replacing these higher boiling point solvent additives with lower boiling additives can greatly enhance the polymer stability without requiring high vacuum treatment, making these systems more scalable and compatible with roll‐to‐roll printing. Based on this finding, the non‐halogenated solvent system o‐xylene with 2% N‐methylpyrrolidone is explored as a route to achieving higher active layer stability, while maintaining the favorable, intermixed morphology achieved with higher boiling point, halogenated solvent additives. This result offers a promising way forward in the development of scalable, stable, and high‐efficiency organic solar cells.

show abstract

Relationship between photostability and nanostructures in DTS(FBTTh2)2:fullerene bulk-heterojunction films

Cited by 8 publications

References 35 publications

Hybrid PCDTBT:PCBM:Graphene-Nanoplatelet Photoabsorbers

Hybrid PCDTBT:PCBM:Graphene-Nanoplatelet Photoabsorbers

Hierarchical Morphology Stability under Multiple Stresses in Organic Solar Cells

Low Boiling Point Solvent Additives for Improved Photooxidative Stability in Organic Photovoltaics

Contact Info

Product

Resources

About