- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Bulk-heterojunction polymer photovoltaic cells manufactured using non-halogenated and non-aromatic solvent
摘要： The use of photovoltaic devices as converters of solar energy into electricity is a relevant technology to the global energy needs and, at the same time, it mitigates the negative impact on the environment caused by conventional sources. Although polymer solar cells are properly considered as clean and renewable source of electricity production, the processing involved in the manufacture of such devices still contains toxic elements. The formation of thin films of active layer in bulk-heterojunction organic solar cells, as example, usually uses halogenated solvents as chlorobenzene (CB), dichlorobenzene (DCB), or chloroform (CF), which represent certain risks of toxicity to the human body and to the environment. This work aims to show that it is possible to manufacture organic solar cells using less-toxic solvents, in special to the environment, whose final efficiency results are similar to those that have been processed by conventional halogenated solvents. With the aid of the Hansen solubility parameters (HSP), we identified non-halogenated and non-aromatic solvent that showed chemical compatibility with donor polymers and acceptor molecules used in the device’s active layer. The fabricated devices were then characterized and their photovoltaic responses compared to the conventional equivalents.
关键词： non-halogenated solvents,polymer solar cells,photovoltaic devices,non-aromatic solvents,solar energy,halogenated solvents,Hansen solubility parameters
更新于2025-09-23 15:21:01
-
Effects of non-halogenated solvent on the main properties of a solution-processed polymeric thin film for photovoltaic applications: a computational study
摘要： Organic photovoltaic (OPV) devices reached high solar conversion efficiencies but they are usually processed using halogenated toxic solvents. Hence, before OPV devices can be mass-produced by industrial processing, it would be desirable to replace those solvents with eco-friendly ones. Theoretical tools may be then a powerful ally in the search for those new solvents. In order to better understand the mechanisms behind the interaction between solvent and polymer, classical molecular dynamics (MD) calculations was used to produce a thin film of poly(4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b’]dithiophene-2,6-diyl3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl (PTB7-Th), processed using two different solvents. The PTB7-Th is widely applied as a donor material in OPVs. The first solvent is the ortho-dichlorobenzene (o-DCB), which is a highly toxic solvent widely used in lab-scale studies. The second solvent is the ortho-methylanisole (o-MA), which is an eco-friendly solvent for organic photovoltaic (OPV) manufacturing. Here we use a solvent evaporation protocol to simulate the formation of the PTB7-Th film. We demonstrate that our theoretical MD calculations were able to capture some differences in macroscopic properties of thin films formed by o-DCB or o-MA evaporation. We found that the interaction of the halogenated solvent with the polymer tends to break the bonds between the lateral thiophenediyl groups and the main chain. We show that those defects may create traps that can affect the charge transport and also can be responsible for a blue shift in the absorption spectrum. Using the Monte Carlo method, we also verified the influence of the resulting MD morphology on the mobility of holes. Our theoretical results showed a good agreement with the experimental measurements and both demonstrate that o-MA can be used to make polymer thin films without any loss of key properties for the device performance. The findings here highlights the importance of theoretical results as a guide to the morphological optimization of green processed polymeric films.
关键词： Solvent evaporation,PTB7-Th,Molecular dynamics,Organic photovoltaic,Halogenated solvents,Eco-friendly solvents,Hole mobility
更新于2025-09-23 15:19:57