Место издания:Enikolopov Institute of Synthetic Polymeric Materials of Russian Academy of Sciences Moscow
Первая страница:48
Последняя страница:48
Аннотация:One of the potential alternatives to crystalline silicon solar cells is plastic solar cells (PSC) made of thin films based on polymer materials, which can be easily applied layer by layer onto flexible substrates of a large area using wet processing methods. Such devices give such promising advantages as ease of producing, possible recyclability, and relatively low cost. For the widespread of PSC in daily practice, it is necessary to achieve many properties, such as high power conversion efficiency, durability, and stability with prolonged exposure to temperature changes. When developing PSC, many polymeric materials need to be tested. The use of computer simulations can significantly facilitate the process verification of the properties of various polymers before their using in real devices.This report discusses the problems of the design of computer models for investigations of the photoactive layer (PhL) of polymer solar cells. The PhL is a nanocomposite in which π-conjugated (semiconducting) polymers are used as matrices. Due to π-π stacking interactions, crystalline domains, which play an essential role in forming PhL properties, are formed in the structure of conjugated polymers. However, computer simulation methods have minimal possibilities for constructing models of polymeric materials, taking into account π-π interactions. This problem is especially acute for mesoscopic methods that allow the study of polymeric materials at relatively large lengths and time scales. We propose a method for taking into account π-π stacking interactions in mesoscale models and check it in the framework of the dissipative particle dynamics method. As a prototype of the polymer model, we use poly (3 -hexylthiophene). We show that taking into account π-π stacking interaction leads to self-assembly of the polymer chains into large stacks with strong alignment. These stacks form lamellae, which is in good agreement with the known experimental data. The proposed methodology could be helpful in studies of conjugated polymer materials, especially in the design of PSC and other photovoltaic devices.We also constructed the reverse-mapping procedure that makes it possible to create models of atomistic samples of PhL based on the final states of the mesoscopic models. This creates possibilities to construct the multiscale schemes for the simulation of the nanocomposites based on the conjugated polymers with various fillers to predict their thermophysical properties and thermal stability.