Dissipative Particle Dynamics Simulation Of The Mesoscopic Morphology Of Bulk Heterojunction Organic Photoyoltaic Cells

In a era with increasing population and natural resources being depleted, solar cell has appeared to be a perfect solution to solve the crisis. Now the most cells being used are those based on Si which cost a lot and are difficult to prepare. In recent years, organic polymer photovoltaic cells have shown advantages to be widely used in the future to replace the inorganic solar cells. This kind of solar cells is relatively simply to prepare, costs much less than inorganic solar cells and is much more flexible. Among organic polymer photovoltaic cells, bulk heterojunction organic photovoltaic cells perform better than the rest.Computer simulation has been proven to a useful tool and has been widely used by chemists throught this discipline. Experimental observations have been understood more deeply and more reaction mechanisms have been clarified though computer simulation. Computer simulations also guide the experimental conduction. Dissipative Particle Dynamics is essentially a coarse-grained method using soft potential which allows a large time step in the simulation and this method has been used to model polymers with large amount of atoms. In this thesis, we employ Dissipative Particle Dynamics to simulation the light sensitive layer of two different kinds of organic polymer solar cells for different weight ratio under annealing. On the basis of the theoretical background of this method, we build the coarse-grained model and by using the bonded potential coefficients and non-bonded potential coefficients we characterize the system through contacting area, specific surface area, radial density function, order parameter, ratio of crystallinity which are quantities that are hard to get by using experimental conductions.