| 초록 |
The long-term stabilities of polymer solar cells (PSCs) are key requirements for commercialization, but progress has been limited in this area. Most PSCs are not stable as subsequent exposure to heat which drives further macrophase separation at the micrometer scale and environmental stress that causes the mechanical failure at the weak interfaces of the PSCs. Here, we present various molecular designs of electroactive polymers to improve the thermal stability of PSCs. For example, we developed a series of well-defined poly(3-hexylthiophene)-graft-poly(2-vinylpyridine) (P3HT-g-P2VP) copolymers, in which the P2VP chains had different molecular weights. P3HT-g-P2VP polymers can be used as efficient compatibilizers in the active layer of PSCs and can modify the sharp interface between polymer donors and fullerenes, resulting in a dramatic enhancement of thermal stabilities and the mechanical properties of PSCs. In the second part of talk, a template approach is presented for the fabrication of semiconducting polymer blend thin films that combine the properties of electrical conductivity and enhanced stability. Nanometer-sized monodisperse polystyrene nanospheres (PS NSs) were designed as an opal template for the formation of three-dimensionally continuous PEDOT:PSS films. The resultant films were successfully applied as an anode buffer layer to produce highly-efficient PSCs with improved ambient stability. Furthermore, the PS NSs can be used as interfacial modifiers and binders in the PEDOT:PSS film, which resulted in the enhancement of mechanical durability of the PSCs. |
