ABSTRACT
Recent developments in solution processable single junction polymer solar cells have led to a significant improvement in power conversion efficiencies from â¼5% to beyond 9%. While much of the initial efficiency improvements were driven through judicious design of donor polymers, it is the engineering of device architectures through the incorporation of inorganic nanostructures and better processing that has continued the efficiency gains. Inorganic nano-components such as carbon nanotubes, graphene and its derivatives, metal nanoparticles and metal oxides have played a central role in improving device performance and longevity beyond those achieved by conventional 3G polymer solar cells. The present work aims to summarise the diverse roles played by the nanosystems and features in state of the art next generation (4G) polymer solar cells. The challenges associated with the engineering of such devices for future deployment are also discussed.
Subject(s)
Polymers/chemistry , Solar Energy , Electrodes , Graphite/chemistry , Metal Nanoparticles/chemistry , Metals/chemistry , Nanotubes, Carbon/chemistry , Oxides/chemistry , Polystyrenes/chemistry , Thiophenes/chemistryABSTRACT
Recent studies on 2D substrates have revealed the importance of surface properties in affecting cell behaviour. In particular, surface topography appears to influence and direct cell migration. The development of new technologies of hot embossing and micro-imprinting has made it possible to study cell interactions with controlled micro features and to determine how these features can affect cell behaviour. Several studies have been carried out on the effect of microstructures on cell adhesion, cell guidance and cell proliferation. However, there is still a lack of knowledge on how these features affect mesenchymal stem cell differentiation. This study was designed to evaluate whether highly controlled microstructures on PMMA could induce rMSC differentiation into an osteogenic lineage. Structured PMMA was seeded with rMSC and cell number; cell morphology and cell differentiation were evaluated. Results confirm that microstructures not only affect cell proliferation and alignment but also have a synergistic effect with osteogenic medium on rMSC differentiation into mature osteoblasts.