Fuel Cells: Structure‐Morphology‐Property Relationships of Non‐Perfluorinated Proton‐Conducting Membranes (Adv. Mater. 42/2010)

A fundamental understanding of structure‐morphology‐property relationships of proton exchange membranes (PEMs) is crucial in order to improve the cost, performance, and durability of PEM fuel cells (PEMFCs). In this context, there has been an explosion over the past five years in the volume of research carried out in the area of non‐perfluorinated, proton‐conducting polymer membranes, with a particular emphasis on exploiting phase behavior associated with block and graft copolymers. This progress report highlights a selection of interesting studies in the area that have appeared since 2005, which illustrate the effects of factors such as acid and water contents and morphology upon proton conduction. It concludes with an outlook on future directions.     

Inside Front Cover: Polarized‐Light‐Emitting Quantum‐Rod Diodes (Adv. Mater. 11/2005)

Polarized‐light‐emitting quantum‐rod diodes have been successfully produced using thin layers of quantum rods oriented by a rubbing technique, as shown on the inside cover. Hikmet and co‐workers report on p. 1436 that diode emission at 620 nm with a luminance efficiency of 0.65 cd A^–1 and an external quantum efficiency of 0.49 % is obtained. Light emitted polarized parallel to the long axis of the rods is 1.5 times more intense than that polarized perpendicular to the rods.