Organic multilayer photoconductor utilizing a spacer layer

Abstract

Chemosensors hold many vital applications in today's world, particularly as detectors for explosives. There is still vast room for improvement as other technologies-particularly those of explosives-continue to evolve and expand. Herein, we develop a novel device structure with the potential for much higher sensitivity. The lateral bilayer photoconductor is comprised of an exciton generation layer (EGL) and a charge transport layer (CTL). This separates the functionality of chemical sensing from the charge transport, allowing each film to be independently optimized. As a further improvement on this structure, we introduce a spacer layer to separate charge carriers in the EGL and the CTL, reducing bimolecular recombination at the interface. As a proof of concept, we fabricate and characterize lateral multilayer photoconductors composed of small molecule organic films. It is experimentally demonstrated that the utilization of a spacer layer can produce an order of magnitude enhancement in quantum efficiency over the of a spacer layer can produce an order of magnitude enhancement in quantum efficiency over the The work reported here provides encouraging results in the fields of chemosensors and organic optoelectronics.