Contact printing of colloidal nanocrystal thin films for hybrid organic/quantum dot optoelectronic devices

Novel thin film optoelectronic devices containing both inorganic colloidal semiconductor quantum dots (QDs) and organic semiconductor thin films have been widely investigated in recent years for a variety of applications. Here, we review one of the most versatile and successful methods developed to integrate these two dissimilar material classes into a functional multilayered device: contact printing of colloidal QD films. Experimental details regarding the contact printing process are outlined, and the key advantages of this QD deposition method over other commonly encountered techniques are discussed. The use of tapping mode atomic force microscopy (AFM) to effectively characterize QD film morphology both on an elastomeric stamp (before contact printing) and as-transferred to the organic semiconductor receiving film (after contact printing) is also described. Finally, we offer suggestions for future efforts directed toward the goal of rapid, continuous QD deposition over larger substrates for the advancement of hybrid optoelectronic thin film devices

Direct arylation polycondensation for synthesis of optoelectronic materials

Direct arylation polycondensation has been investigated to develop efficient methods for the preparation of conjugated polymeric materials for use in optoelectronic applications. The reaction conditions have been examined to achieve high molecular weights and minimal structural defects in the recurring structures. Under optimal conditions, the direct arylation method has several advantages over conventional methods, e.g., it has fewer synthetic steps and yields a high-molecular-weight and high-purity polymer. The high-quality polymeric materials that were obtained exhibited superior performance to those obtained using a conventional method when used in optoelectronic devices such as organic photovoltaics and field-effect transistors. Recent developments in C–H/C–H coupling polycondensation are also described