Innovative hybrid inorganic/organic structures (HIOS) should implement exciton creation by electrical injection in inorganic semiconductors followed by resonant energy transfer and light emission from the organic semiconductor. An inherent obstacle of such designs is the typically unfavorable energy level alignment at HIOS interfaces, which assists in exciton separation thus quenching light emission. Here, we introduce a technologically relevant method to optimize the hybrid structure's energy levels: ZnO and a tailored ladder-type oligophenylene. Using an organometallic donor interlayer the ZnO work function is substantially lowered eliminating the ZnO - L4P-sp3 interfacial energy level offsets enhancing the hybrid structure's radiative emission yield sevenfold.
This work is part of a research project aimed at realising conducting polymer matrices for interfacing with cultured neurons. The polymer matrix has a dual function, one as a medium for recording electrical activity; the other is chemical stimulation through the release of bioactive molecules. In this work we use poly-3-hexylthiophene as a conducting polymer matrix. To test the polymer’s ability to release molecules upon the application of a potential it was doped with glutamate (GA). GA is an important neurotransmitter, and its controlled release can be important in several medical and tissue engineering applications. Diffusional and controlled release of GA from the polymer were assessed. Biocompatibility of the samples was evaluated at each stage using neuroblastoma cell cultures.