A step towards the electrophotonic nose: integrating 1D photonic crystals with organic light‐emitting diodes and photodetectors

An innovative integrated sensing platform for the detection of various chemical analytes via translating the photonic stop-band shift of a one-dimensional photonic crystal (PC) into an electrical current change is proposed. The miniaturized sensing platform features an organic light-emitting diode (OLED) as a light source and an organic photodetector (OPD) as a light sensor and allows for the detection of ethanol vapor concentrations down to approximate to 10 parts per million (ppm) in nitrogen, which corresponds to a stop-band shift of approximate to 27 pm. The resolution of the proposed platformexceeds the capabilities of most commercial spectrometers and by far the human eye, while, at the same time, such a sensor is less expensive and less power consuming than a spectrometer. The presented setup is generic and can detect optical changes in the transmission of PCs, which can be induced by both vapor adsorption or by a liquid analyte, as demonstrated with a microfluidic setup.