Polymer: Fullerene Bimolecular Crystals for Near-Infrared Spectroscopic Photodetectors

Polymer: Fullerene Bimolecular Crystals for Near-Infrared Spectroscopic Photodetectors

Scientific Highlights Sustainable energy conversion & storage systems 30 July 2017 2253 hits jags

Z. Tang, Z. Ma, A. Sánchez-Díaz, S. Ullbrich, Y. Liu, B. Siegmund, A. Mischok, K. Leo, M. Campoy-Quiles, W. Li, K. Vandewal, Adv. Mater. 2017, 1702184. DOI: https://doi.org/10.1002/adma.201702184

Spectroscopic photodetection is a powerful tool in disciplines such as medical diagnosis, industrial process monitoring, or agriculture. However, its application in novel fields, including wearable and biointegrated electronics, is hampered by the use of bulky dispersive optics. Here, solution-processed organic donor–acceptor blends are employed in a resonant optical cavity device architecture for wavelength-tunable photodetection. While conventional photodetectors respond to above-gap excitation, the cavity device exploits weak subgap absorption of intermolecular charge-transfer states of the intercalating poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene] (PBTTT):[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) bimolecular crystal. This enables a highly wavelength selective, near-infrared photoresponse with a spectral resolution down to 14 nm, as well as dark currents and detectivities comparable with commercial inorganic photodetectors. Based on this concept, a miniaturized spectrophotometer, comprising an array of narrowband cavity photodetectors, is fabricated by using a blade-coated PBTTT:PCBM thin film with a thickness gradient. As an application example, a measurement of the transmittance spectrum of water by this device is demonstrated.

See more posts on ICMAB related to: Sustainable energy conversion & storage systems

Related Topics: Sustainable energy conversion & storage systems

Also on ICMAB...


Your experience on this site will be improved by allowing cookies Cookie Settings