Cyanine dyes have near infrared absorption. For instance, indocyanine green (ICG) is a cyanine dye with maximum absorption around 800 nm and is used as a diagnostic agent. In addition, various derivatives of ICG are being investigated as low toxicity, minimal invasive, and bio-imaging dyes. Alternatively, O0574 is a compound containing a carboxy group on the polymethine moiety of ICG. It is expected to be used as a material with characteristics that are close to but different from ICG, such as solubility and specific reactivity with biomolecules. TCI also offers C3693, a cyanine dye whose maximum absorption wavelength and maximum fluorescence wavelength are reported at 748 and 779 nm, respectively.
High-Regioregular P3HT-Based Transistor Realizing Hole Mobility of Over 20 cm2/Vs
High-performance OFETs using imidazole-type ionic liquids (ILs) as gate dielectrics in polymer semiconductor P3HT [P2513]-based OFETs have been reported. The IL-gated OFETs achieved carrier densities of the order of 1016 cm-2. In particular, the DMIM-BF4 [D5373] gated high-regioregular P3HT-based device showed a carrier mobility of 20.2 cm2/Vs, which is the highest performance observed in a P3HT-based OFET to date. Moreover, the IL-gated OFETs possess an operation stability of over 40 days under ambient condition, so they can be expected as candidates for commercial products such as high-sensitivity biosensors.
Building Blocks for Organic Semiconducting Non-Fullerene Acceptor Materials
2-(3-Oxoinden-1-ylidene)propanedinitrile type building blocks, D2054, D5945 and D5815 are commonly used for non-fullurene acceptor (NFA) materials. The properties of NFA materials can be tuned by the containing atoms of these building blocks. It has been reported that NFA materials synthesized from these building blocks enable a high-performance organic solar cell with over 15% of PCE.
Useful Acceptor-Type Organic Semiconductor Building Blocks
Naphtho[1,2-c:5,6-c']bis([1,2,5]thiadiazole) (NTz) structures, N1105, D5288 and B5470 are useful electron-deficient type building blocks for organic semiconductors. Some donor-acceptor conjugated polymers containing the NTz structures exhibited better power conversion efficiency (PCE) compared with widely used 2,1,3-benzothiadiazole-based polymers in organic photovoltaic devices. In addition, several conjugated polymers exhibiting beyond 10% PCEs were reported in 2016.