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Abstract: High‐performance n‐type thermoelectric polymers are vital in the development of polymer thermoelectric generators (PTEGs). However, the progress is very slow due to their low stability and low thermoelectric properties. Here, aniline oligomer‐block‐polyethylene glycol‐block‐aniline oligomer (ANI)n‐b‐PEO‐b‐(ANI)n) (n = 4, 8, 16) are prepared and studied. The results indicate that the (ANI)n‐b‐PEO‐b‐(ANI)n show unique temperature sensitivity and switch from p‐type to n‐type when the temperature is above 300 K. Differential scanning calorimetry curves show that the Tg of the (ANI)n‐b‐PEO‐b‐(ANI)n is lower than 300 K, indicating that PEO segments of the (ANI)n‐b‐PEO‐b‐(ANI)n easily move above 300 K and have high flexibility. Temperature‐dependent Raman spectra confirm that there are strong interactions between PEO segments and aniline oligomers during the raising temperature, and PEO chains might provide plenty of negative charge at high temperature, which can convert the (ANI)n‐b‐PEO‐b‐(ANI)n into n‐type thermoelectric materials. To adjust the number of aniline unit, (ANI)8‐b‐PEO‐b‐(ANI)8 shows excellent n‐type characteristics with Seebeck coefficient as large as −1171 µV K−1 at 381 K. The strong interaction between PEO and aniline oligomers plays a dominant role in the n‐type thermoelectric performance of the triblock copolymers, which have potential application in the field of PTEGs and temperature sensors. [ABSTRACT FROM AUTHOR]

Isoindoline nitroxide-containing porphyrins were synthesized by the reaction of 5-phenyldipyrromethane and 5-(4′-nitrophenyl)-dipyrromethane with 5-formyl-1,1,3,3-tetramethylisoindolin-2-yloxyl using the Lindsey method. These spin-labeled porphyrins were further characterized by MS, UV, FTIR, 1H-NMR, cyclic voltammetry, electron paramagnetic resonance (EPR), and fluorescence spectroscopy. The electrochemical assay demonstrated that these isoindoline nitroxides-containing porphyrins had similar electrochemical and redox properties as 5-carboxy-1,1,3,3-tetramethylisoindolin-2-yloxyl. Electron paramagnetic resonance test exhibited these porphyrins possessed the hyperfine splittings and characteristic spectra of isoindoline nitroxides, with typical nitroxide g-values and nitrogen isotropic hyperfine coupling constants. Fluorescence spectroscopy revealed that these porphyrins indicated fluorescence suppression characteristic of nitroxide-fluorophore systems. Moreover, their reduced isoindoline nitroxide-containing porphyrins eliminated the fluorescence suppression and displayed strong fluorescence. Thus, these isoindoline nitroxide-containing porphyrins may be considered as the potential fluorescent and EPR probes. [ABSTRACT FROM AUTHOR]