Ambient stable perylene diimide anion radical for high conductivity and potential application as chemiresistive sensor

Purpose This paper aims to compare the electronic properties of perylene diimide derivatives (DFPDI) and its anion radical (DFPDI.-k.+) thin film by drop-coating of organic molecules on the interdigitated electrodes. Design/methodology/approach The authors compared the electronic properties of perylene diimide derivatives and its anion radical by drop-coating of organic molecules on interdigitated electrodes. Significantly, the current of perylene diimide derivatives anion radical increased by 2∼3 orders of magnitude compared to perylene diimide derivatives under a bias of 5 V, and the maximal current of anion radical that from tetrahydrofuran solution can reach 3.6 mA. Furthermore, DFPDI.-k.+ thin film showed time-resistance sensitivity for acetic acid. When DFPDI.-k.+ thin film was placed in acetic acid of 3.1 × 105 ppm, the current was decreased 46 times under a bias of 6 V after 8 min. Findings We developed the new method to prepare ambient stable perylene diimide derivatives anion radical, which shows sensitivity of absorption spectra to acid. Originality/value Perylene diimide derivatives anion radical thin film showed time-resistance sensitivity for acetic acid, suggesting potential application of perylene diimide derivatives anion radical as acid sensor.

Synthesis and properties of bay unilaterally extended and mono-substituted perylene diimides

The synthesis of two sulfur-decorated perylene diimides, the five-membered S-heterocyclic annulated perylene diimide (1) and 1-propanethiol- N,N′-dicyclohexylperylene-3,4,9,10-tetracarboxylic diimide (2), and a novel sulfoxide-containing perylene diimide, 1-propyl sulfoxide- N,N′-dicyclohexylperylene-3,4,9,10-tetracarboxylic diimide (3), are reported. The photophysical, electrochemical, aggregation, and thermal properties of these compounds are investigated by ultraviolet visible absorption, fluorescence, cyclic voltammetric, X-ray diffraction, and thermogravimetric analysis techniques. The geometries of the compounds are optimized at the 6-31G* level of theory using density functional theory, and their potentials are correlated with molecular orbitals. The prepared perylene diimide derivatives exhibit narrow the highest occupied molecular orbitals and the lowest unoccupied molecular orbitals band gaps, and they have quite different absorptions and emissions in dichloromethane solutions, which are in agreement with the density functional theory–calculated results.