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We have designed a flexible electrochemical transducer film based on PEDOT–titania–poly(dimethylsiloxane) (PTS) for the simultaneous detection of neurotransmitters. PTS films were characterized using various techniques such as transmission electron microscopy, scanning electron microscopy, atomic force microscopy, four probe electrical conductivity, ac-impedance, and thermomechanical stability. The electrocatalytic behavior of the flexible PTS film toward the oxidation of neurotransmitters was investigated using cyclic voltammetry and differential pulse voltammetry. The fabricated transducer measured a limit of detection of 100 nm ± 5 with a response time of 15 s and a sensitivity of 63 μA mM–1 cm–2. The fabricated transducer film demonstrated for the simultaneous determination of epinephrine, dopamine, ascorbic acid, and uric acid with no interference between the analyte molecules. Further, transducer performance is validated by performing with real samples. The results suggested that the fabricated flexible PTS transducer with superior electrocatalytic activity, stability, and low response time can be explored for the sensing of neurotransmitters and hence can be exploited at in vitro and in vivo conditions for the early detection of the various diseases.

We have demonstrated patterning of highly ordered nanostructured conducting PEDOT (poly(3,4-ethylenedioxythiophene)) on glassy carbon electrode (GCE) through electrochemical polymerization of a biobased liquid crystalline template of EDOT-PDPPA (3-pentadecylphenyl phosphoric acid). Self-assembled "EDOT-PDPPA" in water exhibited lyotropic liquid crystalline (LC) phases of nematic gyroid, columnar, and lamellar phases. Studies revealed that, during electrochemical polymerization, PEDOT-PDPPA mimicked the anisotropic domains of its monomer LC template. Nyquist plot showed enhancement in conductivity with a positive change in the HOMO- LUMO gap. Further, the efficiency of the modified GCE was demonstrated as an electrochemical transducer for the detection of nicotine. It was observed that oxidation of nicotine occurs at lower potential (0.83 V) with higher current (54.63 μA) compared to bare GCE (1.1 V, 17.86 μA) with nanomolar detection. This simple strategy of electrochemical patterning of conductive polymer on a conventional electrode can be exploited for the high tech applications in miniaturized plastronic devices.

Nitrogen-containing porous carbon derived from sucrose and thiourea by an environmentally friendly and economically feasible technique has been explored as a negative electrode for sodium-ion batteries (SIBs). Aforesaid sucrose−thiourea-derived carbon (STU) contains micro-, meso-, and macroporous particles with a significant surface area of 2070 m 2 /g. When examined as an negative electrode in SIB applications, STU delivers an appreciable electrochemical performance upon moderate-rate (50 mA/g) and high-rate (1.6 A/g) charge conditions. A steady-state progressive capacity of 285 mAh/g is observed at 50 mA/g after 100 cycles. Further, an STU negative electrode delivers an appreciable capacity of 216 mAh/g after 600 cycles with 77% capacity retention. Furthermore, a high reversible capacity of 132 mAh/g was obtained at 1.6 A/g after 230 cycles. The excellent electrochemical activity of an STU negative electrode for SIB application is believed to be due to the presence of a combination of micro-, meso-, and macropores along with a high surface area and more edges and defect sites of carbon.

This article demonstrates the design and fabrication of an electrochemical sensor based on a platinum electrode for ascorbic acid (AA) modified by an electromagnetic polyaniline–Keggin iron–clay (PPICS) composite. The polyaniline–polyhydroxy iron–clay composite was prepared by the polymerization of [Anilinium]+[PDPSA]− in the presence of Keggin iron intercalated clay and was characterized for its particle size, morphology, electrical conductivity, and saturation magnetization. The oxidation potential of AA was observed at +0.4 V on the bare electrode and shifted to a negative potential of −0.32 V on the modified electrode. Common possible interferences of the sample matrices were tested, and the results reveal that the PPICS‐modified electrode exhibited a high selectivity and sensitivity toward AA. This unique low‐cost and user‐friendly sensor was validated for the nanomolar detection of AA present in real samples. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40936.

Energy storage devices accomplished with efficient LAPONITE® liquid crystalline gel electrolytes.