Design, synthesis, fabrication and simulation of conjugated molecule for detection of lithium ions

Alkali metal ions such as lithium, sodium and potassium are essential chemical species present in biological fluids (0.5-1.2 mM) and less hazardous quantity (0.9 mu M-12 mu M) present in drinking water. Lithium salts are used in pharmaceuticals, in ores and minerals, in Li-ion batteries. Ingestion of water source containing lithium concentration above 0.2 mM affects normal functioning of the body. Hence it is important to detect these ions in potable water. Here, a conjugated molecule based sensor for detection of lithium ion in water is developed. The conjugated molecule has a receptor moiety to capture the ion. The conjugated molecule interaction with alkali metal ions - Li+,Na+ and K+ is studied by density functional theory and interference analysis. The resistive based sensor is fabricated and device characteristics are studied. The experimental and simulation results suggest that the conjugated molecule interaction specifically with Li+ is relatively stronger. The lower limit of detection of the sensor is observed to be 0.05 mM. This limit is within the range of the lithium ion concentration found in biological fluids

Programmable dual electrochromism in azine linked conjugated polymer

A conjugated polymer consisting of tri-EDOT and azine groups was synthesized and explored for a programmable dual electrochromic device. Electrochemical doping (oxidation) and de-doping (reduction) resulted in the two distinct redox pairs, depending on the applied potential range. In situ spectroelectrochemical analyses revealed that the stepwise redox process of two units was associated with dual electrochromic responses: tri-EDOT unit for purple electrochromism followed by azine unit for blue electrochromism. Dual electrochromism of purple and blue was attainable at below 1.0 V which could induce the color transition upon the potential application of around ± 1 V. Maximum coloration efficiency of 393 cm2/C with a response time of 1 s was obtained.1121sciescopu

Novel Thiophene–Phenylene–Thiophene Fused Bislactam-Based Donor–Acceptor Type Conjugate Polymers: Synthesis by Direct Arylation and Properties

Three new donor–acceptor copolymers based on thiophene–phenylene–thiophene fused bislactam and various donors (3,4-dodecylthiophene, 4,4′-didodecyl-2,2′-bithiophene, and ethylenedioxythiophene) were synthesized, characterized, and used in field-effect transistors. Polycondensation was performed using nonactivated thiophene derivatives by employing palladium-catalyzed direct arylation under phosphine-free conditions. This method is superior to traditional cross-coupling polymerization because it requires fewer synthetic operations and does not employ toxic organometallic intermediates. Regioselective polymers can also be generated by using β-substituted thiophene derivatives. The studied polymers were tested in a bottom gate top contact thin film transistor (OTFT) architecture. The best electronic performance was shown by polymer <b>P3</b>, with enhanced π-conjugation due to the appearance of intramolecular attractive interactions