Possibilities and Constraints of the Electrochemical Treatment of Thiophene on Low and High Oxidation Power Electrodes

Abstract

In this research, the electrochemical oxidation of thiophene at platinum and dimensionally stable anode (DSA) electrodes as low oxidation power anodes and at lead/lead oxide (Pb/PbOx) and boron-doped diamond (BDD) electrodes as high oxidation power anodes was comprehensively studied by determining the rate and degree of the electrochemical thiophene oxidation, the Coulombic efficiency (CE), and the selectivity of polar product formation [thiophene-2-one and 3hydroxythiophene-2(3H)-one (Thyox)]. The DSA showed the best performance among the low oxidation power electrodes, with a selectivity of 84.54% toward Thyox formation, a product formation rate of 224.51 mmol/(h m 2 ), a CE of 23.04%, and thiophene conversion of 97.96% in 0.5 M H 2 SO 4 solution for 3 h in ambient temperature. The conversion of thiophene was approximately the same using Pb/PbOx and BDD (about 92%), but Pb/PbOx yielded higher selectivity and product formation rate for Thyox formation [73.68% and 117.72 mmol/(h m 2 ), respectively]. However, CE of BDD (62%) was nearly 3 times greater than that of Pb/PbOx at lower potentials. The experimental results can provide a clear decision in the exploitation of oxidation processes at the industrial scale and could be easily extended to other thiophenic compounds.

Polymerization of Solid-State 2,2′-Bithiophene Thin Film or Doped in Cellulose Paper Using DBD Plasma and Its Applications in Paper-Based Electronics

“…The 2,2′-bithiophene film shows one band at 306 nm in the UV–vis spectrum. When this film was treated with DBD, the 306 nm band decreased and a new band at 398 nm was observed (Figure ), which was attributed to the n−π* electronic transition absorption of the conjugated PBT polymer. ,− During the plasma treatment, the band of the 2,2′-bithiophene monomer at 306 nm gradually decreased, and the peaks of the PBT polymer increased. In the experiment, the same sample was exposed to the plasma again and again.…”

One pot synthesis and characterization of binary and ternary metal organic frameworks (MOFs) as tri-modal catalysts for thiophene electrooxidation, water splitting and 4-nitrophenol reduction

“…26,27 Mechanistic aspects of the electrochemical oxidation of thiophene at platinum and a dimensionally stable anode (DSA) electrode, lead/lead oxide (Pb/PbO x ) and a boron-doped diamond (BDD) electrode had been well studied. 28 Though few studies are available in the literature on the ECDS process using such anodes, these are all direct electrochemical oxidation processes where the decomposition voltages are usually very high in organic and in aqueous electrolytes. Furthermore, the high cost and scarcity of certain metals or metal oxides preclude their widespread commercialization.…”