Electropolymerization of 3',4'-disubstituted 2,2':5',2″-terthiophene derivatives. A theoretical and photovoltaic characterization.

In the present work a series of β-substituted thiophenes have been synthesized and their electrochemical behavior studied. The products obtained by electro-oxidation are highly dependent on the substituent, affording sometimes conducting polymers, insulating layers or soluble species. This behavior has been ascribed to specific electronic and/or steric factors.

Determination of mercury in hair by square-wave anodic stripping voltammetry at a rotating gold disk electrode after microwave digestion.

A simple and reliable method for the determination of mercury in hair on a rotating gold disk electrode using subtractive anodic stripping voltammetry without removal of oxygen is reported. Voltammetric and microwave parameters were optimized to obtain the best analytical results. Parameters such as supporting electrolyte concentration, influence of chloride in the Hg peak, deposition potential, scan rate, accumulation time, rotation rate, square-wave amplitude, and electrode conditioning were studied.