Cofunction of Protons as Dopant and Reactant Activate the Electrocatalytic Hydrogen Evolution in Emeraldine-Polyguanine

Abstract

Functional conductive polymers represent an emerging class of nonmetallic electrocatalysts attractive to substitute scarce and expensive elements used today. Here the synthesis of emeraldine-polyguanine as structural-molecular analog to polyaniline is shown and the conducting biopolymer as molecular hydrogen electrocatalyst is applied. The polymerized and protonated nucleobase aids the catalytic electroreduction of protons over a peculiar mechanism, where, over amino-association, protons coserve as dopant and reactant. In acidic media the electrocatalytic evolution of hydrogen at a Tafel slope of 79 mV dec−1 at 290 mV overpotential (10 mA cm−2) is reported. The 140h initial stability test demonstrates that the functionality of polymerized nucleobases can be harnessed for heterogeneous catalysis, i.e., as here demonstrated for the electroconversion of hydrogen.