Amplifying reactivity of bio-inspired [FeFe]-hydrogenase mimics by organic nanotubes.

ABSTRACT

A bio-inspired FeFe hydrogenase model which catalyses hydrogen evolution reaction (HER) in acidic solutions is immobilized in polyaniline (PANI)-based nanotubes. A combination of analytical techniques reveals that this construct maintains both the molecular signatures of the bio-inspired complex and the material properties of PANI. The amine and imine-rich environment of the PANI chain amplifies the inherent HER activity of the bio-inspired complex, allowing electrocatalytic HER at neutral pH, with lower overpotentials and higher current densities compared to the bio-inspired complex alone. This construct retains the oxygen stability of the bio-inspired complex and remains stable through several hours of aerobic electrolysis, producing only 6.5% H2O2 from the competing oxygen reduction reaction (ORR).