Electrochemical conversion of acrylonitrile (AN) to produce
adiponitrile
(ADN), the raw material for the production of Nylon 66, has become
a crucial process owing to the increasing market demand of Nylon 66.
Although the metallic Pb or Cd electrodes are commonly used for this
reaction, the use of electrocatalysts or electrodes modified with
catalysts has been barely investigated. In this study, nanoporous
and electrically conductive metal–organic framework (MOF)-derived
materials composed of Pb, PbO, and carbon are synthesized by carbonizing
a Pb-based MOF through thermal treatments, and these MOF-derived materials
are served as electrocatalysts for the electrosynthesis of ADN. The
crystallinity, morphology, elemental composition, porosity, electrical
conductivity, and electrochemically active surface area of each MOF-derived
material are investigated. Mass-transport-corrected Tafel analysis
is used to probe the enhanced kinetics for the electrochemical reduction
of AN occurring at the electrode modified with the MOF-derived material.
Electrolytic experiments at various applied potentials are conducted
to quantify the production rate and Faradaic efficiency toward ADN,
and the result shows that the MOF-derived materials can act as electrocatalysts
to initiate the electrochemical reduction of AN to produce ADN at
a reduced overpotential. The optimal MOF-derived electrocatalyst can
achieve a Faradaic efficiency of 67% toward ADN at an applied potential
of −0.85 V versus reversible hydrogen electrodea much
lower overpotential compared to that typically required for this reaction
without the use of catalysts. Findings here shed light on the design
and development of advanced electrocatalysts to boost the performances
for the electrosynthesis of ADN.