Conductive One-Dimensional Coordination Polymers with Tunable Selectivity for the Oxygen Reduction Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Nonprecious metal coordination complexes are gaining traction as electrocatalysts for the oxygen reduction reaction (ORR).
• Developing efficient and selective ORR electrocatalysts is crucial for energy conversion technologies.

Purpose of the Study:

• To report efficient ORR electrocatalysts based on one-dimensional (1D) coordination polymers (CPs) with tunable selectivity.
• To explore the potential of M-S2N2 sites within conductive CPs for ORR applications.

Main Methods:

• Synthesized 1D CPs from M(OAc)2 and 2,5-diamino-1,4-benzenedithiol (DABDT) using a solvent thermal method.
• Investigated the electrical conductivity and electrocatalytic activity of the synthesized CPs for ORR in alkaline media.

Main Results:

• The 1D CPs exhibited good electrical conductivities (10^-6–10^-2 S cm^-1), enabling their use as ORR catalysts without carbon additives.
• Cobalt-based CPs displayed nanosheet structures with exposed Co-S2N2 sites, demonstrating remarkable ORR activity (E_onset = 0.93 V, E_1/2 = 0.82 V).
• Nickel-based CPs facilitated a 2e- ORR pathway, achieving approximately 87% H2O2 selectivity with an E_onset of 0.78 V.

Conclusions:

• Conductive nonprecious metal CPs with M-S2N2 sites offer a promising platform for designing tunable ORR electrocatalysts.
• The study highlights the potential of these materials for efficient oxygen reduction and selective hydrogen peroxide production.