Self-Assembled Covalent Triazine Frameworks Derived N, S Co-Doped Carbon Nanoholes with Facilitating Ions Transportation Toward Remarkably Enhanced Oxygen Reduction Reaction and for Zinc-Air Batteries.

Abstract

Listen

Translate article

3D assembled carbon materials, featuring unique hierarchical porosity and interconnected channels, are essential for the advancement of emerging zinc-air batteries (ZABs). In this study, nitrogen (N) and sulfur (S) co-doped 3D carbon nanoholes (N/S-CNHs) are synthesized through a straightforward procedure involving self-assembly followed by carbonization. This process utilizes a hybrid of self-assembled covalent triazine framework and sodium lignosulphonate (CTF@LS) as a multifunctional precursor. The resulting N/S-CNHs exhibit a distinctive nanoholes microstructure composed of interwoven carbon nanoclusters, which facilitates efficient ion and electron transport during the electrocatalytic process. The incorporation of N and S atoms intriguingly alters the wetting properties of the catalyst microenvironment, thereby significantly facilitating the transfer of key intermediates and their interaction with the electrolyte. Consequently, the optimized N/S-CNH-900 demonstrates remarkable electrocatalytic activity for the ORR (E1/2 = 0.86V vs RHE), surpassing the performance of state-of-the-art Pt/C electrocatalyst. Theoretical calculations reveal that the synergistic effect of N and S heteroatom doping significantly enhances *OOH desorption and its transformation to O*, thereby markedly accelerating the ORR process. Furthermore, both liquid and quasi-solid ZABs equipped with the N/S-CNH-900 cathode exhibit improved peak power density and specific capacity relative to those employing commercial Pt/C catalysts.