Rationally designed nitrogen-doped carbon macroporous fibers with loading of single cobalt sites for efficient aqueous Zn-CO2 batteries

Atomically dispersed metal catalysts supported on the rigidly hollow matrix are promising materials for developing carbon-neutral technologies. Herein, we develop an elaborate multistep templating approach to fabricate cobalt single-atom-decorated nitrogendoped carbon macroporous fibers (Co SAs@NCMFs). During the thermal reduction, the cobalt nanoparticles derived from the sintered Co2+ ions are formed at 600 degrees C, which can be further transformed into unevenly loaded atomically dispersed cobalt sites at 1,000 degrees C. The Co SAs@NCMF catalyst delivers excellent CO Faradaic efficiency (98.4%) and turnover frequency (38,390 h(-1)) at -1.0 V versus reversible hydrogen electrode for CO2 electroreduction. Furthermore, benefiting from the multiple advantageous features, including rigidly hollow structure, high specific surface area, and accessible active sites, the Co SAs@NCMF electrode shows outstanding rechargeability and stable cycle life in aqueous ZnCO2 batteries.

Automated summary

Atomically dispersed metal catalysts are promising materials for carbon-neutral technologies. Researchers developed a multistep templating approach to fabricate cobalt single-atom-decorated nitrogen-doped carbon macroporous fibers, which exhibited excellent performance in CO2 electroreduction and aqueous ZnCO2 batteries.