Rational design of heterogenized molecular phthalocyanine hybrid single-atom electrocatalyst towards two-electron oxygen reduction

• Published in: Nature communications 2023-03, Vol.14 (1), p.1426-1426, Article 1426
• Main Authors: Fan, Wenjun, Duan, Zhiyao, Liu, Wei, Mehmood, Rashid, Qu, Jiating, Cao, Yucheng, Guo, Xiangyang, Zhong, Jun, Zhang, Fuxiang
• Format: Article
• Language: English
• Subjects: 140/146; 147/143; 639/301/299/161/886; 639/301/299/886; 639/638/161/886; 639/638/77/886; Carbon nanotubes; Catalysts; Chemical reduction; Cobalt; Coordination; Density functional theory; Efficiency; Electrocatalysts; Humanities and Social Sciences; Hydrogen peroxide; Metal phthalocyanines; multidisciplinary; Nanotechnology; Nanotubes; Oxygen; Oxygen reduction reactions; Reaction mechanisms; Science; Science (multidisciplinary); Screening; Selectivity; Single atom catalysts; Substrates
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-023-37066-y

Single-atom catalysts supported on solid substrates have inspired extensive interest, but the rational design of high-efficiency single-atom catalysts is still plagued by ambiguous structure determination of active sites and its local support effect. Here, we report hybrid single-atom catalysts by an axial coordination linkage of molecular cobalt phthalocyanine with carbon nanotubes for selective oxygen reduction reaction by screening from a series of metal phthalocyanines via preferential density-functional theory calculations. Different from conventional heterogeneous single-atom catalysts, the hybrid single-atom catalysts are proven to facilitate rational screening of target catalysts as well as understanding of its underlying oxygen reduction reaction mechanism due to its well-defined active site structure and clear coordination linkage in the hybrid single-atom catalysts. Consequently, the optimized Co hybrid single-atom catalysts exhibit improved 2e − oxygen reduction reaction performance compared to the corresponding homogeneous molecular catalyst in terms of activity and selectivity. When prepared as an air cathode in an air-breathing flow cell device, the optimized hybrid catalysts enable the oxygen reduction reaction at 300 mA cm −2 exhibiting a stable Faradaic efficiency exceeding 90% for 25 h. Difficulties in elucidating active sites and the role of the support hamper the development of high-efficiency two-electron oxygen reduction electrocatalysts. Here, the authors develop hybrid single-atom catalysts by rational experimental and theoretical screening for hydrogen peroxide production.