Dan Meng, Zhang Xiting, Yang Yongchao, Yang Jingfei, Wu Fengxiu, Zhao Shenlong, Liu Zhao-Qing
School of Chemistry and Chemical Engineering/Institute of Clean Energy Materials/Guangzhou Key Laboratory for Clean Energy and Materials/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, People's Republic of China.
College of Materials Science & Engineering, Taiyuan University of Technology, Shanxi 030024, People's Republic of China.
Proc Natl Acad Sci U S A. 2024 Feb 6;121(6):e2318174121. doi: 10.1073/pnas.2318174121. Epub 2024 Jan 30.
Atomically dispersed catalysts are a promising alternative to platinum group metal catalysts for catalyzing the oxygen reduction reaction (ORR), while limited durability during the electrocatalytic process severely restricts their practical application. Here, we report an atomically dispersed Co-doped carbon-nitrogen bilayer catalyst with unique dual-axial Co-C bonds (denoted as Co/DACN) by a smart phenyl-carbon-induced strategy, realizing highly efficient electrocatalytic ORR in both alkaline and acidic media. The corresponding half-wave potential for ORR is up to 0.85 and 0.77 V (vs. reversible hydrogen electrode (RHE)) in 0.5 M HSO and 0.1 M KOH, respectively, representing the best ORR activity among all non-noble metal catalysts reported to date. Impressively, the Zn-air battery (ZAB) equipped with Co/DACN cathode achieves outstanding durability after 1,688 h operation at 10 mA cm with a high current density (154.2 mA cm) and a peak power density (210.1 mW cm). Density functional theory calculations reveal that the unique dual-axial cross-linking Co-C bonds of Co/DACN significantly enhance the stability during ORR and also facilitate the 4e ORR pathway by forming a joint electron pool due to the improved interlayer electron mobility. We believe that axial engineering opens a broad avenue to develop high-performance heterogeneous electrocatalysts for advanced energy conversion and storage.
原子分散催化剂是催化氧还原反应(ORR)的铂族金属催化剂的一种有前景的替代物,然而电催化过程中有限的耐久性严重限制了它们的实际应用。在此,我们通过一种巧妙的苯基碳诱导策略报道了一种具有独特双轴Co-C键的原子分散的钴掺杂碳氮双层催化剂(记为Co/DACN),在碱性和酸性介质中均实现了高效的电催化ORR。在0.5 M HSO和0.1 M KOH中,ORR的相应半波电位分别高达0.85和0.77 V(相对于可逆氢电极(RHE)),代表了迄今为止报道的所有非贵金属催化剂中最佳的ORR活性。令人印象深刻的是,配备Co/DACN阴极的锌空气电池(ZAB)在10 mA cm下运行1688小时后,具有高电流密度(154.2 mA cm)和峰值功率密度(210.1 mW cm),展现出出色的耐久性。密度泛函理论计算表明,Co/DACN独特的双轴交联Co-C键显著提高了ORR过程中的稳定性,并且由于层间电子迁移率的提高形成了联合电子池,也促进了4e ORR途径。我们相信,轴向工程为开发用于先进能量转换和存储的高性能非均相电催化剂开辟了一条广阔的道路。