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Yolk–shell structured micro/nano‐sized materials have broad and important applications in different areas due to their unique spatial configurations. In this study, yolk–shell structured Co3O4@Co3O4 is prepared using a simple and scalable hydrothermal reaction, followed by a calcination process. Then, CoxCu1−xCo2O4@CoyCu1−yCo2O4 microspheres are synthesized via adsorption and calcination processes using the as‐prepared Co3O4@Co3O4 as the precursor. A possible formation mechanism of the yolk–shell structures is proposed based on the characterization results, which is different from those of yolk–shell structures in previous study. For the first time, the catalytic activity of yolk–shell structured catalysts in ammonia borane (AB) hydrolysis is studied. It is discovered that the yolk–shell structured CoxCu1−xCo2O4@CoyCu1−yCo2O4 microspheres exhibit high performance with a turnover frequency (TOF) of 81.8 molhydrogen min−1 molcat−1. This is one of the highest TOF values reported for a noble‐metal‐free catalyst in the literature. Additionally, the yolk–shell structured CoxCu1−xCo2O4@CoyCu1−yCo2O4 microspheres are highly stable and reusable. These yolk–shell structured CoxCu1−xCo2O4@CoyCu1−yCo2O4 microsphere is a promising catalyst candidate in AB hydrolysis considering the excellent catalytic behavior and low cost.

The rational synthesis of transition metal sulfides with long cycle life and good rate performance is essential for building superior electrochemical energy storage devices. In this work, the MnS nanoparticles/ N,S-codoping carbon nanotubes (MnS@N,S-C NTs) with double-layer carbon have been synthesized through a facile in situ transformation method. The synergetic coupling effects benefited from the advantages of double N,S-C layers, and porous structures are effective to allow fast electrons/lithium ions transport and keep good structural integrity during the charging/discharging process. Owing to the large surface area, the MnS@N,S-C NTs electrode is mainly pseudocapacitive in nature during the charge−discharge process, which is beneficial to enhance the electrochemical transfer kinetics. When used as anodes for lithium ion batteries, the MnS@N,S-C NTs exhibit a high specific capacity of 796 mAh g −1 during the 200th cycle at 1.0 A g −1 . Even at 10.0 A g −1 , the discharge specific capacity of the MnS@N,S-C NTs can still reach about 400 mAh g −1 during the 9000th cycle with superior rate capability. The proposed approach may promote rational creation of other hybrid functional materials for energy storage and conversion.