Constructing the active interface in a heterojunction electrocatalyst is critical for the electron transfer and intermediate adsorption (O*, OH*, and HOO*) in alkaline oxygen evolution reaction (OER) but still remains challenging. Herein, a CeO 2 / Co 4 N heterostructure is rationally synthesized through the direct calcination of Ce[Co(CN) 6 ], followed by thermal nitridation. The in situ electrochemically generated CoOOH on the surface of Co 4 N serves as the active site for the OER, and the coupled CeO 2 with oxygen vacancy can optimize the energy barrier of intermediate reactions of the OER, which simultaneously boosts the OER performance. Besides, electrochemical measurement results demonstrate that oxygen vacancies in CeO 2 and optimized absorption free energy originating from the electron transfer between CeO 2 and CoOOH contribute to enhanced OER kinetics. This work provides new insight into regulating the interface heterostructure to rationally design efficient OER electrocatalysts under alkaline conditions.

Room‐temperature sodium‐sulfur (RT Na–S) batteries are regarded as one of promising next‐generation energy storage systems owing to the high theoretical energy density (1274 Wh kg−1) and rich abundance of the raw materials. However, the sluggish redox kinetics and low electrical conductivity of sulfur (S) cathode significantly imped their practical application. Herein, a flexible carbon film implanted with single‐atomic Zn−N2 moiety (Zn‐N2/CF) is constructed as the efficient S host material to effectively improve the redox kinetics and electrical conductivity. The theoretical and experimental results show that, compared to Zn−N4 center, unsaturated Zn−N2 center with asymmetric electron distribution has significant advantages in anchoring and activating sodium polysulfides to accelerate the conversion from S8 to Na2S and reducing the reaction energy barrier of Na2S decomposition. Consequently, Zn‐N2/CF/S can retain a reversible capacity of 838.5 mAh g−1 at 0.1 A g−1 after 100 cycles, which is higher than that of Zn‐N4/CF/S (688.0 mAh g−1). Moreover, Zn‐N2/CF/S also maintains a long‐term cycling performance with a negligible capacity decay rate of 0.006% per cycle over 4000 cycles at 10 A g−1. This work provides an effective strategy to obtain the flexible carbon film implanted with unsaturated single‐atomic structure, thereby ultimately resulting in high‐performance RT Na–S batteries.

Herein, we make use of the large-sized Se atom to regulate the local structure of the graphitic lattice to optimize N-doping species to strengthen the adsorption of K+, which can greatly boost the capacitive capacity for PIBs.