Metal-free carbon materials have emerged as cost-effective and high-performance catalysts for the production of hydrogen peroxide (H2O2) through the two-electron oxygen reduction reaction (ORR). Here, we show that 3D crumpled...

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202109767. 10 mAh cm -2 in Na//Cu asymmetric cells, as well as over 14 400 cycles at 60 mA cm -2 in Na//Na symmetric cells. Density functional theory calculations reveal that the superior cycling performance of PC-CFe stems from the stronger adsorption of Na on the surface of the CFe, providing initial nucleation sites more favorable to Na deposition. Moreover, the full cell with a PC-CFe host without Na metal and a high-loading Na 3 V 2 (PO 4 ) 3 cathode (10 mg cm -2 ) maintains a high capacity of 103 mAh g -1 at 1 mA cm -2 even after 100 cycles, demonstrating the operation of anode-free SMBs.

The significant performance decay in conventional graphite anodes under low-temperature conditions is attributed to the slow diffusion of alkali metal ions, requiring new strategies to enhance the charge storage kinetics at low temperatures. Here, nitrogen (N)-doped defective crumpled graphene (NCG) is employed as a promising anode to enable stable low-temperature operation of alkali metal-ion storage by exploiting the surface-controlled charge storage mechanisms. At a low temperature of −40 °C, the NCG anodes maintain high capacities of ≈172 mAh g −1 for lithium (Li)-ion, ≈107 mAh g −1 for sodium (Na)ion, and ≈118 mAh g −1 for potassium (K)-ion at 0.01 A g −1 with outstanding rate-capability and cycling stability. A combination of density functional theory (DFT) and electrochemical analysis further reveals the role of the N-functional groups and defect sites in improving the utilization of the surface-controlled charge storage mechanisms. In addition, the full cell with the NCG anode and a LiFePO 4 cathode shows a high capacity of ≈73 mAh g −1 at 0.5 °C even at −40 °C. The results highlight the importance of utilizing the surface-controlled charge storage mechanisms with controlled defect structures and functional groups on the carbon surface to improve the charge storage performance of alkali metal-ion under low-temperature conditions.

The surging demand for environmental‐friendly and safe electrochemical energy storage systems has driven the development of aqueous zinc (Zn)‐ion batteries (ZIBs). However, metallic Zn anodes suffer from severe dendrite growth and large volume change, resulting in a limited lifetime for aqueous ZIB applications. Here, it is shown that 3D mesoporous carbon (MC) with controlled carbon and defect configurations can function as a highly reversible and dendrite‐free Zn host, enabling the stable operation of aqueous ZIBs. The MC host has a structure‐controlled architecture that contains optimal sp2‐carbon and defect sites, which results in an improved initial nucleation energy barrier and promotes uniform Zn deposition. As a consequence, the MC host shows outstanding Zn plating/stripping performance over 1000 cycles at 2 mA cm−2 and over 250 cycles at 6 mA cm−2 in asymmetric cells. Density functional theory calculations further reveal the role of the defective sp2‐carbon surface in Zn adsorption energy. Moreover, a full cell based on Zn@MC900 anode and V2O5 cathode exhibits remarkable rate performance and cycling stability over 3500 cycles. These results establish a structure‐mechanism‐performance relationship of the carbon host as a highly reversible Zn anode for the reliable operation of ZIBs.

As lithium (Li)‐ion batteries expand their applications, operating over a wide temperature range becomes increasingly important. However, the low‐temperature performance of conventional graphite anodes is severely hampered by the poor diffusion kinetics of Li ions (Li+). Here, zinc oxide (ZnO) nanoparticles are incorporated into the expanded graphite to improve Li+ diffusion kinetics, resulting in a significant improvement in low‐temperature performance. The ZnO–embedded expanded graphite anodes are investigated with different amounts of ZnO to establish the structure‐charge storage mechanism‐performance relationship with a focus on low‐temperature applications. Electrochemical analysis reveals that the ZnO–embedded expanded graphite anode with nano‐sized ZnO maintains a large portion of the diffusion‐controlled charge storage mechanism at an ultra‐low temperature of −50 °C. Due to this significantly enhanced Li+ diffusion rate, a full cell with the ZnO–embedded expanded graphite anode and a LiNi0.88Co0.09Al0.03O2 cathode delivers high capacities of 176 mAh g−1 at 20 °C and 86 mAh g−1 at −50 °C at a high rate of 1 C. The outstanding low‐temperature performance of the composite anode by improving the Li+ diffusion kinetics provides important scientific insights into the fundamental design principles of anodes for low‐temperature Li‐ion battery operation.