fig2

Figure 2. (A) Illustrations of the dendrite-free PM/NiO/K and caducous dendritic Cu/K electrode. This figure is quoted with permission from Li et al.^[66]. (B) The fabrication process of the K-ACM, and schematics of electron and ion channels in a traditional chunk of metallic K and in a K-ACM electrode; electrochemical performance of symmetric cells with bare K or K-ACM electrodes; comparison of the cyclic stability and coulombic efficiency of the K-ACM/PB and K/PB cells at a rate of 0.5 C. This figure is quoted with permission from Qin et al.^[67].